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dschick / udkm1Dsim

A Python Simulation Toolkit for 1D Ultrafast Dynamics in Condensed Matter
http://udkm1dsim.readthedocs.io
MIT License
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Wrong math for Debye Waller Factor in x-Ray class #148

Open jpudell opened 11 months ago

jpudell commented 11 months ago

Wrong math in ref/trans factors for Debye Waller Factor: Units cell Class requires de_wal_fac in units of m^2. The math in get_atom_reflection/trasmission_factor, requires the unit of m instead of m^2. Also the comment section shows different equations as used in the function.

dschick commented 11 months ago

Hi @jpudell

many thanks for revising the code and math!

However, I think the code in the Xray class is correct, but the unit of the dbf in the UnitCell class should be changed from m² to m?

Could you also point explicitly to the difference between docstring and code equations? I might not see it after so long time

jpudell commented 11 months ago

Hi dschick,

both is possible. In the literature it is more common to use the < u >^2 for the Debye Waller instead of < u >. In the Matlab version < u >^2 is used, so I suggest to also use it here.

The doc string was correct for the < u > version. (I mixed up / and ...) and corrected it for the < u >^2 version.