[Ifeffit] Mixed Multiple scattering shell

Frenkel, Anatoly frenkel at bnl.gov
Wed Apr 1 13:03:36 CDT 2009

Could be helpful: RbBr, KBr, RbCl, AgBr(x)Cl(1-x) etc.l:
A. Frenkel, E. A. Stern, M. Qian, and M. Newville, 
Multiple - scattering x-ray-absorption fine-structure analysis and thermal expansion of alkali halides, 
Phys. Rev. B 48 , 12449 (1993). 

A. Frenkel, E. A. Stern, A. Voronel, M. Qian, and M. Newville, 
Buckled crystalline structure in mixed ionic salts, 
Phys. Rev. Lett., 71 , 3485 (1993).

A. Frenkel, E. A. Stern, A. Voronel, M. Qian, and M. Newville, 
Solving the structure of disordered mixed salts, 
Phys. Rev. B 49 , 11662 (1994). 
A. Frenkel, A. Voronel, A. Katzir, M. Newville, and E. A. Stern, 
Buckled crystalline structure of disordered mixed salts, 
Physica B 208 & 209 , 334 (1995).



From: ifeffit-bounces at millenia.cars.aps.anl.gov on behalf of Joseph Washington
Sent: Wed 4/1/2009 1:55 PM
To: XAFS Analysis using Ifeffit
Subject: [Ifeffit] Mixed Multiple scattering shell

Hello all,
I was wondering if anyone can send any useful hints or tips for parameterizing a mixed multiple scattering shell comprised of two NaCl type strucutres, like the AgBr(1-x)Cl(x) example. Has anyone worked on fitting the third shell in that example? I am looking for examples of nacl rocksalt-like FEFF calculations that have successfully parametrized multiple scattering path contributions. Right now, after running feff, I'm using a different delr / ss term for each multiple scattering path I include. Does anyone have any clever ways of representing these in terms of the delr/ss in the first shell? Also, FEFF is telling me that the amp and mixing terms are almost completely correlated and this cause the amp term to blow up. 
Thanks all, I really appreciate the assistance!

-------------- next part --------------
A non-text attachment was scrubbed...
Name: winmail.dat
Type: application/ms-tnef
Size: 4698 bytes
Desc: not available
URL: <http://millenia.cars.aps.anl.gov/pipermail/ifeffit/attachments/20090401/fd67ddf9/attachment.bin>

More information about the Ifeffit mailing list