Ab initio research on third-order nonlinear optical properties of linear complexes [M(I)(PH3)2]+(M=Cu, Ag, Au)

Geometry of linear complexes [M(I)(PH3)(2)](+) (M=Cu, Ag, Au) were optimized at different basis set levels adopting ab initio HF and DFT methods of quantum chemistry. The third-order NLO coefficients gamma were calculated with FF/HF method. The values gamma of [M(I)(PH3)(2)](+) (M=Cu, Ag, Au) are 10596.6538, 14649.9410 and 11190.8090a.u. respectively with the basis set of 6-31+G(d) for P and H and the basis set of LANL2DZ for Au by ab initio HF method. The results show the rule of gamma([Ag(I)PH3)2])>gamma([Au(I)(PH3)2]+)>gamma([Cu(I)(PH3)2])(-) at the different basis set levels.