[answered] Is it possible to VCA

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somourad
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Joined: Thu Feb 18, 2010 11:18 am

[answered] Is it possible to VCA

Post by somourad » Fri Apr 15, 2011 11:59 am

Dear all,
I want to calculated elastic and vibrationall properties of sr s1-x ox alloys, I have not sure to using VCA for this compounds because high LO-TO spliting for SrS (100 cm-1) and SrO (260 cm-1) and high born effective charge, so I don’t know which condition for using VCA.
Thanks

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jzwanzig
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Re: Is it possible to VCA

Post by jzwanzig » Mon Apr 18, 2011 10:49 am

Chemically, sulfur and oxygen are not very similar so I see no reason why VCA would give good results in this system. But VCA is not a "rigorous theory" which means you should find a well-understood model system including S and O and test the approximation.
Josef W. Zwanziger
Professor, Department of Chemistry
Canada Research Chair in NMR Studies of Materials
Dalhousie University
Halifax, NS B3H 4J3 Canada
jzwanzig@gmail.com

somourad
Posts: 13
Joined: Thu Feb 18, 2010 11:18 am

Re: Is it possible to VCA

Post by somourad » Mon Apr 18, 2011 7:12 pm

Dear Prof:
Thank you very much for your help .

Best regards.

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