One can also use:

$ gemmi fprime Sr --wavelength=1.2782
Element     E[eV]    Wavelength[A]       f'         f"
Sr    9699.91     1.2782     -0.63756    1.3067

or

$ $CCP4/lib/py2/cctbx/bin/cctbx.eltbx.show_fp_fdp --wavelength=1.2782
--elements=Sr
Wavelength: 1.2782 Angstrom

Element: Sr
  Henke et al.  : f'=-0.665752, f''=1.332521
  Sasaki et al. : f'=-0.75942 , f''=1.306888
  diff f''=-0.97 %

As you see, all these commands give slightly different values. I was
told that nowadays XrayDB (not in CCP4) provides the most accurate
values:

$ python3 -c "import xraydb; print(xraydb.f1_chantler('Sr', 9699.91))"
-0.657390314908364

Crossec is the original code from Don Cromer. Gemmi, one of the cctbx
tables, and I think Ethan's server also use code that stems from it,
but with corrections added later when this code was circulating, such
as Kissel & Pratt, Acta Cryst. A46, 170 (1990).

Marcin

On Fri, 22 Jan 2021 at 21:40, Mitchell D. Miller
<mitchell.d.mil...@rice.edu> wrote:
>
> You can also use the ccp4 legacy program crossec ---
> http://legacy.ccp4.ac.uk/html/crossec.html
>
> for your case --
>
> echo -e "NWAV 1 1.2782\nATOM Sr\nEND\n" | crossec | grep SR
>
>    Atom symbol and number SR       38
>   $TABLE:Wave length v F' and F"-  SR   :
>   $GRAPHS:Lambda v F' and F" SR   :A:2,3,4: $$
> SR          1.2782    -0.7663     1.3068
>
>
> I often ran it from a script to lookup the f'/f" for various elements via
> a script crossec.sh which takes arguments of wavelength followed by a
> list of elements
>
> #!/bin/bash
> #egrep '^ATOM|^HETATM' | cut -c77-78 file.pdb | sort -u`
>
> for atom in "$@"
>    do
>     if [ "$atom" != "$1" ]
>       then
>         echo -e "NWAV 1 $1\nATOM $atom\nEND\n" | crossec | awk '/^
> Lambda  F/ {getline ; getline ; print $0}'
>       else
>        echo "Atom_type   Lambda     F"\'"         F"\"
>     fi
> done
>
>
>
> Quoting Bernhard Rupp <hofkristall...@gmail.com>:
>
> > ...or you can use the old anoweb app
> >
> > http://www.ruppweb.org/new_comp/anomalous_scattering.htm
> >
> >
> >
> > http://www.ruppweb.org/cgi-bin/anoweb_linux?Element=Sr
> > <http://www.ruppweb.org/cgi-bin/anoweb_linux?Element=Sr&iano=1&nresi=100&iwavl=K&w1=Cu&w2=1000&w3=2&w4=1&w5=700&anoweb=Submit>
> > &iano=1&nresi=100&iwavl=K&w1=Cu&w2=1000&w3=2&w4=1&w5=700&anoweb=Submit
> >
> >
> >
> > HTH, BR
> >
> > From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> On Behalf Of rohit kumar
> > Sent: Friday, January 22, 2021 11:36
> > To: CCP4BB@JISCMAIL.AC.UK
> > Subject: [ccp4bb] (scattering factors) f and f" for Sr Heavy atom
> >
> >
> >
> > Hello All,
> >
> >
> >
> > I have data collected at Wavelength: 1.2782 (For Sr Heavy atom) with
> > a resolution of 1.6 A. I was trying to run Crank in ccp4 for SAD
> > phasing and It  asks me to fill the values of (scattering factors) f
> > and f" for the heavy atom.
> >
> > Can anyone please help with this, how to calculate or where to find
> > these f and f" values for Sr heavy atoms?
> >
> >
> >
> > Please let me If you need any information from my side.
> >
> >
> >
> > Thank you in advance
> >
> >
> >
> >
> >
> >
> > --
> >
> > Regards
> > Dr. Rohit Kumar Singh
> >
> > Postdoctoral fellow
> >
> >
> >
> >
> >
> >
> >
> >   _____
> >
> > To unsubscribe from the CCP4BB list, click the following link:
> > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB
> > <https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1>
> > &A=1
> >
> >
> > ########################################################################
> >
> > To unsubscribe from the CCP4BB list, click the following link:
> > https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1
> >
> > This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a
> > mailing list hosted by www.jiscmail.ac.uk, terms & conditions are
> > available at https://www.jiscmail.ac.uk/policyandsecurity/
>
> ########################################################################
>
> To unsubscribe from the CCP4BB list, click the following link:
> https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1
>
> This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing 
> list hosted by www.jiscmail.ac.uk, terms & conditions are available at 
> https://www.jiscmail.ac.uk/policyandsecurity/

########################################################################

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1

This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list 
hosted by www.jiscmail.ac.uk, terms & conditions are available at 
https://www.jiscmail.ac.uk/policyandsecurity/

Reply via email to