Tight-Binding LMTO

A Brief Description

  • A real space scheme for a first principles calculation of electronic structures and total energies at fixed ionic configurations has been developed. The scheme is based on the combination of the tight binding linear muffin-tin orbital (TB LMTO) method and the Real Space Green's Function Technique. The scheme is entirely first principle where the tight binding LMTO orbitals are used as basis functions. In the self-consistent loop, the local density of states (LDOS) at a site is required. We have established the relationship between LDOS and the LowdinTransformation of the Green's function which is combined with Wu's method for inversion of a matrix [ Ref. S.Y. Wu, J.A. Cocks and C.S.Jayanthi, Anaccelerated inversion Algorithm using Resolvent matrix Method, Computer Physics communications,71, 125 (1992).] In the calculation of total energy, the full electron density is used to include the effect of non-spherical nature in the potential. We have shown how to relate the full electron density with the real space Green's function in a non-orthogonal TB LMTO representation where the single-center decomposition technique and Delley's method have been employed in the total energy calculation. Our TB LMTO scheme has been applied to the electronic structure calculations of Si and Ge clusters. Comparison of our results with experiments and pervious ab initio studies on clusters suggests that our Real Space TB-LMTO scheme is accurate, reliable, and efficient.

  • We use the real space Green's function method to calculate the electronic local density of states for atoms near a step on the Cu(110) surface. The calculation is done in real space with LMTO parameters. The results show that there are substantial charge redistributions among atoms in the top and bottom region of the step, indicating a strong dipole moment in the vicinity of the step.

Recent Publications in Tight-Binding LMTO

  1. Z-L Xie, K.S. Dy, and S.Y. Wu, The First Principles Real-Space TB-LMTO Calculation of Electronic Structure for Atomic Clusters, Phys. Rev. B55, 1748 (1997).
  2. Z-L Xie The First Principles Real-Space TB-LMTO Calculation of Electronic Structure for Atomic Clusters, Ph.D Thesis, University of Louisville.
  3. C-K. Yang, Y-C. Cheng, K.S. Dy, and S.Y. Wu, Self-Consistent Method for the Calculation of Surface Electronic Structure and its Application to Cu(110), Phys. Rev. B52, 10803 (1995).