Re: [Ifeffit] Case of nonequivalent multiple atomic sites of absorbing atoms

2010-07-29 Thread Jatinkumar Rana
To: XAFS Analysis using Ifeffitifeffit@millenia.cars.aps.anl.gov Subject: Re: [Ifeffit] Case of nonequivalent multiple atomic sites of absorbing atoms Message-ID: aanlktikm-ufmhua8tpoq3ja7xr0bc+xxfpwfsh75r...@mail.gmail.com Content-Type: text/plain; charset=ISO-8859-1 Dear Rana, Delta

[Ifeffit] Case of nonequivalent multiple atomic sites of absorbing atoms

2010-07-28 Thread Jatinkumar Rana
Dear Users, Since long, i was trying to understand the physical meaning of term Delta E0 and S02 in EXAFS equation. I have little bit of idea about both of them. for example, S02 is element specific and it is transferable between samples (if we consider same absorbing atom). However, I am

Re: [Ifeffit] Case of nonequivalent multiple atomic sites of absorbing atoms

2010-07-28 Thread Matt Newville
Dear Rana, Delta E0 is a shift in the Energy origin of k, that is where k=0. For the experimental data, this was chosen empirically (and so somewhat arbitrarily) from the measured data. For the FEFF calculation, it was chosen at the calculated absorption threshold (lowest available electronic

Re: [Ifeffit] Case of nonequivalent multiple atomic sites of absorbing atoms

2010-07-28 Thread Scott Calvin
Hi Rana, Currently, S02 is usually described as being due to the relaxation of the other electrons in an atom when a core electron is removed, resulting in incomplete overlap of initial and final states. This appears to be a fairly good description, as careful experiments show good