Possibility of a spin-Peierls state in CuSiO3 from electronic structure theory -: art. no. 073104

Electronic structure calculations are presented for the well-known CuGeO3 and the recently discovered isostructural CuSiO3 compounds. The magnitude of the dispersion in chain direction is considerably smaller for CuSiO3, whereas the main interchain couplings are rather similar in both compounds. Starting from extended one-band, tight-binding models fitted to the band structures, the exchange integrals were estimated for both compounds in terms of a spatially anisotropic Heisenberg model. Remarkable, frustrating second-neighbor couplings are found both for intra- and interchain interactions. A magnetic moment of about 0.35 mu (B) is predicted for CuSiO3 in the Neel state.