It would be helpful if I finished my own sentences. As an aside for those
who feel that capillary mounting is a lost art among the newer generation I
assure you it isn't. All you need is a busted cryo system and a crystal
backlog to get past the intimidation factor.

Katherine

On Wed, Jun 6, 2012 at 2:34 PM, Jacob Keller <j-kell...@fsm.northwestern.edu
> wrote:

> But the edges for I and Hg are pretty far from CuKa (see attached). I
> am familiar with their being extra signal (white lines) very close to
> the peak, but not so far away....
>
> JPK
>
>
>
> On Wed, Jun 6, 2012 at 2:15 PM, Bernhard Rupp (Hofkristallrat a.D.)
> <hofkristall...@gmail.com> wrote:
> > There is also a relevant point from the physics of the absorption
> spectra -
> > the XANES white lines (near edge peaks higher than the continuum
> transition
> > or edge step) depend on the chemical environment of the anomalous atom in
> > terms of available unoccupied states (which n. b. is something entirely
> > different that the local neighbor environment/geometry which can be
> > backtransformed - although with quite some uncertainty - from the EXAFS
> > wiggles).
> >
> > Any argument about absolute f" peak values in absence of experimental
> > evidence (scan) might want to consider that.....
> >
> > Best, BR
> >
> > -----Original Message-----
> > From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of
> Jacob
> > Keller
> > Sent: Wednesday, June 06, 2012 11:30 AM
> > To: CCP4BB@JISCMAIL.AC.UK
> > Subject: Re: [ccp4bb] Fun Question - Is multiple isomorphous replacement
> an
> > obsolete technique?
> >
> > No offense taken (we all have our dour moments!), but grant me a sincere
> > question: the f" occupancy value would have been just as close at 11 as
> 5 if
> > the true value were 8, am I correct? In other words, do you imply by
> saying
> > "doing well" that you got as *much* as 5, or that you got as *close* as
> 5? I
> > am just trying to see whether I understand these things correctly.
> >
> > Jacob
> >
> >
> >
> > On Wed, Jun 6, 2012 at 12:21 PM, Gerard Bricogne <g...@globalphasing.com
> >
> > wrote:
> >> Dear Jacob and all,
> >>
> >>     I realise that my last statement sounds awfully dour and
> >> dismissive, in a way I really didn't intend. Especially as Stefan's
> >> original posting was a "Fun Question".
> >>
> >>     Apologies to all for this over-the-top statement. I enjoyed a lot
> >> of the replies.
> >>
> >>
> >>     With best wishes,
> >>
> >>          Gerard.
> >>
> >> --
> >> On Wed, Jun 06, 2012 at 06:09:33PM +0100, Gerard Bricogne wrote:
> >>> Dear Jacob,
> >>>
> >>>      I thought that getting 5 for each iodine was doing pretty well,
> >>> given the circumstances - e.g. the noisy measurements, the primitive
> >>> software running on slow computers with tiny amounts of memory, etc. .
> >>>
> >>>      In any case my main point, directed at the original poster, was
> >>> that reading the early Acta Cryst. issues ("RTFL") might be an
> >>> alternative and perhaps more enlightening way of getting a picture of
> >>> the evolution of phasing methods than finding some clever filter
> settings
> > in the RCSB ;-) .
> >>>
> >>>
> >>>      With best wishes,
> >>>
> >>>           Gerard.
> >>>
> >>> --
> >>> On Wed, Jun 06, 2012 at 11:08:37AM -0500, Jacob Keller wrote:
> >>> > ...Even with such primitive techniques, I can remember an HgI4
> >>> > > derivative in which you could safely refine the "anomalous
> > occupancies"
> >>> > > (i.e. f" values) for the iodine atoms of the beautiful planar
> >>> > > HgI3 anion to
> >>> > > 5 electrons.
> >>> >
> >>> > I am surprised--f"'s of I and Hg are supposed to be around 8 for
> >>> > CuKa (or maybe you weren't using CuKa)?
> >>> >
> >>> > JPK
> >>> >
> >>> >
> >>> > --
> >>> > *******************************************
> >>> > Jacob Pearson Keller
> >>> > Northwestern University
> >>> > Medical Scientist Training Program
> >>> > email: j-kell...@northwestern.edu
> >>> > *******************************************
> >>
> >> --
> >>
> >>     ===============================================================
> >>     *                                                             *
> >>     * Gerard Bricogne                     g...@globalphasing.com  *
> >>     *                                                             *
> >>     * Global Phasing Ltd.                                         *
> >>     * Sheraton House, Castle Park         Tel: +44-(0)1223-353033 *
> >>     * Cambridge CB3 0AX, UK               Fax: +44-(0)1223-366889 *
> >>     *                                                             *
> >>     ===============================================================
> >
> >
> >
> > --
> > *******************************************
> > Jacob Pearson Keller
> > Northwestern University
> > Medical Scientist Training Program
> > email: j-kell...@northwestern.edu
> > *******************************************
> >
>
>
>
> --
> *******************************************
> Jacob Pearson Keller
> Northwestern University
> Medical Scientist Training Program
> email: j-kell...@northwestern.edu
> *******************************************
>

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