>
> I am working with the Koalariet software. I have presented problems upon
> loading an experimental data from a sample (Silicon) with which the
> diffractometer was calibrated. Xfit Koalariet display the pattern of this
> sample in screen but with all displaced picks; when I analyze statements
> values I find that they correspond to a wavelength which was not used in
> the mensurements (my pattern was fact with KaCu, Xfit shows the pattern
> for a KaCo).
> Somebody is able to help me with this apparent problem. Is
> maybe that does it have any wavelength introduced by default?, if being
> so, where could be changed?. I could say, also, that I have processed
> other patterns taken from Xfit in the same diffractometer and I have not
> this problem before.
>
For the wavelength in Koalariet, do you have something
like COKA3 instead of a CUKA? macro in your input file?
You can find out what generic wagelength types are in
the std.inp file - and you want to check the Macro
you are using has not been modified to a Cobalt wavelength.
You can also make up your own of
course. Can you email the header of your Koalariet
input file as per the example given below?
---
Re: Koalariet and Automatic Divergence Slit data:
Not done much with Koalariet with Automatic Divergence
Slits (as per previous discussion on the list, there is
(was?) an impression they are a bit suspect compared to
fixed slit setups for Rietveld quality work?) but for
fixed slits Koalariet does seem on the ball with the Fundamental
Parameters approach. You will notice for the following,
with this Y2O3 dataset, refining the receiving slit
and Sollers Slit angle, they both go near the "official"
values. (These are the two pieces that are routinely inserted
and removed depending on the type of data collection)
On the rare occassions I have looked at Automatic Divergence
Slit data with Koalariet, the impression was the ADS
was not setup and aligned correctly. Not sure about
other brands but the old Philips ADS (compared to the fixed
slit assembly) was not easy or fun to setup and align.
It would be interesting to compare this with BGMN.
The BGMN webpage implies it can handle a very wide
range of geometries. I believe the publically
available Koalariet is limited to Bragg Bretano
Laboratory diffractometer geometry.
http://www.bgmn.de/ger.html
UK Mirror:
http://www.ccp14.ac.uk/ccp/web-mirrors/bgmn/ger.html
Australian Mirror:
ftp://ftp.minerals.csiro.au/pub/xtallography/ccp14/ccp/web-mirrors/bgmn/ger.html
(As a reminder: refer to the notes if using R -3
with Koalariet as there is a workaround with this
spacegroup not doing the the right thing)
Lachlan.
PS: In the following case on a Philips 1710 system,
the Receiving slit was officially an 0.2mm slit,
the Soller Slit, 5.1 degrees acceptance angle.
/*
Become familiar with the files
std.inp
*/
' --------------------------------------
' The std.inp file contains standard macros
include "\koalarie\std.inp"
' --------------------------------------
' global_do_errors
global_r_wp 5.502
global_r_exp 2.757
global_iters 20
' --------------------------------------
xdd c:\koalarie\examples\y2o3.xdd c:\koalarie\examples\y2o3.cal
xdd_r_wp 5.502
CUKA5
LP_FACTOR(!lpfactor, 17)
xdd_diffractometer_radius 173
xdd_length_of_tube_filament 12
xdd_sample_length 15
xdd_receiving_slit_length 12
xdd_receiving_slit_width @ 0.1991
xdd_primary_soller_angle 5
xdd_secondary_soller_angle @ 4.492
xdd_divergence_fixed_angle 1
xdd_bkg @ 19.2803 99.1161 -21.6995 9.7390
ONE_ON_X(one_on_x, 7046.40139) ' a background function
ZERO_ERROR(ze1, 0.01752)
STR(I_a_-3) ' Y2O3
CUBIC(lp 10.60392)
site Y x -0.03234 y 0 z 0.25 occ Y+3 1 beq 0.4079 num_posns
24
site Y x 0.25 y 0.25 z 0.25 occ Y+3 1 beq 0.4724 num_posns
8
site O x 0.39101 y 0.15193 z 0.38107 occ O-2 1 beq 0.8148 num_posns
48
scale @ 0.0001555685
CS(cs1, 3142.33512)
MS(ms2, 0.00010)
--
Lachlan M. D. Cranswick
4th Jan - 16th March 1999 Visiting Scientist
CSIRO Division of Minerals, Melbourne, Australia
Tel: (613) 9545 8500 (switch)
Fax: (613) 9562 8919 [EMAIL PROTECTED]
Collaborative Computational Project No 14 (CCP14)
for Single Crystal and Powder Diffraction
Daresbury Laboratory, Warrington, WA4 4AD U.K
Tel: +44-1925-603703 Fax: +44-1925-603124
E-mail: [EMAIL PROTECTED] Ext: 3703 Room C14
NEW CCP14 Web Domain (Under heavy construction):
http://www.ccp14.ac.uk
