DFT study on second-order nonlinear optical properties of a series of 12-vertex bis-substituted o-carborane derivatives

Density functional theory(DFT) B3LYP at 6-31G* level was employed to optimize the structures of a series of 12-vertex bis-substituted o-carborane derivatives. On the basis of obtaining stable molecular configuration, combined with finite field(FF) method and time-dependent density-functional theory(TD-DFT), the second-order NLO property and molecular electric spectrum was calculated. The results indicate that 12-vertex bis-substituted o-carborane shows the ability to pull an electron. When 12-vertex bis-substituted o-carborane forms D-pi-A structure with organic group, it can be regard as a good acceptor. When donor or bridge has fine Conjugate property, 12-vertex bis-substituted o-carborane will show a stronger ability to pull an electron and the second-order NLO response of the molecules will increase.