2009-12-16 04:06:01 +08:00
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# CdTe Stillinger-Weber potential: Z. Q. Wang, D. Stroud,
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# and A. J. Markworth, Phys. Rev. B, 40, 3129(1989).
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# The Stillinger-Weber parameters given in the literature are pair
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# specific. While most of the parameters are indeed pairwise parameters
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# according to their definition, the parameters epsilon and lambda
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# should be viewed as three-body dependent. Here we assume that the
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# the three-body epsilon and lambda is a geometric mean of the pairwise
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# epsilon and lambda.
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# In lammps, the parameters for the ij pair are entered in
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# the ijj three-body line. There is no unique way to convert pair
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# parameters to three body parameters so the example here represents
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# only one way. The three-body parameters epsilon_ijk can be calculated
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# from the literature pair parameters using epsilon_ijk =
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# sqrt(lambda_ij*epsilon_ij*lambda_ik*epsilon_ik)/lambda_ik, and the
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# results are directly entered in this table. Obviously, this
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# conversion does not change the two-body parameters epsilon_ijj.
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# All other ik pair parameters are entered on the i*k line, where *
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# can be any species. This is consistent with the requirement of
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# the ik parameter being on the ikk line.
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# These entries are in LAMMPS "metal" units: epsilon = eV;
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# sigma = Angstroms; other quantities are unitless
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# epsilon sigma a lambda gamma cos(theta) A B p q tol
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Cd Cd Cd 1.03 2.51 1.80 25.0 1.20 -0.333333333333 5.1726 0.8807 4.0 0.0 0.0
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Te Te Te 1.03 2.51 1.80 25.0 1.20 -0.333333333333 8.1415 0.6671 4.0 0.0 0.0
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Cd Cd Te 1.03 2.51 1.80 25.0 1.20 -0.333333333333 7.0496 0.6022 4.0 0.0 0.0
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Cd Te Te 1.03 2.51 1.80 25.0 1.20 -0.333333333333 7.0496 0.6022 4.0 0.0 0.0
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Te Cd Cd 1.03 2.51 1.80 25.0 1.20 -0.333333333333 7.0496 0.6022 4.0 0.0 0.0
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Te Cd Te 1.03 2.51 1.80 25.0 1.20 -0.333333333333 8.1415 0.6671 4.0 0.0 0.0
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Te Te Cd 1.03 2.51 1.80 25.0 1.20 -0.333333333333 7.0496 0.6022 4.0 0.0 0.0
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Cd Te Cd 1.03 2.51 1.80 25.0 1.20 -0.333333333333 5.1726 0.8807 4.0 0.0 0.0
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