[Ifeffit] temperature dependency of amp parameter

[Matt Newville]

Hi Abdul,

On Mon, May 21, 2018 at 3:24 PM Abdul Ahad <matrixabdulahad at gmail.com>
wrote:

> Hi all,
> I have little confusion that do i fix or change S2 for each data set
> measured at different temperature. The compound is not monoatomic so i used
> Einstein model for sigma2. What about amplitude S2.
> ​'
>

​Generally speaking, S02 is independent of temperature, at least for a
system that is not changing state.  That is, S02 is essentially an atomic
property.  If you melt a material, you'll first change the coordination
number.  Eventually (say 10,000 K) you might get to the point where you're
moving electrons out of the atom, and in a plasma, S02 may not be the same
as for low temperatures.   But, when your sample is in a solid or liquid
state, S02 should not depend on temperature.

--Matt
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://millenia.cars.aps.anl.gov/pipermail/ifeffit/attachments/20180521/2b161942/attachment.html>