Methfessel M., Rodriguez C.O., Andersen O.K.
For fast and accurate density-functional calculations the authors devise a small basis set consisting of atom-centered linear muffin-tin orbitals (LMTOs). For the test case Si, an absolute total-energy convergence of 0.2 eV/atom is obtained with 22 LMTOs/atom. The calculated lattice constant, elastic constants, phonon frequencies, mode Gruneisen, and strain parameters, as well as the energy-volume curves for various crystalline phases are in accord with experimental data. This includes the 0.43-eV/atom energy difference between the diamond and BCC phases. Compared with pseudopotential plane-wave (PP-PW) calculations, the authors full-potential LMTO calculations are at least as accurate. In contrast with the PP-PW method, and in common with the linear augmented plane-wave method, the LMTO method can treat materials with atoms of any kind. By virtue of its 5-10 times smaller basis set, it is much faster.
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