Noncollinear spin density functional theory for spin-frustrated and spin-degenerate systems

We have implemented ab initio linear combinations of Gaussian-type orbital calculations with generalized localized spin density approximation (GLSDA) for a dimer of equilateral H-3 as a model of the noncollinear magnetic clus ters. It has been found that the GLSDA solution with the three-dimensional noncollinear spin structure is, contrary to prior band calculations by othe r groups, the ground state near the O-h conformation. Further computational results are compared to that of ab initio generalized Hartree-Fock. The di fference between them and the influence of the correlation correction were discussed. (C) 2001 John Wiley & Sons, Inc.