Parallel, linear-scaling building-block and embedding method based on localized orbitals and orbital-specific basis sets
Abstract
We present a new linear scaling method for the energy minimization step of semiempirical and first-principles Hartree-Fock and Kohn-Sham calculations. It is based on the self-consistent calculation of the optimum localized orbitals of any localization method of choice and on the use of orbital-specific basis sets. The full set of localized orbitals of a large molecule is seen as an orbital mosaic where each tessera is made of only a few of them. The orbital tesserae are computed out of a set of embedded cluster pseudoeigenvalue coupled equations which are solved in a building-block self-consistent fashion. In each iteration, the embedded cluster equations are solved independently of each other and, as a result, the method is parallel at a high level of the calculation. In addition to full system calculations, the method enables to perform simpler, much less demanding embedded cluster calculations, where only a fraction of the localized molecular orbitals are variational while the rest are frozen, taking advantage of the transferability of the localized orbitals of a given localization method between similar molecules. Monitoring single point energy calculations of large poly(ethylene oxide) molecules and three dimensional carbon monoxide clusters using an extended Huckel Hamiltonian are presented.
Cite
@article{arxiv.cond-mat/0407336,
title = {Parallel, linear-scaling building-block and embedding method based on localized orbitals and orbital-specific basis sets},
author = {Luis Seijo and Zoila Barandiaran},
journal= {arXiv preprint arXiv:cond-mat/0407336},
year = {2009}
}
Comments
latex, 15 pages, 10 figures, accepted for publication in J.Chem.Phys