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Hi,<br>
<br>
Welcome to XAFS and all the excitement, thrills and adventure that
implies!<br>
<br>
First, since you are new to the subject, I would strongly recommend
you take a course<br>
on XAFS. Many synchrotron facilities offer such - e.g. The APS/IIT
Summer school was held<br>
last July; the SSRL course was last August, and NSLS2 had theirs in
November. Any schools<br>
being held this year will likely also be announced on this iFeffit
mailing list.<br>
<br>
Some other resources for learning the basics can be found here:<br>
<a class="moz-txt-link-freetext" href="https://www.ixasportal.net/ixas/index.php?option=com_content&view=article&id=46&Itemid=136">https://www.ixasportal.net/ixas/index.php?option=com_content&view=article&id=46&Itemid=136</a><br>
Matt's introduction is a good place to start.<br>
<br>
For "dynamic XAFS" searches, you should consider "pump probe xafs"
or "time-resolved xafs"<br>
as search terms. Searching for pump probe xafs for me easily yielded
this article<br>
<a class="moz-txt-link-freetext" href="https://link.springer.com/chapter/10.1007/978-3-319-43866-5_9">https://link.springer.com/chapter/10.1007/978-3-319-43866-5_9</a><br>
<br>
As for simulation of XAFS, one program is FEFF, developed by the
Rehr Group at the University of Washington<br>
<a class="moz-txt-link-freetext" href="http://feff.phys.washington.edu/">http://feff.phys.washington.edu/</a><br>
FEFF9 (8, 7) requires a license and modest fee for academic use, and
is widely used for simulating both the <br>
near edge and extended fine structure. Bruce Ravel's Demeter suite
of programs for XAFS processing and analysis<br>
includes an earlier version (FEFF6). Demeter is free - mostly a
labour of love by Bruce, and he likes beer and maple syrup if you
happen to run into him at a conference.<br>
<br>
FDMNES (Yves Joly group, Institut Neel) is another program for
simulating the near-edge. I find it works<br>
quite well. It allows for tweaking of the starting electronic
configuration as well (with cautionary notes) that<br>
might be useful for simulating excited systems (I haven't checked
literature to see if anyone has done so).<br>
<br>
An additional program of note for fitting and simulation is GNXAS
(DiCicco group, U. Camerino) but I haven't<br>
used it myself.<br>
<br>
I am probably overlooking others, but these should get you going. I
strongly recommend you take a course<br>
on the basics before plunging into any of these.<br>
<br>
cheers,<br>
Robert<br>
<br>
<div class="moz-cite-prefix">On 2019-01-23 1:26 p.m., Hunter Allison
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAH6J0e_vk1n4viX8H5A4vX=SRL0e5NQHmSZGEQ43wVxBzpwo5Q@mail.gmail.com">
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I'm a graduate student at the University of
California, Irvine. Firstly, thank you for all the copious
resources. It is a treasure trove of information and a
beacon of light for someone just starting out. </div>
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Let's begin with some brief background. In my
research group, we intend to perform pump-probe
spectroscopy with attosecond x-ray probes. The Professor
says that we can use XAFS to study how the electrons move
on these very short timescales. While the system is being
setup and other experiments are being conducted, my
Professor wants me to figure out how to do simulations of
XAFS. This is a bit of a daunting order, since I've never
simulated anything before and only have basic programming
knowledge. The only direction I have is, "Try Google.".</div>
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So, today, I've been "trying Google" and found my way
to here. Since, I don't really know what I'm doing, I
thought I try asking and finding out if anyone else does
this sort of thing:</div>
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style="font:400 13.33px/19.99px
Arial,Helvetica,sans-serif;text-align:left;color:rgb(34,34,34);text-transform:none;text-indent:0px;letter-spacing:normal;text-decoration:none;word-spacing:0px;display:inline;white-space:normal;font-size-adjust:none;font-stretch:100%;float:none;background-color:transparent">How/where
does one do simulations of dynamic XAFS? Where would I
get started?</span></div>
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style="font:400 13.33px/19.99px
Arial,Helvetica,sans-serif;text-align:left;color:rgb(34,34,34);text-transform:none;text-indent:0px;letter-spacing:normal;text-decoration:none;word-spacing:0px;display:inline;white-space:normal;font-size-adjust:none;font-stretch:100%;float:none;background-color:transparent">(Please
forgive me if this question has been answered somewhere
else or if it seems profoundly dumb or too broad. I'm
really just looking for some more direction. Perhaps, it
could be that nobody does this and, in that case, I need
to figure out how to model this myself. Wow! That
thought seems daunting.)</span><br>
</div>
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For example, let's say I want to find out how the
x-ray adsorption of a carbon foil like Graphene would
change on attosecond time scales as it's heated by a
femtosecond laser and electrons move. Is there a program
or code out there that people use to model this sort of
thing?<br>
</div>
</div>
</div>
</div>
<br>
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