[Ifeffit] Coordination number

[Anatoly Frenkel]

These references may be useful as the answers to both "why" and "how".

http://pubweb.bnl.gov/users/frenkel/www/PTRU/ptru.pdf

http://pubweb.bnl.gov/users/frenkel/www/PTRU/evolution.pdf

By "average", do you mean average betwee the A-B and A-A first nearest
neighbor coordination numbers? They should not be averaged unless A and B
are similar elements, like Cu and Ni. If they have good Z-contrast, EXAFS
can count them separately, see refs above.

Anatoly


-----Original Message-----
From: ifeffit-bounces at millenia.cars.aps.anl.gov
[mailto:ifeffit-bounces at millenia.cars.aps.anl.gov]On Behalf Of Juan
Antonio Macia Agullo
Sent: Thursday, November 23, 2006 1:16 PM
To: XAFS Analysis using Ifeffit
Subject: [Ifeffit] Coordination number



Hi all,

I have a simple question but I am afraid it is polemic. Why people
always calculate coordination numbers and bond distances and how?
I have an e-mail where Bruce described perfectly how to calculate the
coordiantion number for the first shell. But,...if I have bimetallic
catalysts or/and a mixture of structures with several close paths
(similar Reff), then coordination number is an average number? I am not
very sure how to calculate them in Artemis with SO2 and standards.

Thank you very much

Best regards,
JA