Theoretical study on the geometry and the electronic structure of FeS2 (100) surface
FeS2(100)表面原子几何与电子结构的理论研究

The geometry and the electronic structure of FeS 2(100) surface is studied using the density functional theory(DFT)method.The(100)surface is very stable,does not give any significant geometric relaxation and can be regarded as simple termination of the bulk structure along a plane of cleaved Fe S bonds.The electronic structure at the (100)surface appears rather different from the bulk electronic structure.The electronic structure of FeS 2(100)surface is characterized by surface states in the forbidden zone.The highest occupied and the lowest unoccupied states are localized at surface Fe sites.According to ligand field theory,the existence of a new type of surface states in the forbidden zone resulting from symmetry reduction of the Fe coordination is deduced.