Cs2SiO3

1998-10-30 Thread Hongwu Xu 

Dear All:

Does anyone have structural information (space group, cell
parameters, atomic positions) of Cs2SiO3? The thermodynamic data for this
compound are available but I couldn't find any crystallographic info..

Thanks,
Hongwu Xu

zorite

1999-01-29 Thread Hongwu Xu 

Dear All,

Does anyone know where I can find the structural info. (space group,
atomic positions, etc.) for zorite- a sodium titanium aluminum silicate
hydrate? 

Thanks,
Hongwu 

Dept. of Chem. Eng.
& Mater. Sci.
UC-Davis
Davis, CA 95616

Ab Initio

1999-02-27 Thread Hongwu Xu 

Dear All,

Could someone out there recommend me several papers regarding ab initio
Rietveld refinement? I have a nanomaterial phase whose structure is
completely unknown and I would like to solve the structure using power
x-ray data. Can GSAS alone do this or will I need other softwares? Your
suggestions are greatly appreciated.

Hongwu

GSAS

1999-03-16 Thread Hongwu Xu 

Hello everyone,

I've just installed the GSAS on my Windows-NT PC, but when I tried to run
"expedt", I got an error message saying "C:GSAS\PG-GSAS.pif, invalid
program file name, please check you pif file". However, I did not find any
*.pif files coming with the program. Did anyone encounter this problem
before? Any idea of solving it?

Thanks,
Hongwu

Graphics

1999-03-30 Thread Hongwu Xu 

Hi, Everyone,

We have some neutron diffraction data collected and stored in the VAX
computer at Argonne, and we want to remotely get access to those data
from our Windows-PC or Mac here. However, we were unable to display the
diffraction patterns on our computers. Do we need an emulation program for
doing this? If yes, what are the possible programs, especially those that
could be downloaded from websites? Any suggestions will be apreciated.

Hongwu

Negative Biso

1999-05-14 Thread Hongwu Xu 

Dear All,

I'm currently doing refinement for a Cs-Zr-Si-O phase using GSAS. While
the refinement proceeded stably and the final cycle got converged, the
displacement factors (Biso) were negative except for Cs. I tried with two
sets of data collected on two diffractometers, and the situations are the
same. Could anyone out there expain to me what this means? Any suggestions
to solve this problem?

Many thanks,
Hongwu