Re: LaAlO3 structure
Joerg, At 07:07 AM 3/7/01 +, you wrote: snip We have done some investigations on the old line standard LaB6 SRM660, it contains some minor phases (sum 5%), one was LaAlO3. The new standard SRM660a is clean and has some other advantages, too. Now, we favour SRM660a over Y2O3. This is a pleasant report to hear! Will I see you at Accuracy in Powder Diffraction III? Best regards, Jim James P. Cline [EMAIL PROTECTED] Ceramics Division Voice (301) 975 5793 National Institute of Standards and Technology FAX (301) 975 5334 100 Bureau Dr. stop 8523 Gaithersburg, MD 20899-8523USA
New GSAS
Hi everyone, New versions of GSAS for MS-DOS/Winxx and Linux have been placed on the ftp site ftp://ftp.lanl.gov/public. A new copy of the GSAS Manual has also been placed there. The changes are in the latest GSAS News and are: 1. Each powder histogram may now have a weight factor. By default the value is 1.0; it can be changed in the histogram editing menu after which POWPREF must be run to implement it. This can be used to change the relative weighting of different powder histograms or to "shift" a high chi**2. Caution is advised in using this option. 2. The number of terms in each atom constraint is now 500; it was 100. This has not been explicitly tested but should work. 3. An error in lattice parameter constraints has been fixed. 4. The maximum size of Fourier maps is 5M elements. The size of a section is now arbitrary; this limit used to be 23000 imposed in FORPLOT. 5. An attempt has been made to fix a bug in the twin calculation routine. The old one only seemed to work for neutron magnetic structures. It should be noted that refinement of a "Flack" parameter can be done with the twin option by entering a twin element with the inversion matrix. 6. RAWPLOT now has an option to output the fitted profile appended after the peak fitting results. 7. The torsion angle restraint has been changed to have pseudopotential representation for the angle. 8. The output of several restraints have been changed to be more consistent with each other. I'm working on preparing a new SGI version as well. Bob Von Dreele
Powder patterns from single crystal intensity data
Hi everyone, I am wondering whether there is an easy to use tool that will take a SHELX format intensity file and instrumental parameters (or even without these) and calculate a powder pattern out of that. I know that sometime ago someone asked exactly the question I am now asking, but if I recall correctly the answer involved using Koalariet, which is a program with which I am not conversant. Thanks, AlexY Dr. Alexandre F. T. Yokochi Assistant Professor (Senior Research) Director, X-ray Crystallographic Facilities Department of Chemistry Oregon State University Corvallis, OR 97331-4003 Ph# (541) 737-6724 Email: [EMAIL PROTECTED] Fax# (541) 737-2062 Web Page: crystal.chem.orst.edu/~alexy (temporarily unavailable)
YBa2Cu3O7-y
I am looking for unit cell data of YBa2Cu3O7-y obtained from diffraction from a single crystal. The lattice parameters given in JCPDS records are obtained from powder diffraction. Could anyone help me? -Nagesh S.Kini Materials Research Centre Indian Institute of Science Bangalore - 560 012 --
Re: Re: Powder patterns from single crystal intensity data
Hi Alex, Try Oscail 8 ( controling program for both ortex and oscailp)and to call powutil and powdis( I used the stand alone oscailp before.) The output .ing is in xy format you can easy port to other display program or you can just use the powdis. http://ccp14.sims.nrc.ca/ccp/web-mirrors/ortex/cryst/index.htm Sean X. Ouyang Department of Chemistry Texas AM Univesity From: Lachlan Cranswick [EMAIL PROTECTED] Date: Mon, 12 Mar 2001 22:25:47 +1100 To: [EMAIL PROTECTED] Subject: Re: Powder patterns from single crystal intensity data I am wondering whether there is an easy to use tool that will take a SHELX format intensity file and instrumental parameters (or even without these) and calculate a powder pattern out of that. I know that sometime ago someone asked exactly the question I am now asking, but if I recall correctly the answer involved using Koalariet, which is a program with which I am not conversant. Thanks, AlexY Dr. Alexandre F. T. Yokochi Assistant Professor (Senior Research) Director, X-ray Crystallographic Facilities Department of Chemistry Oregon State University Corvallis, OR 97331-4003 Ph# (541) 737-6724 Email: [EMAIL PROTECTED] Fax# (541) 737-2062 Web Page: crystal.chem.orst.edu/~alexy (temporarily unavailable) Could any responses on this be posted to the list as I would be interested in hearing of such a program if it exists. While most of the single crystal suites will generate a powder pattern from a Shelx INS structure file (Platon/System S, ORTEX and WinGX); as far as I can tell, they will not generate pseudo-powder patterns from HKL intensity lists. More effort seems to have gone the other way in creating Pawley and Le Bail methods. Doing this type of thing properly from Shelx HKL data in Koalariet would not be that much fun(?). Lachlan. Lachlan M. D. Cranswick Geosciences - Lamont-Doherty Earth Observatory, Columbia University PO Box 1000, 61 Route 9W Palisades, New York 10964-1000 USA Tel: (845) 359-8302 Fax: (845) 365-8155 E-mail: [EMAIL PROTECTED] WWW: a href="http://www.ldeo.columbia.edu"http://www.ldeo.columbia.edu/a CCP14 Xtal Software Website: a href="http://www.ccp14.ac.uk"http://www.ccp14.ac.uk/a
