Weyrich K.H., Brey L., Christensen N.E.
The optical-phonon frequencies in compound semiconductors are obtained from total-energy calculations using the local-density approximation in conjunction with a newly developed full-potential version of the linear-muffin-tin-orbital (LMTO) method. In this scheme the full nonsphericity of the potential is included throughout the self-consistency cycle. The results agree well with experiments and with the results of first-principles pseudopotential calculations. A linear correlation is found between the force constants and the sp3 bond orders as obtained, for instance, from conventional LMTO calculations for the undistorted crystals. This allows one to derive the optical-phonon frequencies for all zinc-blende-type semiconductors from those of only two materials, e.g. Si and Ge.
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