Ab initio evaluation of local effective interactions in alpha '-NaV2O5 | |
Article | |
关键词: SPIN-PEIERLS COMPOUND; ABINITIO DIRECT CALCULATION; COMPLETE ACTIVE SPACE; CONFIGURATION-INTERACTION; STRUCTURAL-PROPERTIES; ELECTRONIC-STRUCTURE; ENERGY DIFFERENCES; LADDER COMPOUND; X-RAY; TRANSITION; | |
DOI : 10.1103/PhysRevB.62.402 | |
来源: SCIE |
【 摘 要 】
We will present the numerical evaluation of the hopping and magnetic exchange integrals for a nearest-neighbor t-J model of the quarter-filled alpha'-NaV2O5 compound. The effective integrals are obtained from valence-spectroscopy ab initio calculations of embedded crystal fragments (two VO5 pyramids in the different geometries corresponding to the desired parameters). We are using a large configurations interaction (CI) method, where the CI space is specifically optimized to obtain accurate energy differences. We show that the alpha'-NaV2O5 system can be seen as a two-dimensional asymmetric triangular Heisenberg lattice where the effective sites represent delocalized V-O-V rung entities supporting the magnetic electrons.
【 授权许可】
Free