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<div>Dear FEFF users!</div>
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<div>I am looking into the use of the DEBYE card in order to calculate the EELS spectrum of graphite at ~800 K. Obviously, graphite is highly anisotropic, such that it would be unphysical to use a single Debye temperature. However, the effective in-plane (a,b
axes) and out-of-plane (c axis) Debye temperatures are known for graphite (2500 and 950 K, respectively). I was therefore wondering whether it is possible in FEFF9 to specify two Debye temperatures for the two different crystallographic directions.</div>
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<div>I am calculating the (oriented) EELS spectrum of graphite in reciprocal space using the RECIPROCAL, LATTICE and ATOMS cards; see feff.inp file below. I am using FEFF version 9.05.</div>
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<div>In case the use of Debye temperatures is not possible in this way, could anybody recommend another way to take into account the Debye-Waller factors for an anisotropic material such as graphite?</div>
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<div>Thanks!</div>
<div>Best regards,</div>
<div>Renske van der Veen</div>
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<div>-- </div>
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<div>Dr. Renske M. van der Veen</div>
<div>California Institute of Technology</div>
<div>Arthur Amos Noyes Laboratory of Chemical Physics</div>
<div>1200 E California Blvd</div>
<div>MC 127-72, Pasadena, CA 91125, USA</div>
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<div>Office: (+1) (626) 395 6530</div>
<div>Mobile: (+1) (626) 808 2635</div>
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<div>****</div>
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<div> TITLE graphite</div>
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<div>* C K edge energy = 284.20 eV</div>
<div> EDGE K 0.0</div>
<div> CONTROL 1 1 1 1 1 1</div>
<div> PRINT 1 1 1 1 1 1 </div>
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<div>COREHOLE RPA</div>
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<div>LDOS -20 10 0.05 * this calculates the density of states</div>
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<div>EGRID </div>
<div>e_grid -3 17 0.3</div>
<div>e_grid last 30 0.4</div>
<div>e_grid last 58 1</div>
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<div>ELNES </div>
<div>200 # beam energy in keV</div>
<div>0 0 1 # beam direction in the crystal frame</div>
<div>10 5 # collection semiangle, convergence semiangle (in mrad)</div>
<div>200 1 # q-integration mesh : radial size, angular size</div>
<div>0.0 0.0 # position of the detector (x,y angle in mrad)</div>
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<div> FMS 7.0 2</div>
<div> EXCHANGE 0 1 0.7</div>
<div> SCF 5</div>
<div> RPATH 0.2</div>
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<div> POTENTIALS</div>
<div> * ipot Z element l_scmt l_fms stoichiometry</div>
<div> 0 6 C 3 2 0.01</div>
<div> 1 6 C 3 2 2</div>
<div> 2 6 C 3 2 2</div>
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<div> RECIPROCAL</div>
<div> KMESH 5000</div>
<div> MARKER 1</div>
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<div> LATTICE P 2.4612</div>
<div> 0.86603 -0.50000 0.00000</div>
<div> 0.00000 1.00000 0.00000</div>
<div> 0.00000 0.00000 2.72546</div>
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<div> ATOMS * this list contains 251 atoms</div>
<div>* * x y z ipot tag distance</div>
<div> 0.00000 0.00000 0.68160 1 C1</div>
<div> 0.00000 0.00000 2.04479 1 C1</div>
<div> 0.57735 0.00000 0.68160 2 C2</div>
<div> 0.28868 0.50000 2.04479 2 C2</div>
<div> END</div>
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