Re: [EXT] Re: [External] Re: Step-like basline

[Frank Girgsdies]

Dear Shay,

Dear Rietvelders,

I agree with all who attributed this step to the metal filter (Ni for Cu 
radiation) absorption edge jump.
In our lab, we got rid of this feature recently, when we migrated from 
an older Bruker D8 Advance Series II with LynxEye detector 
(Bragg-Brentano setup with Ni filter) to a D8 Advance A25 with LynxEye 
XE-T. Operating the XE-T in high energy resolution mode discriminates K 
beta electronically, making the Ni filter obsolete and thus removing the 
edge jump.


However, I have to disagree with Matthew about TOPAS modeling this edge 
jump "quite well".
(Disclaimer: I'm not running the latest version of TOPAS, and I'm 
probably not up to date with the custom macros that are available in the 
community. Thus, my statement might be outdated!)

I am using DIFFRAC.SUITE TOPAS version 5.
Firstly, this version of the macro contains a bug, which is described in 
the supporting information of Lipp et al. 
(https://doi.org/10.1021/acs.chemmater.2c00101). In a nutshell, the 
parameter "cedge_scale", which is not declared anywhere, should actually 
read "cedge_extra".
Secondly, it seems that the macro does not convolute the edge jump 
feature with the sample related peak broadening. Empirically, the 
absorption edge, like any other emission spectrum feature, is only 
clearly visible if the peak is sharp enough. If you happen to have a 
pattern which is composed of both very sharp and very broad peaks, and 
optimize the edge jump macro parameters to model the jump left of the 
sharp peaks, then also the broad peaks will have a sharp jump on top, 
which should not be. I noticed this inconsistency because I usually 
model the broad bump which is often caused by amorphous or 
nano-crystalline material with a broad peak in a Peaks Phase. The 
crystalline phase had sharp peaks with adsorption edge features, so I 
tried to model this using the macro. While the bases of the sharp peaks 
were now modeled nicely, the broad amorphous bump had an annoying sharp 
edge jump on top.
To conclude, TOPAS with its versatile macro language certainly has the 
potential to model this feature correctly, but the version of the macro 
that I am aware of needs to be improved...


With best wishes,
Frank

--
Frank Girgsdies
Fritz-Haber-Institut der Max-Planck Gesellschaft
Department of Inorganic Chemistry / CatLab


On 04.09.2023 00:50, Matthew Rowles wrote:
Topas can model them quite well. The functionality was introduced in 
version 5.


On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber, > wrote:


Hi,  Are these things modeled in Rietveld programs, by chance?  It
seems like a lot of baggage to put in a refinement but if it makes
the results better…

__ __

  * Kurt

__ __

*From:* rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@ill.fr>> *On
Behalf Of *Thomas Gegan
*Sent:* Sunday, September 3, 2023 9:16 AM
*To:* Bish, David L mailto:b...@indiana.edu>>;
Shay Tirosh mailto:stiro...@gmail.com>>;
Fernando Igoa mailto:fer.igoa.1...@gmail.com>>
*Cc:* Rietveld List (rietveld_l@ill.fr )
mailto:rietveld_l@ill.fr>>
*Subject:* RE: [EXT] Re: [External] Re: Step-like basline

__ __

I agree with a Ni absorption edge, possibly with a Kβ peak around
38° 2θ.

__ __

*Tom Gegan*
Chemist III

__ __

Phone: +1 732 205-5111, Email: tom.ge...@basf.com

Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike,
08830 Iselin, United States



__ __

*From:* rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@ill.fr>> *On
Behalf Of *Bish, David L
*Sent:* Sunday, September 3, 2023 7:08 AM
*To:* Shay Tirosh mailto:stiro...@gmail.com>>;
Fernando Igoa mailto:fer.igoa.1...@gmail.com>>
*Cc:* Rietveld List (rietveld_l@ill.fr )
mailto:rietveld_l@ill.fr>>
*Subject:* [EXT] Re: [External] Re: Step-like basline

__ __



Some people who received this message don't often get email from
b...@indiana.edu . Learn why this is
important





Hello Shay,

I think it is probably related to "tube tails". You can read about
this in the literature (e.g., on the BGMN web site) and you can
model it in some Rietveld software such as Topas. You don't normally
notice this but it becomes apparent with higher-intensity peaks.

__ __

Regards,

Dave



*From:*rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@il

Re: [EXT] Re: [External] Re: Step-like basline

[Alan W Hewat]

Reinhard is right that it is best to improve the instrument to produce
cleaner data. I'm concerned about the advice to model all kinds of features
whose origin is not fully understood, simply to obtain a better fit. Shay
has told us nothing about his instrument or his conditions of data
collection. He asks "Is it a sample preparation problem", to which
the obvious reply is "Do you see this with other samples or different
materials" ? Only he can answer that. If the answer is yes, he might try
modifying his instrument (remove filters etc) to see what effect that has
on the pattern from a simple well characterised material. Again only he can
do that. Data collection is an experimental science, and data refinement
should not be reduced to a "black box" computer program where extra
parameters can be added to reduce the R-factor.
Alan.

On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg <
kleeb...@mineral.tu-freiberg.de> wrote:

> Can be modeled in the BGMN peak profile model as well, by modifying
> the *.lam file by a series of additional Lorentzians on the 1/lambda
> scale, see figure.
> The same can be done for other spectral impurities, e.g. W L
> satellites. Also "electronic effects" on the wavelength distribution
> profile like the "edges" from the ROI settings of Si drift detectors
> can be modelled in such a convolution based approach.
> However, better to have a pure/simple wavelength distribution (clear
> alpha1/2 doublet) by a monochromator or high energy resolution
> detector, as any satellites make trouble in trace phase analysis and
> do cause prolonged calculation time in complicated Rietveld refinements.
>
> Reinhard
>
>
>
> Zitat von Matthew Rowles :
>
> > Topas can model them quite well. The functionality was introduced in
> > version 5.
> >
> > On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:
> >
> >> Hi,  Are these things modeled in Rietveld programs, by chance?  It seems
> >> like a lot of baggage to put in a refinement but if it makes the results
> >> better…
> >>
> >>
> >>
> >>- Kurt
> >>
> >>
> >>
> >> *From:* rietveld_l-requ...@ill.fr  *On
> Behalf
> >> Of *Thomas Gegan
> >> *Sent:* Sunday, September 3, 2023 9:16 AM
> >> *To:* Bish, David L ; Shay Tirosh  >;
> >> Fernando Igoa 
> >> *Cc:* Rietveld List (rietveld_l@ill.fr) 
> >> *Subject:* RE: [EXT] Re: [External] Re: Step-like basline
> >>
> >>
> >>
> >> I agree with a Ni absorption edge, possibly with a Kβ peak around 38°
> 2θ.
> >>
> >>
> >>
> >> *Tom Gegan*
> >> Chemist III
> >>
> >>
> >>
> >> Phone: +1 732 205-5111, Email: tom.ge...@basf.com
> >> Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830
> >> Iselin, United States
> >>
> >>
> >>
> >> *From:* rietveld_l-requ...@ill.fr  *On
> Behalf
> >> Of *Bish, David L
> >> *Sent:* Sunday, September 3, 2023 7:08 AM
> >> *To:* Shay Tirosh ; Fernando Igoa <
> >> fer.igoa.1...@gmail.com>
> >> *Cc:* Rietveld List (rietveld_l@ill.fr) 
> >> *Subject:* [EXT] Re: [External] Re: Step-like basline
> >>
> >>
> >>
> >> Some people who received this message don't often get email from
> >> b...@indiana.edu. Learn why this is important
> >> <
> https://urldefense.com/v3/__https:/aka.ms/LearnAboutSenderIdentification__;!!IKRxdwAv5BmarQ!fFhSHn4S5iEzkW-O9lvWG-OzoqK_2SKhRniGa71nxuOL3GcxiyD83i2mnNN0Z48HPkn4zjKqH-aqqA$
> >
> >>
> >> Hello Shay,
> >>
> >> I think it is probably related to "tube tails". You can read about this
> in
> >> the literature (e.g., on the BGMN web site) and you can model it in some
> >> Rietveld software such as Topas. You don't normally notice this but it
> >> becomes apparent with higher-intensity peaks.
> >>
> >>
> >>
> >> Regards,
> >>
> >> Dave
> >> --
> >>
> >> *From:* rietveld_l-requ...@ill.fr  on behalf
> >> of Fernando Igoa 
> >> *Sent:* Sunday, September 3, 2023 3:06 AM
> >> *To:* Shay Tirosh 
> >> *Cc:* Rietveld List (rietveld_l@ill.fr) 
> >> *Subject:* [External] Re: Step-like basline
> >>
> >>
> >>
> >> This message was sent from a non-IU address. Please exercise caution
> when
> >> clicking links or opening attachments from external sources.
> >>
> >>
> >>
> >> Hey Shay,
> >>
> >>
> >>
> >> Are you using a motorized slit during the measurement? These may open up
> >> abruptly to compensate for the angular dependence of the footprint and
> thus
> >> generate an abrupt increase in the intensity.
> >>
> >>
> >>
> >> Hope it helps :)
> >>
> >>
> >>
> >> On Sun, Sep 3, 2023, 8:50 AM Shay Tirosh  wrote:
> >>
> >> Dear Rietvelders
> >>
> >> I am attaching a zoom-in on a diffraction profile.
> >>
> >> My question is what is the origin of the step-like profile next to a
> very
> >> large reflection peak?
> >>
> >> Is it a sample preparation problem?
> >>
> >> Is it part of the baseline?
> >>
> >> Thanks
> >>
> >> Shay
> >>
> >> --
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> ++
> >> Please do NOT attach files to the whole list
>  >> >
> >> Send commands to

RE: [EXT] Re: [External] Re: Step-like basline

[alancoelho]

Hi Kurt

 

TOPAS models absorption edges well. Page 158 of the Technical Reference at
http://www.topas-academic.net/Technical_Reference.pdf shows the result. 

 

The macro in question is modifies the emission profile which is how I think
it should be modelled:

 

macro Absorption_Edge_Correction_Eqn(& edge, & a_white, & b_white, & a_erf,
& edge_extra)

   {

  modify_peak_eqn =

 (

Get(current_peak) +

a_white Exp(- b_white (Get(current_peak_x) - edge)^2) / Tan(Th)

' Not necessary

' If(Get(current_peak_x) < edge, 1/Get(current_peak_x)^3, 1 )

 )

 (edge_extra + 0.5 (1 + Erf_Approx( a_erf (Get(current_peak_x) -
edge))) );

   }

 

If someone spots a problem then I would be happy to know. The line commented
out is due to the fact it makes little difference to the result. 

 

Cheers

Alan

 

From: rietveld_l-requ...@ill.fr  On Behalf Of
Kurt Leinenweber
Sent: Monday, September 4, 2023 2:53 AM
To: Thomas Gegan ; Bish, David L ;
Shay Tirosh ; Fernando Igoa 
Cc: Rietveld List (rietveld_l@ill.fr) 
Subject: RE: [EXT] Re: [External] Re: Step-like basline

 

Hi,  Are these things modeled in Rietveld programs, by chance?  It seems
like a lot of baggage to put in a refinement but if it makes the results
better.

 

*   Kurt

 

From: rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@ill.fr> > On Behalf Of
Thomas Gegan
Sent: Sunday, September 3, 2023 9:16 AM
To: Bish, David L mailto:b...@indiana.edu> >; Shay Tirosh
mailto:stiro...@gmail.com> >; Fernando Igoa
mailto:fer.igoa.1...@gmail.com> >
Cc: Rietveld List (rietveld_l@ill.fr  )
mailto:rietveld_l@ill.fr> >
Subject: RE: [EXT] Re: [External] Re: Step-like basline

 

I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.

 

Tom Gegan
Chemist III

 

Phone: +1 732 205-5111, Email:  
tom.ge...@basf.com
Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830
Iselin, United States



 

From: rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@ill.fr> > On Behalf Of
Bish, David L
Sent: Sunday, September 3, 2023 7:08 AM
To: Shay Tirosh mailto:stiro...@gmail.com> >; Fernando
Igoa mailto:fer.igoa.1...@gmail.com> >
Cc: Rietveld List (rietveld_l@ill.fr  )
mailto:rietveld_l@ill.fr> >
Subject: [EXT] Re: [External] Re: Step-like basline

 


Some people who received this message don't often get email from
b...@indiana.edu  . Learn why this is important
 



Hello Shay,

I think it is probably related to "tube tails". You can read about this in
the literature (e.g., on the BGMN web site) and you can model it in some
Rietveld software such as Topas. You don't normally notice this but it
becomes apparent with higher-intensity peaks.

 

Regards,

Dave

  _  

From: rietveld_l-requ...@ill.fr 
mailto:rietveld_l-requ...@ill.fr> > on behalf of
Fernando Igoa mailto:fer.igoa.1...@gmail.com> >
Sent: Sunday, September 3, 2023 3:06 AM
To: Shay Tirosh mailto:stiro...@gmail.com> >
Cc: Rietveld List (rietveld_l@ill.fr  )
mailto:rietveld_l@ill.fr> >
Subject: [External] Re: Step-like basline 

 

This message was sent from a non-IU address. Please exercise caution when
clicking links or opening attachments from external sources.

 

Hey Shay, 

 

Are you using a motorized slit during the measurement? These may open up
abruptly to compensate for the angular dependence of the footprint and thus
generate an abrupt increase in the intensity. 

 

Hope it helps :)

 

On Sun, Sep 3, 2023, 8:50 AM Shay Tirosh mailto:stiro...@gmail.com> > wrote:

Dear Rietvelders 

I am attaching a zoom-in on a diffraction profile. 

My question is what is the origin of the step-like profile next to a very
large reflection peak?

Is it a sample preparation problem?

Is it part of the baseline? 



Thanks

Shay

-- 

 

 

 

 

 

++
Please do NOT attach files to the whole list mailto:alan.he...@neutronoptics.com> >
Send commands to mailto:lists...@ill.fr> > eg: HELP as the
subject with no body text
The Rietveld_L list archive is on
http://www.mail-archive.com/rietveld_l@ill.fr/
 
++

++
Please do NOT attach files to the whole list 
Send commands to  eg: HELP as the subject with no body text
The Rietveld_L list archive is on 

Re: [EXT] Re: [External] Re: Step-like basline

[Frank Girgsdies]

Dear Alan,

Is this updated macro downward compatible with TOPAS version 5?

If yes, I would edit my topas.inc and try it.

Thanks and cheers,
Frank

On 04.09.2023 10:44, alancoe...@bigpond.com wrote:

Hi Kurt

TOPAS models absorption edges well. Page 158 of the Technical Reference 
at http://www.topas-academic.net/Technical_Reference.pdf 
 shows the result.


The macro in question is modifies the emission profile which is how I 
think it should be modelled:


macro Absorption_Edge_Correction_Eqn(& edge, & a_white, & b_white, & 
a_erf, & edge_extra)


    {

   modify_peak_eqn =

  (

     Get(current_peak) +

     a_white Exp(- b_white (Get(current_peak_x) - edge)^2) / Tan(Th)

     ' Not necessary

     ' If(Get(current_peak_x) < edge, 1/Get(current_peak_x)^3, 1 )

  )

  (edge_extra + 0.5 (1 + Erf_Approx( a_erf (Get(current_peak_x) 
- edge))) );


    }

If someone spots a problem then I would be happy to know. The line 
commented out is due to the fact it makes little difference to the result.


Cheers

Alan

*From:*rietveld_l-requ...@ill.fr  *On Behalf 
Of *Kurt Leinenweber

*Sent:* Monday, September 4, 2023 2:53 AM
*To:* Thomas Gegan ; Bish, David L 
; Shay Tirosh ; Fernando Igoa 


*Cc:* Rietveld List (rietveld_l@ill.fr) 
*Subject:* RE: [EXT] Re: [External] Re: Step-like basline

Hi,  Are these things modeled in Rietveld programs, by chance?  It seems 
like a lot of baggage to put in a refinement but if it makes the results 
better…


  * Kurt

*From:*rietveld_l-requ...@ill.fr  
mailto:rietveld_l-requ...@ill.fr>> *On 
Behalf Of *Thomas Gegan

*Sent:* Sunday, September 3, 2023 9:16 AM
*To:* Bish, David L mailto:b...@indiana.edu>>; Shay 
Tirosh mailto:stiro...@gmail.com>>; Fernando Igoa 
mailto:fer.igoa.1...@gmail.com>>
*Cc:* Rietveld List (rietveld_l@ill.fr ) 
mailto:rietveld_l@ill.fr>>

*Subject:* RE: [EXT] Re: [External] Re: Step-like basline

I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.

*Tom Gegan*
Chemist III

Phone: +1 732 205-5111, Email: tom.ge...@basf.com 

Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830 
Iselin, United States


*From:*rietveld_l-requ...@ill.fr  
mailto:rietveld_l-requ...@ill.fr>> *On 
Behalf Of *Bish, David L

*Sent:* Sunday, September 3, 2023 7:08 AM
*To:* Shay Tirosh mailto:stiro...@gmail.com>>; 
Fernando Igoa mailto:fer.igoa.1...@gmail.com>>
*Cc:* Rietveld List (rietveld_l@ill.fr ) 
mailto:rietveld_l@ill.fr>>

*Subject:* [EXT] Re: [External] Re: Step-like basline



Some people who received this message don't often get email from 
b...@indiana.edu . Learn why this is important 





Hello Shay,

I think it is probably related to "tube tails". You can read about this 
in the literature (e.g., on the BGMN web site) and you can model it in 
some Rietveld software such as Topas. You don't normally notice this but 
it becomes apparent with higher-intensity peaks.


Regards,

Dave



*From:*rietveld_l-requ...@ill.fr  
mailto:rietveld_l-requ...@ill.fr>> on behalf 
of Fernando Igoa mailto:fer.igoa.1...@gmail.com>>

*Sent:* Sunday, September 3, 2023 3:06 AM
*To:* Shay Tirosh mailto:stiro...@gmail.com>>
*Cc:* Rietveld List (rietveld_l@ill.fr ) 
mailto:rietveld_l@ill.fr>>

*Subject:* [External] Re: Step-like basline

This message was sent from a non-IU address. Please exercise caution 
when clicking links or opening attachments from external sources.


Hey Shay,

Are you using a motorized slit during the measurement? These may open up 
abruptly to compensate for the angular dependence of the footprint and 
thus generate an abrupt increase in the intensity.


Hope it helps :)

On Sun, Sep 3, 2023, 8:50 AM Shay Tirosh > wrote:


Dear Rietvelders

I am attaching a zoom-in on a diffraction profile.

My question is what is the origin of the step-like profile next to a
very large reflection peak?

Is it a sample preparation problem?

Is it part of the baseline?

Thanks

Shay

-- 


++
Please do NOT attach files to the whole list
mailto:alan.he...@neutronoptics.com>>
Send commands to mailto:lists...@ill.fr>> eg: HELP
as the subject with no body text
The Rietveld_L list archive is on
http://www.mail-archive.com/rietveld_l@ill.fr/

RE: [EXT] Re: [External] Re: Step-like basline

[alancoelho]

Yes Frank, the macro is working with V5 of TOPAS-Academic; TOPAS should be the 
same.

Cheers

Alan

 

-Original Message-
From: Frank Girgsdies  
Sent: Monday, September 4, 2023 7:09 PM
To: alancoe...@bigpond.com
Cc: rietveld_l@ill.fr
Subject: Re: [EXT] Re: [External] Re: Step-like basline

 

Dear Alan,

 

Is this updated macro downward compatible with TOPAS version 5?

 

If yes, I would edit my topas.inc and try it.

 

Thanks and cheers,

Frank

 

On 04.09.2023 10:44,   alancoe...@bigpond.com 
wrote:

> Hi Kurt

> 

> TOPAS models absorption edges well. Page 158 of the Technical 

> Reference at   
> http://www.topas-academic.net/Technical_Reference.pdf

> <  
> http://www.topas-academic.net/Technical_Reference.pdf> shows the result.

> 

> The macro in question is modifies the emission profile which is how I 

> think it should be modelled:

> 

> macro Absorption_Edge_Correction_Eqn(& edge, & a_white, & b_white, & 

> a_erf, & edge_extra)

> 

> {

> 

>modify_peak_eqn =

> 

>   (

> 

>  Get(current_peak) +

> 

>  a_white Exp(- b_white (Get(current_peak_x) - edge)^2) / 

> Tan(Th)

> 

>  ' Not necessary

> 

>  ' If(Get(current_peak_x) < edge, 1/Get(current_peak_x)^3, 

> 1 )

> 

>   )

> 

>   (edge_extra + 0.5 (1 + Erf_Approx( a_erf 

> (Get(current_peak_x)

> - edge))) );

> 

> }

> 

> If someone spots a problem then I would be happy to know. The line 

> commented out is due to the fact it makes little difference to the result.

> 

> Cheers

> 

> Alan

> 

> *From:*rietveld_l-requ...@ill.fr <  
> rietveld_l-requ...@ill.fr> *On 

> Behalf Of *Kurt Leinenweber

> *Sent:* Monday, September 4, 2023 2:53 AM

> *To:* Thomas Gegan <  tom.ge...@basf.com>; Bish, 
> David L 

> <  b...@indiana.edu>; Shay Tirosh < 
>  stiro...@gmail.com>; Fernando Igoa 

> <  fer.igoa.1...@gmail.com>

> *Cc:* Rietveld List (  rietveld_l@ill.fr) < 
>  rietveld_l@ill.fr>

> *Subject:* RE: [EXT] Re: [External] Re: Step-like basline

> 

> Hi,  Are these things modeled in Rietveld programs, by chance?  It 

> seems like a lot of baggage to put in a refinement but if it makes the 

> results better…

> 

>   * Kurt

> 

> *From:*rietveld_l-requ...@ill.fr <  
> mailto:rietveld_l-requ...@ill.fr>

> <  
> rietveld_l-requ...@ill.fr > *On 

> Behalf Of *Thomas Gegan

> *Sent:* Sunday, September 3, 2023 9:16 AM

> *To:* Bish, David L <  
> b...@indiana.edu >; Shay 

> Tirosh <  
> stiro...@gmail.com >; Fernando Igoa 

> <  
> fer.igoa.1...@gmail.com >

> *Cc:* Rietveld List (  rietveld_l@ill.fr < 
>  mailto:rietveld_l@ill.fr>) 

> <  rietveld_l@ill.fr 
> >

> *Subject:* RE: [EXT] Re: [External] Re: Step-like basline

> 

> I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.

> 

> *Tom Gegan*

> Chemist III

> 

> Phone: +1 732 205-5111, Email:   
> tom.ge...@basf.com 

> <  mailto:tom.ge...@basf.com> Postal Address: BASF 
> Corporation, , 25 

> Middlesex Essex Turnpike, 08830 Iselin, United States

> 

> *From:*rietveld_l-requ...@ill.fr <  
> mailto:rietveld_l-requ...@ill.fr>

> <  
> rietveld_l-requ...@ill.fr > *On 

> Behalf Of *Bish, David L

> *Sent:* Sunday, September 3, 2023 7:08 AM

> *To:* Shay Tirosh < 
>  stiro...@gmail.com 
> >; 

> Fernando Igoa  <  mailto:fer.igoa.1...@gmail.com>>

> *Cc:* Rietveld List (  rietveld_l@ill.fr < 
>  mailto:rietveld_l@ill.fr>) 

> <  rietveld_l@ill.fr 
> >

> *Subject:* [EXT] Re: [External] Re: Step-like basline

> 

> 

> 

> Some people who received this message don't often get email from 

>   b...@indiana.edu < 

Re: [EXT] Re: [External] Re: Step-like basline

[Reinhard Kleeberg]

Alan, I'm quite sure that Shay's pattern shows the typical profile for  
a profile standard or any "highly crystalline" material measured with  
a standard configuration of his instrument. No problem with sample  
prep, no chance for improvement by modified instrumental setting  
(thicker filter would reduce K beta but make the Ni absorbtion edge  
more prominent). Unfortunately, lab instruments with "fast" 1D  
detectors with high intensity efficiency but bad energy resolution  
demanding for K beta filtering seem to be now the "quasi standard" on  
the market. Low noise patterns can be measured in short time, but the  
distorted profiles are hard to fit by simple standard profiles in a  
similar quality. From this point of view it makes sense to find a  
working approach for fitting the data of such machines, too.


However, I got several measurements showing Co or Cu K beta remnants  
from users despite the manufacturer has claimed that the good energy  
resolution of their detector (no names here!) alone would remove K  
beta "completely". Sometimes the customers were adviced by the company  
cases to insert an additional filter, and the "edge problem" is back...


Btw, I learned that even traditional secondary-beam curved graphite  
002 monochromators are not always able to resolve a completely "clean"  
Cu K alpha1/2 doublet: As the W L alpha wavelength is close to Cu K  
alpha, in unfortunate cases (crystal quality or alignment) even such  
machines may produce measurable/visible W L satellites when old tubes  
are in use. For economic reasons, some people prefer to add a scalable  
W L satellite peak in the BGMN wavelength model instead of buying a  
new tube...


Personally, I love my Peltier cooled 0D Si drift detectors. They  
really can completely suppress K beta and even remove any W L from Cu  
K alpha, no need for scalable satellite peaks in the profile model.  
Just some minor "wavelength feets" must be added to approximate the  
ROI window. Practically, the profiles are comparable with the ones  
obtained by a classical well aligned graphite monochromator plus  
szintillation counter, but with 5 times more intensity. And the  
detector may be used for some qualitative XRF (of course elements from  
K- only, as in air).


Reinhard

Zitat von Alan W Hewat :


Reinhard is right that it is best to improve the instrument to produce
cleaner data. I'm concerned about the advice to model all kinds of features
whose origin is not fully understood, simply to obtain a better fit. Shay
has told us nothing about his instrument or his conditions of data
collection. He asks "Is it a sample preparation problem", to which
the obvious reply is "Do you see this with other samples or different
materials" ? Only he can answer that. If the answer is yes, he might try
modifying his instrument (remove filters etc) to see what effect that has
on the pattern from a simple well characterised material. Again only he can
do that. Data collection is an experimental science, and data refinement
should not be reduced to a "black box" computer program where extra
parameters can be added to reduce the R-factor.
Alan.

On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg <
kleeb...@mineral.tu-freiberg.de> wrote:


Can be modeled in the BGMN peak profile model as well, by modifying
the *.lam file by a series of additional Lorentzians on the 1/lambda
scale, see figure.
The same can be done for other spectral impurities, e.g. W L
satellites. Also "electronic effects" on the wavelength distribution
profile like the "edges" from the ROI settings of Si drift detectors
can be modelled in such a convolution based approach.
However, better to have a pure/simple wavelength distribution (clear
alpha1/2 doublet) by a monochromator or high energy resolution
detector, as any satellites make trouble in trace phase analysis and
do cause prolonged calculation time in complicated Rietveld refinements.

Reinhard



Zitat von Matthew Rowles :

> Topas can model them quite well. The functionality was introduced in
> version 5.
>
> On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:
>
>> Hi,  Are these things modeled in Rietveld programs, by chance?  It seems
>> like a lot of baggage to put in a refinement but if it makes the results
>> better…
>>
>>
>>
>>- Kurt
>>
>>
>>
>> *From:* rietveld_l-requ...@ill.fr  *On
Behalf
>> Of *Thomas Gegan
>> *Sent:* Sunday, September 3, 2023 9:16 AM
>> *To:* Bish, David L ; Shay Tirosh ;
>> Fernando Igoa 
>> *Cc:* Rietveld List (rietveld_l@ill.fr) 
>> *Subject:* RE: [EXT] Re: [External] Re: Step-like basline
>>
>>
>>
>> I agree with a Ni absorption edge, possibly with a Kβ peak around 38°
2θ.
>>
>>
>>
>> *Tom Gegan*
>> Chemist III
>>
>>
>>
>> Phone: +1 732 205-5111, Email: tom.ge...@basf.com
>> Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830
>> Iselin, United States
>>
>>
>>
>> *From:* rietveld_l-requ...@ill.fr  *On
Behalf
>> Of *Bish, David L
>> *Sent:* Sunday, September 3, 2023 7:08 AM
>>

Re: Re[2]: [EXT] Re: [External] Re: Step-like basline

[Reinhard Kleeberg]

Dear Habib,
the phenomenom "satellites or edges" originates from the diffraction  
process. The critical parameters are:
- spectral pureness of the primary beam (primary beam monochromator,  
tube spectral contamination like W...)

- the use of K beta absorbtion filter (and its thickness)
- the energy resolution ("window") of the detector system.
Even a D8 system may be equipped with different types of detectors,  
slits and energy limits can be set differently for an identical  
configuration, and quite often satellite peaks may appear later in the  
time of use (aging of the tube produces more W L, Fe filters may  
corrode and get perforated...). So it is strictly recommended to check  
the instrument peridically, by measuring a full pattern of a profile  
standard (LaB6 or Si or similar).

Greetings
Reinhard

Zitat von Habib Boughzala :


Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or  
controlled diffusion) material this kind of phenomenon is visible  
around the highest reflection, especially when the preferred  
orientation is drastically present.


So, in my opinion, Reinhard and Alan are right,  and what is  
observed is just like reflections broadening, asymmetry, shifting  
...etc ... and can be related to the material behavior.
Now, what is the physical (crystallographic!) property responsible  
of this phenomenon? let's open the floor for a large discussion.



Habib


-- Message d'origine --
De "Alan W Hewat" 
À "Reinhard Kleeberg" 
Cc rietveld_l@ill.fr
Date 04/09/2023 09:29:08
Objet Re: [EXT] Re: [External] Re: Step-like basline

Reinhard is right that it is best to improve the instrument to  
produce cleaner data. I'm concerned about the advice to model all  
kinds of features whose origin is not fully understood, simply to  
obtain a better fit. Shay has told us nothing about his instrument  
or his conditions of data collection. He asks "Is it a sample  
preparation problem", to which the obvious reply is "Do you see  
this with other samples or different materials" ? Only he can  
answer that. If the answer is yes, he might try modifying his  
instrument (remove filters etc) to see what effect that has on the  
pattern from a simple well characterised material. Again only he  
can do that. Data collection is an experimental science, and data  
refinement should not be reduced to a "black box" computer program  
where extra parameters can be added to reduce the R-factor.

Alan.

On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg  
 wrote:

Can be modeled in the BGMN peak profile model as well, by modifying
the *.lam file by a series of additional Lorentzians on the 1/lambda
scale, see figure.
The same can be done for other spectral impurities, e.g. W L
satellites. Also "electronic effects" on the wavelength distribution
profile like the "edges" from the ROI settings of Si drift detectors
can be modelled in such a convolution based approach.
However, better to have a pure/simple wavelength distribution (clear
alpha1/2 doublet) by a monochromator or high energy resolution
detector, as any satellites make trouble in trace phase analysis and
do cause prolonged calculation time in complicated Rietveld refinements.

Reinhard



Zitat von Matthew Rowles :


Topas can model them quite well. The functionality was introduced in
version 5.

On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:


Hi,  Are these things modeled in Rietveld programs, by chance?  It seems
like a lot of baggage to put in a refinement but if it makes the results
better…



   - Kurt



*From:* rietveld_l-requ...@ill.fr  *On Behalf
Of *Thomas Gegan
*Sent:* Sunday, September 3, 2023 9:16 AM
*To:* Bish, David L ; Shay Tirosh ;
Fernando Igoa 
*Cc:* Rietveld List (rietveld_l@ill.fr) 
*Subject:* RE: [EXT] Re: [External] Re: Step-like basline



I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.



*Tom Gegan*
Chemist III



Phone: +1 732 205-5111, Email: tom.ge...@basf.com
Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830
Iselin, United States



*From:* rietveld_l-requ...@ill.fr  *On Behalf
Of *Bish, David L
*Sent:* Sunday, September 3, 2023 7:08 AM
*To:* Shay Tirosh ; Fernando Igoa <
fer.igoa.1...@gmail.com>
*Cc:* Rietveld List (rietveld_l@ill.fr) 
*Subject:* [EXT] Re: [External] Re: Step-like basline



Some people who received this message don't often get email from
b...@indiana.edu. Learn why this is important


Hello Shay,

I think it is probably related to "tube tails". You can read  
about this in

the literature (e.g., on the BGMN web site) and you can model it in some
Rietveld software such as Topas. You don't normally notice this but it
becomes appare

Re: Step-like basline

[Habib Boughzala]

Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or controlled 
diffusion) material this kind of phenomenon is visible around the 
highest reflection, especially when the preferred orientation is 
drastically present.


So, in my opinion, Reinhard and Alan are right,  and what is observed is 
just like reflections broadening, asymmetry, shifting ...etc ... and can 
be related to the material behavior.
Now, what is the physical (crystallographic!) property responsible of 
this phenomenon? let's open the floor for a large discussion.



Habib++
Please do NOT attach files to the whole list 
Send commands to  eg: HELP as the subject with no body text
The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/
++

Re: Step-like basline

[Reinhard Kleeberg]

Habib,
obviously your instrument is equipped with a not cooled solid state 1D  
detector (maybe Bruker Lynxeye?) and a Ni filter what is used for  
"selective" absorbtion of the Cu K beta radiation.
What you see in the pattern is mainly a significant part of the tube  
emission spectrum, diffracted at the Si 111 plane, and modified by the  
Ni K absorption edge.
The peak at ~ 25.8 ° is the remnant Si 111 diffracting the Cu Kbeta1  
wavelength 1.39223 A.
The edge is the Ni K absorbtion edge (I don't know the wavelength of  
the edge exactly, ~ 1.49 A), and the doublet at ~ 28.4 ° is the Si 111  
diffracting the Cu K alpha1 and alpha2, 1.54059 and 1.54443 A,  
respectively.
The asymmetric slope of the background on the rigth side of the peak  
is the unfiltered part of the Bremsstrahlung, their low energy part  
what is not more cut by the Ni absorbtion.
As your wafer is a perfect Si 111 plane you get extreme intensity and  
< 1 % intensity effects become clearly visible. Maybe you have seen a  
Si powder pattern what appeared to be "clean", but if you would have  
measured the powder pattern with better counting statistics, your Si  
111 region would look quite similar.

Greetings

Reinhard

Zitat von Habib Boughzala :


Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or  
controlled diffusion) material this kind of phenomenon is visible  
around the highest reflection, especially when the preferred  
orientation is drastically present.


So, in my opinion, Reinhard and Alan are right,  and what is  
observed is just like reflections broadening, asymmetry, shifting  
...etc ... and can be related to the material behavior.
Now, what is the physical (crystallographic!) property responsible  
of this phenomenon? let's open the floor for a large discussion.



Habib



--
TU Bergakademie Freiberg
Dr. R. Kleeberg
Mineralogisches Labor
Brennhausgasse 14
D-09596 Freiberg

Tel. ++49 (0) 3731-39-3244
Fax. ++49 (0) 3731-39-3129

++
Please do NOT attach files to the whole list 
Send commands to  eg: HELP as the subject with no body text
The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/
++

Re: [EXTERNAL] Re: Step-like basline

[Payzant, Andrew]

Habib,

Reinhard has nailed it – no need for a larger discussion as these artifacts are 
well understood. The late William Parrish published a paper describing these 
sort of artifacts ages ago (maybe 1950’s?).

Andrew
---
Dr. E. Andrew Payzant, FASM
Distinguished R&D Staff Member
Leader, Materials Engineering Group
Neutron Scattering Division

Mailing Address:
Oak Ridge National Laboratory
P.O. Box 2008
Building 8600, MS 6475
Oak Ridge, TN, 37831

Cell: (865) 235-4981
Email: payza...@ornl.gov
https://www.ornl.gov/staff-profile/e-andrew-payzant



From: rietveld_l-requ...@ill.fr  on behalf of 
Reinhard Kleeberg 
Date: Monday, September 4, 2023 at 10:47 AM
To: Habib Boughzala 
Cc: rietveld_l-requ...@ill.fr , rietveld_l@ill.fr 

Subject: [EXTERNAL] Re: Step-like basline
Habib,
obviously your instrument is equipped with a not cooled solid state 1D
detector (maybe Bruker Lynxeye?) and a Ni filter what is used for
"selective" absorbtion of the Cu K beta radiation.
What you see in the pattern is mainly a significant part of the tube
emission spectrum, diffracted at the Si 111 plane, and modified by the
Ni K absorption edge.
The peak at ~ 25.8 ° is the remnant Si 111 diffracting the Cu Kbeta1
wavelength 1.39223 A.
The edge is the Ni K absorbtion edge (I don't know the wavelength of
the edge exactly, ~ 1.49 A), and the doublet at ~ 28.4 ° is the Si 111
diffracting the Cu K alpha1 and alpha2, 1.54059 and 1.54443 A,
respectively.
The asymmetric slope of the background on the rigth side of the peak
is the unfiltered part of the Bremsstrahlung, their low energy part
what is not more cut by the Ni absorbtion.
As your wafer is a perfect Si 111 plane you get extreme intensity and
< 1 % intensity effects become clearly visible. Maybe you have seen a
Si powder pattern what appeared to be "clean", but if you would have
measured the powder pattern with better counting statistics, your Si
111 region would look quite similar.
Greetings

Reinhard

Zitat von Habib Boughzala :

> Dear all,
> I would like to send you my witness related to this kind of observation.
> I can assure that our Bruker D8 is clean and optimized!
>
> In many cases of well conditioned thin film (spin coating or
> controlled diffusion) material this kind of phenomenon is visible
> around the highest reflection, especially when the preferred
> orientation is drastically present.
>
> So, in my opinion, Reinhard and Alan are right,  and what is
> observed is just like reflections broadening, asymmetry, shifting
> ...etc ... and can be related to the material behavior.
> Now, what is the physical (crystallographic!) property responsible
> of this phenomenon? let's open the floor for a large discussion.
>
>
> Habib


--
TU Bergakademie Freiberg
Dr. R. Kleeberg
Mineralogisches Labor
Brennhausgasse 14
D-09596 Freiberg

Tel. ++49 (0) 3731-39-3244
Fax. ++49 (0) 3731-39-3129
++
Please do NOT attach files to the whole list 
Send commands to  eg: HELP as the subject with no body text
The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/
++

Re[4]: [EXT] Re: [External] Re: Step-like basline

[Habib Boughzala]

Many thanks Reinhard,

That's exactly what I wanted to say by  "I can assure that our Bruker D8 
is clean and optimized!"
Otherwise, in some other cases of well conditioned thin film no similar 
phenomenon is observed!

So, yes, it's obviously possible that your point of view is right.

Regards
Habib


-- Message d'origine --
De "Reinhard Kleeberg" 
À "Habib Boughzala" 
Cc rietveld_l@ill.fr
Date 04/09/2023 11:07:50
Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline


Dear Habib,
the phenomenom "satellites or edges" originates from the diffraction  process. 
The critical parameters are:
- spectral pureness of the primary beam (primary beam monochromator,  tube 
spectral contamination like W...)
- the use of K beta absorbtion filter (and its thickness)
- the energy resolution ("window") of the detector system.
Even a D8 system may be equipped with different types of detectors,  slits and 
energy limits can be set differently for an identical  configuration, and quite 
often satellite peaks may appear later in the  time of use (aging of the tube 
produces more W L, Fe filters may  corrode and get perforated...). So it is 
strictly recommended to check  the instrument peridically, by measuring a full 
pattern of a profile  standard (LaB6 or Si or similar).
Greetings
Reinhard

Zitat von Habib Boughzala :


Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or  controlled 
diffusion) material this kind of phenomenon is visible  around the highest 
reflection, especially when the preferred  orientation is drastically present.

So, in my opinion, Reinhard and Alan are right,  and what is  observed is just 
like reflections broadening, asymmetry, shifting  ...etc ... and can be related 
to the material behavior.
Now, what is the physical (crystallographic!) property responsible  of this 
phenomenon? let's open the floor for a large discussion.


Habib


-- Message d'origine --
De "Alan W Hewat" 
À "Reinhard Kleeberg" 
Cc rietveld_l@ill.fr
Date 04/09/2023 09:29:08
Objet Re: [EXT] Re: [External] Re: Step-like basline


Reinhard is right that it is best to improve the instrument to  produce cleaner data. I'm concerned about the 
advice to model all  kinds of features whose origin is not fully understood, simply to  obtain a better fit. 
Shay has told us nothing about his instrument  or his conditions of data collection. He asks "Is it a 
sample  preparation problem", to which the obvious reply is "Do you see  this with other samples or 
different materials" ? Only he can  answer that. If the answer is yes, he might try modifying his  
instrument (remove filters etc) to see what effect that has on the  pattern from a simple well characterised 
material. Again only he  can do that. Data collection is an experimental science, and data  refinement should 
not be reduced to a "black box" computer program  where extra parameters can be added to reduce the 
R-factor.
Alan.

On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg  
 wrote:

Can be modeled in the BGMN peak profile model as well, by modifying
the *.lam file by a series of additional Lorentzians on the 1/lambda
scale, see figure.
The same can be done for other spectral impurities, e.g. W L
satellites. Also "electronic effects" on the wavelength distribution
profile like the "edges" from the ROI settings of Si drift detectors
can be modelled in such a convolution based approach.
However, better to have a pure/simple wavelength distribution (clear
alpha1/2 doublet) by a monochromator or high energy resolution
detector, as any satellites make trouble in trace phase analysis and
do cause prolonged calculation time in complicated Rietveld refinements.

Reinhard



Zitat von Matthew Rowles :


Topas can model them quite well. The functionality was introduced in
version 5.

On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:


Hi,  Are these things modeled in Rietveld programs, by chance?  It seems
like a lot of baggage to put in a refinement but if it makes the results
better…



   - Kurt



*From:* rietveld_l-requ...@ill.fr  *On Behalf
Of *Thomas Gegan
*Sent:* Sunday, September 3, 2023 9:16 AM
*To:* Bish, David L ; Shay Tirosh ;
Fernando Igoa 
*Cc:* Rietveld List (rietveld_l@ill.fr) 
*Subject:* RE: [EXT] Re: [External] Re: Step-like basline



I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.



*Tom Gegan*
Chemist III



Phone: +1 732 205-5111, Email: tom.ge...@basf.com
Postal Address: BASF Corporation, , 25 Middlesex Essex Turnpike, 08830
Iselin, United States



*From:* rietveld_l-requ...@ill.fr  *On Behalf
Of *Bish, David L
*Sent:* Sunday, September 3, 2023 7:08 AM
*To:* Shay Tirosh ; Fernando Igoa <
fer.igoa.1...@gmail.com>
*Cc:* Rietveld List (rietveld_l@ill.fr) 
*Subject:* [EXT] Re: [External] Re: Step-like basline



Some people who received this message don't often get em

Re: [EXT] [External] Re: Step-like basline

[Luca Lutterotti]

Dear Habib,

Reinhard is right, and what he explained is exactly what you observed. Now I 
would add that I may not define your Bruker clean and optimised, because for 
this kind of samples, wafers and extremely textured thin films, it would be 
better to have a monochromator in the incident beam and not a Ni filtered (I 
would more say it is a requirement). It was already showed many times in the 
past as a monochromator in the incident beam is a necessity for this materials 
to avoid all the "physical artifacts" created by the strong intensity and not 
clean Kalpha radiation.

Best regards,

Luca

 

Luca Lutterotti
Dipartimento di Ingegneria Industriale
Università di Trento
via Sommarive, 9 - 38123 Trento (Italy)
tel. +39 0461 2824-14 (Office), -34 (X-Ray lab)




Maud: http://maud.radiographema.com 


> On 4 Sep 2023, at 12:20, Habib Boughzala  wrote:
> 
> Many thanks Reinhard,
> 
> That's exactly what I wanted to say by  "I can assure that our Bruker D8 is 
> clean and optimized!"
> Otherwise, in some other cases of well conditioned thin film no similar 
> phenomenon is observed!
> So, yes, it's obviously possible that your point of view is right.
> 
> Regards
> Habib
> 
> 
> -- Message d'origine --
> De "Reinhard Kleeberg"  >
> À "Habib Boughzala" mailto:boughz...@yahoo.com>>
> Cc rietveld_l@ill.fr 
> Date 04/09/2023 11:07:50
> Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline
> 
>> Dear Habib,
>> the phenomenom "satellites or edges" originates from the diffraction 
>> process. The critical parameters are:
>> - spectral pureness of the primary beam (primary beam monochromator, tube 
>> spectral contamination like W...)
>> - the use of K beta absorbtion filter (and its thickness)
>> - the energy resolution ("window") of the detector system.
>> Even a D8 system may be equipped with different types of detectors, slits 
>> and energy limits can be set differently for an identical configuration, and 
>> quite often satellite peaks may appear later in the time of use (aging of 
>> the tube produces more W L, Fe filters may corrode and get perforated...). 
>> So it is strictly recommended to check the instrument peridically, by 
>> measuring a full pattern of a profile standard (LaB6 or Si or similar).
>> Greetings
>> Reinhard
>>  
>> Zitat von Habib Boughzala mailto:boughz...@yahoo.com>>:
>>  
>>> Dear all,
>>> I would like to send you my witness related to this kind of observation.
>>> I can assure that our Bruker D8 is clean and optimized!
>>>  
>>> In many cases of well conditioned thin film (spin coating or controlled 
>>> diffusion) material this kind of phenomenon is visible around the highest 
>>> reflection, especially when the preferred orientation is drastically 
>>> present.
>>>  
>>> So, in my opinion, Reinhard and Alan are right, and what is observed is 
>>> just like reflections broadening, asymmetry, shifting ...etc ... and can be 
>>> related to the material behavior.
>>> Now, what is the physical (crystallographic!) property responsible of this 
>>> phenomenon? let's open the floor for a large discussion.
>>>  
>>>  
>>> Habib
>>>  
>>>  
>>> -- Message d'origine --
>>> De "Alan W Hewat" >> >
>>> À "Reinhard Kleeberg" >> >
>>> Cc rietveld_l@ill.fr 
>>> Date 04/09/2023 09:29:08
>>> Objet Re: [EXT] Re: [External] Re: Step-like basline
>>>  
 Reinhard is right that it is best to improve the instrument to produce 
 cleaner data. I'm concerned about the advice to model all kinds of 
 features whose origin is not fully understood, simply to obtain a better 
 fit. Shay has told us nothing about his instrument or his conditions of 
 data collection. He asks "Is it a sample preparation problem", to which 
 the obvious reply is "Do you see this with other samples or different 
 materials" ? Only he can answer that. If the answer is yes, he might try 
 modifying his instrument (remove filters etc) to see what effect that has 
 on the pattern from a simple well characterised material. Again only he 
 can do that. Data collection is an experimental science, and data 
 refinement should not be reduced to a "black box" computer program where 
 extra parameters can be added to reduce the R-factor.
 Alan.
  
 On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg 
 mailto:kleeb...@mineral.tu-freiberg.de>> 
 wrote:
> Can be modeled in the BGMN peak profile model as well, by modifying
> the *.lam file by a series of additional Lorentzians on the 1/lambda
> scale, see figure.
> The same can be done for other spectral impurities, e.g. W L
> satellites. Also "electronic effects" on the wavelength distribution
> profile like the "edges" from the ROI settings of Si drift detectors
>>

Re: Re[4]: [EXT] Re: [External] Re: Step-like basline

[Roberto de Avillez]

Dear Habib,

Run the silicon crystal diffraction without the Ni filter, you will confirm
Kleeberg's explanation.

Best regards,
Roberto de Avillez

Em seg., 4 de set. de 2023 às 07:20, Habib Boughzala <
habib.boughz...@ipein.rnu.tn> escreveu:

> Many thanks Reinhard,
>
> That's exactly what I wanted to say by  "I can assure that our Bruker D8
> is clean and optimized!"
> Otherwise, in some other cases of well conditioned thin film no similar
> phenomenon is observed!
> So, yes, it's obviously possible that your point of view is right.
>
> Regards
> Habib
>
>
> -- Message d'origine --
> De "Reinhard Kleeberg" 
> À "Habib Boughzala" 
> Cc rietveld_l@ill.fr
> Date 04/09/2023 11:07:50
> Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline
>
> Dear Habib,
> the phenomenom "satellites or edges" originates from the diffraction
> process. The critical parameters are:
> - spectral pureness of the primary beam (primary beam monochromator, tube
> spectral contamination like W...)
> - the use of K beta absorbtion filter (and its thickness)
> - the energy resolution ("window") of the detector system.
> Even a D8 system may be equipped with different types of detectors, slits
> and energy limits can be set differently for an identical configuration,
> and quite often satellite peaks may appear later in the time of use (aging
> of the tube produces more W L, Fe filters may corrode and get
> perforated...). So it is strictly recommended to check the instrument
> peridically, by measuring a full pattern of a profile standard (LaB6 or Si
> or similar).
> Greetings
> Reinhard
>
> Zitat von Habib Boughzala :
>
>
> Dear all,
> I would like to send you my witness related to this kind of observation.
> I can assure that our Bruker D8 is clean and optimized!
>
> In many cases of well conditioned thin film (spin coating or controlled
> diffusion) material this kind of phenomenon is visible around the highest
> reflection, especially when the preferred orientation is drastically
> present.
>
> So, in my opinion, Reinhard and Alan are right, and what is observed is
> just like reflections broadening, asymmetry, shifting ...etc ... and can be
> related to the material behavior.
> Now, what is the physical (crystallographic!) property responsible of this
> phenomenon? let's open the floor for a large discussion.
>
>
> Habib
>
>
> -- Message d'origine --
> De "Alan W Hewat" 
> À "Reinhard Kleeberg" 
> Cc rietveld_l@ill.fr
> Date 04/09/2023 09:29:08
> Objet Re: [EXT] Re: [External] Re: Step-like basline
>
>
> Reinhard is right that it is best to improve the instrument to produce
> cleaner data. I'm concerned about the advice to model all kinds of features
> whose origin is not fully understood, simply to obtain a better fit. Shay
> has told us nothing about his instrument or his conditions of data
> collection. He asks "Is it a sample preparation problem", to which the
> obvious reply is "Do you see this with other samples or different
> materials" ? Only he can answer that. If the answer is yes, he might try
> modifying his instrument (remove filters etc) to see what effect that has
> on the pattern from a simple well characterised material. Again only he can
> do that. Data collection is an experimental science, and data refinement
> should not be reduced to a "black box" computer program where extra
> parameters can be added to reduce the R-factor.
> Alan.
>
> On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg <
> kleeb...@mineral.tu-freiberg.de> wrote:
>
> Can be modeled in the BGMN peak profile model as well, by modifying
> the *.lam file by a series of additional Lorentzians on the 1/lambda
> scale, see figure.
> The same can be done for other spectral impurities, e.g. W L
> satellites. Also "electronic effects" on the wavelength distribution
> profile like the "edges" from the ROI settings of Si drift detectors
> can be modelled in such a convolution based approach.
> However, better to have a pure/simple wavelength distribution (clear
> alpha1/2 doublet) by a monochromator or high energy resolution
> detector, as any satellites make trouble in trace phase analysis and
> do cause prolonged calculation time in complicated Rietveld refinements.
>
> Reinhard
>
>
>
> Zitat von Matthew Rowles :
>
>
> Topas can model them quite well. The functionality was introduced in
> version 5.
>
> On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:
>
>
> Hi, Are these things modeled in Rietveld programs, by chance? It seems
> like a lot of baggage to put in a refinement but if it makes the results
> better…
>
>
>
> - Kurt
>
>
>
> *From:* rietveld_l-requ...@ill.fr  *On Behalf
> Of *Thomas Gegan
> *Sent:* Sunday, September 3, 2023 9:16 AM
> *To:* Bish, David L ; Shay Tirosh ;
> Fernando Igoa 
> *Cc:* Rietveld List (rietveld_l@ill.fr) 
> *Subject:* RE: [EXT] Re: [External] Re: Step-like basline
>
>
>
> I agree with a Ni absorption edge, possibly with a Kβ peak around 38° 2θ.
>
>
>
> *Tom Gegan*
> Chemist III
>
>
>
> Phone: +1 732 

Re: Re[4]: [EXT] Re: [External] Re: Step-like basline

[Alan W Hewat]

It's Shay who has the problem, not Habib, and we have heard nothing more
from him following his initial enquiry and all this expert advice.

Dr Alan Hewat, NeutronOptics
Grenoble, FRANCE (from phone)
alan.he...@neutronoptics.com
+33.476984168 VAT:FR79499450856
http://NeutronOptics.com/hewat
___


On Mon, 4 Sept 2023, 19:39 Roberto de Avillez,  wrote:

> Dear Habib,
>
> Run the silicon crystal diffraction without the Ni filter, you will
> confirm Kleeberg's explanation.
>
> Best regards,
> Roberto de Avillez
>
> Em seg., 4 de set. de 2023 às 07:20, Habib Boughzala <
> habib.boughz...@ipein.rnu.tn> escreveu:
>
>> Many thanks Reinhard,
>>
>> That's exactly what I wanted to say by  "I can assure that our Bruker D8
>> is clean and optimized!"
>> Otherwise, in some other cases of well conditioned thin film no similar
>> phenomenon is observed!
>> So, yes, it's obviously possible that your point of view is right.
>>
>> Regards
>> Habib
>>
>>
>> -- Message d'origine --
>> De "Reinhard Kleeberg" 
>> À "Habib Boughzala" 
>> Cc rietveld_l@ill.fr
>> Date 04/09/2023 11:07:50
>> Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline
>>
>> Dear Habib,
>> the phenomenom "satellites or edges" originates from the diffraction
>> process. The critical parameters are:
>> - spectral pureness of the primary beam (primary beam monochromator, tube
>> spectral contamination like W...)
>> - the use of K beta absorbtion filter (and its thickness)
>> - the energy resolution ("window") of the detector system.
>> Even a D8 system may be equipped with different types of detectors, slits
>> and energy limits can be set differently for an identical configuration,
>> and quite often satellite peaks may appear later in the time of use (aging
>> of the tube produces more W L, Fe filters may corrode and get
>> perforated...). So it is strictly recommended to check the instrument
>> peridically, by measuring a full pattern of a profile standard (LaB6 or Si
>> or similar).
>> Greetings
>> Reinhard
>>
>> Zitat von Habib Boughzala :
>>
>>
>> Dear all,
>> I would like to send you my witness related to this kind of observation.
>> I can assure that our Bruker D8 is clean and optimized!
>>
>> In many cases of well conditioned thin film (spin coating or controlled
>> diffusion) material this kind of phenomenon is visible around the highest
>> reflection, especially when the preferred orientation is drastically
>> present.
>>
>> So, in my opinion, Reinhard and Alan are right, and what is observed is
>> just like reflections broadening, asymmetry, shifting ...etc ... and can be
>> related to the material behavior.
>> Now, what is the physical (crystallographic!) property responsible of
>> this phenomenon? let's open the floor for a large discussion.
>>
>>
>> Habib
>>
>>
>> -- Message d'origine --
>> De "Alan W Hewat" 
>> À "Reinhard Kleeberg" 
>> Cc rietveld_l@ill.fr
>> Date 04/09/2023 09:29:08
>> Objet Re: [EXT] Re: [External] Re: Step-like basline
>>
>>
>> Reinhard is right that it is best to improve the instrument to produce
>> cleaner data. I'm concerned about the advice to model all kinds of features
>> whose origin is not fully understood, simply to obtain a better fit. Shay
>> has told us nothing about his instrument or his conditions of data
>> collection. He asks "Is it a sample preparation problem", to which the
>> obvious reply is "Do you see this with other samples or different
>> materials" ? Only he can answer that. If the answer is yes, he might try
>> modifying his instrument (remove filters etc) to see what effect that has
>> on the pattern from a simple well characterised material. Again only he can
>> do that. Data collection is an experimental science, and data refinement
>> should not be reduced to a "black box" computer program where extra
>> parameters can be added to reduce the R-factor.
>> Alan.
>>
>> On Mon, 4 Sept 2023 at 08:18, Reinhard Kleeberg <
>> kleeb...@mineral.tu-freiberg.de> wrote:
>>
>> Can be modeled in the BGMN peak profile model as well, by modifying
>> the *.lam file by a series of additional Lorentzians on the 1/lambda
>> scale, see figure.
>> The same can be done for other spectral impurities, e.g. W L
>> satellites. Also "electronic effects" on the wavelength distribution
>> profile like the "edges" from the ROI settings of Si drift detectors
>> can be modelled in such a convolution based approach.
>> However, better to have a pure/simple wavelength distribution (clear
>> alpha1/2 doublet) by a monochromator or high energy resolution
>> detector, as any satellites make trouble in trace phase analysis and
>> do cause prolonged calculation time in complicated Rietveld refinements.
>>
>> Reinhard
>>
>>
>>
>> Zitat von Matthew Rowles :
>>
>>
>> Topas can model them quite well. The functionality was introduced in
>> version 5.
>>
>> On Mon, 4 Sep 2023, 00:54 Kurt Leinenweber,  wrote:
>>
>>
>> Hi, Are these things modeled in Rietveld pr

RE: [EXT] [External] Re: Step-like basline

[Cline, James P. Dr. (Fed)]

Our favored configuration is a Johansson incident beam monochromator and a 
naked PSD.


James P. Cline
Materials Measurement Science Division
National Institute of Standards and Technology
100 Bureau Dr. stop 8370 [ B113 / Bldg 217 ]
Gaithersburg, MD 20899-8523USA
james.cl...@nist.gov
https://www.nist.gov/people/james-p-cline
(301) 975 5793

From: rietveld_l-requ...@ill.fr  On Behalf Of Luca 
Lutterotti
Sent: Monday, September 4, 2023 1:08 PM
To: rietveld_l@ill.fr
Cc: Habib Boughzala 
Subject: Re: [EXT] [External] Re: Step-like basline

Dear Habib,

Reinhard is right, and what he explained is exactly what you observed. Now I 
would add that I may not define your Bruker clean and optimised, because for 
this kind of samples, wafers and extremely textured thin films, it would be 
better to have a monochromator in the incident beam and not a Ni filtered (I 
would more say it is a requirement). It was already showed many times in the 
past as a monochromator in the incident beam is a necessity for this materials 
to avoid all the "physical artifacts" created by the strong intensity and not 
clean Kalpha radiation.

Best regards,

Luca

[cid:image001.png@01D9DF3B.30AEB200]

Luca Lutterotti
Dipartimento di Ingegneria Industriale
Università di Trento
via Sommarive, 9 - 38123 Trento (Italy)
tel. +39 0461 2824-14 (Office), -34 (X-Ray lab)

[cid:image002.png@01D9DF3B.30AEB200][cid:image003.png@01D9DF3B.30AEB200][cid:image004.png@01D9DF3B.30AEB200][cid:image005.png@01D9DF3B.30AEB200][cid:image006.png@01D9DF3B.30AEB200]

Maud: http://maud.radiographema.com




On 4 Sep 2023, at 12:20, Habib Boughzala 
mailto:habib.boughz...@ipein.rnu.tn>> wrote:

Many thanks Reinhard,

That's exactly what I wanted to say by  "I can assure that our Bruker D8 is 
clean and optimized!"
Otherwise, in some other cases of well conditioned thin film no similar 
phenomenon is observed!
So, yes, it's obviously possible that your point of view is right.

Regards
Habib


-- Message d'origine --
De "Reinhard Kleeberg" 
mailto:kleeb...@mineral.tu-freiberg.de>>
À "Habib Boughzala" mailto:boughz...@yahoo.com>>
Cc rietveld_l@ill.fr
Date 04/09/2023 11:07:50
Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline

Dear Habib,
the phenomenom "satellites or edges" originates from the diffraction process. 
The critical parameters are:
- spectral pureness of the primary beam (primary beam monochromator, tube 
spectral contamination like W...)
- the use of K beta absorbtion filter (and its thickness)
- the energy resolution ("window") of the detector system.
Even a D8 system may be equipped with different types of detectors, slits and 
energy limits can be set differently for an identical configuration, and quite 
often satellite peaks may appear later in the time of use (aging of the tube 
produces more W L, Fe filters may corrode and get perforated...). So it is 
strictly recommended to check the instrument peridically, by measuring a full 
pattern of a profile standard (LaB6 or Si or similar).
Greetings
Reinhard

Zitat von Habib Boughzala mailto:boughz...@yahoo.com>>:

Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or controlled 
diffusion) material this kind of phenomenon is visible around the highest 
reflection, especially when the preferred orientation is drastically present.

So, in my opinion, Reinhard and Alan are right, and what is observed is just 
like reflections broadening, asymmetry, shifting ...etc ... and can be related 
to the material behavior.
Now, what is the physical (crystallographic!) property responsible of this 
phenomenon? let's open the floor for a large discussion.


Habib


-- Message d'origine --
De "Alan W Hewat" 
mailto:alan.he...@neutronoptics.com>>
À "Reinhard Kleeberg" 
mailto:kleeb...@mineral.tu-freiberg.de>>
Cc rietveld_l@ill.fr
Date 04/09/2023 09:29:08
Objet Re: [EXT] Re: [External] Re: Step-like basline

Reinhard is right that it is best to improve the instrument to produce cleaner 
data. I'm concerned about the advice to model all kinds of features whose 
origin is not fully understood, simply to obtain a better fit. Shay has told us 
nothing about his instrument or his conditions of data collection. He asks "Is 
it a sample preparation problem", to which the obvious reply is "Do you see 
this with other samples or different materials" ? Only he can answer that. If 
the answer is yes, he might try modifying his instrument (remove filters etc) 
to see what effect that has on the pattern from a simple well characterised 
material. Again only he can do that. Data collection is an experimental 
science, and data refinement should not be reduced to a "black box" computer 
program where extra parameters can be added to reduce the R-factor.
Al

Re: [EXT] [External] Re: Step-like basline

[Reinhard Kleeberg]

Dear Luca,
I completely agree with your opinion, and want to add that even for  
"trivial" tasks in XRPD like phase analysis and standard Rietveld  
refinements the satellites/spectral impurities do cause significant  
trouble:


- The K beta and W L satellites of strong peaks of major phases like  
quartz, carbonates or cubic structures in geomaterials are typically  
not automatically recognized in the standard peak search procedures  
and therefore misinterpreted to be K alpha peaks and added to the peak  
list. I can't tell you how often I was asked from colleagues for  
explanation of such "unidentified peaks", and how much time people  
have spent for searching for explanation of such artefact lines.
- In Rietveld analysis our software must generate the peaks at least  
for the measured angular range. Depending on the method how the  
software is doing this, we run into problems with the satellites. If  
the software generates the reflections from the positions of K alpha  
peaks from the start lattice parameters and the (extended) upper  
measured angle, K beta satellites of K alpha peaks outside this  
angular range will maybe not generated and remain unfitted in the  
pattern. If the software generates the peaks depending on the shortest  
wavelength in the wavelength profile (more intelligent approach), the  
software must generate much more reflections (with maxima outside the  
measured angular range) and all these peaks must be calculated over an  
extremely broad angular range. In the case of low symmetry structures  
with big cells or disordered structures described by partial structure  
factors and the resulting extreme high numbers of peaks, the  
"extension effect" will cause significantly prolonged time for  
calculations, without any positive effect.


That's why I prefer to use instrumentation with better monochromatic  
radiation (monochromators, high energy resolution detectors) even in  
the daily business of phase analysis. We do use our 1D detector  
Mythen2 with Fe filter (Co radiation) only for "quick and dirty"  
measurements.


Best regards

Reinhard


Zitat von Luca Lutterotti :


Dear Habib,

Reinhard is right, and what he explained is exactly what you  
observed. Now I would add that I may not define your Bruker clean  
and optimised, because for this kind of samples, wafers and  
extremely textured thin films, it would be better to have a  
monochromator in the incident beam and not a Ni filtered (I would  
more say it is a requirement). It was already showed many times in  
the past as a monochromator in the incident beam is a necessity for  
this materials to avoid all the "physical artifacts" created by the  
strong intensity and not clean Kalpha radiation.


Best regards,

Luca

 

Luca Lutterotti
Dipartimento di Ingegneria Industriale
Università di Trento
via Sommarive, 9 - 38123 Trento (Italy)
tel. +39 0461 2824-14 (Office), -34 (X-Ray lab)




Maud: http://maud.radiographema.com 


On 4 Sep 2023, at 12:20, Habib Boughzala  
 wrote:


Many thanks Reinhard,

That's exactly what I wanted to say by  "I can assure that our  
Bruker D8 is clean and optimized!"
Otherwise, in some other cases of well conditioned thin film no  
similar phenomenon is observed!

So, yes, it's obviously possible that your point of view is right.

Regards
Habib


-- Message d'origine --
De "Reinhard Kleeberg" >

À "Habib Boughzala" mailto:boughz...@yahoo.com>>
Cc rietveld_l@ill.fr 
Date 04/09/2023 11:07:50
Objet Re: Re[2]: [EXT] Re: [External] Re: Step-like basline


Dear Habib,
the phenomenom "satellites or edges" originates from the  
diffraction process. The critical parameters are:
- spectral pureness of the primary beam (primary beam  
monochromator, tube spectral contamination like W...)

- the use of K beta absorbtion filter (and its thickness)
- the energy resolution ("window") of the detector system.
Even a D8 system may be equipped with different types of  
detectors, slits and energy limits can be set differently for an  
identical configuration, and quite often satellite peaks may  
appear later in the time of use (aging of the tube produces more W  
L, Fe filters may corrode and get perforated...). So it is  
strictly recommended to check the instrument peridically, by  
measuring a full pattern of a profile standard (LaB6 or Si or  
similar).

Greetings
Reinhard

Zitat von Habib Boughzala >:



Dear all,
I would like to send you my witness related to this kind of observation.
I can assure that our Bruker D8 is clean and optimized!

In many cases of well conditioned thin film (spin coating or  
controlled diffusion) material this kind of phenomenon is visible  
around the highest reflection, especially when the preferred  
orientation is drastically present.


So, in my opinion, Reinhard and Alan are right, and what is  
obse