First Principles Treatment of Configuration Optimizations, Excited-State Properties, and Dynamic Third-Order Polarizabilities of Chloro-Metal Phthalocyanines MPcCl (M ) Al, Ga, In)

We report optimized geometrical structures at the RHF/6-31G* and 3-21G levels, the properties of excited states using time-dependent density functional theory based on the B3LYP/3-21G* level, and the frequency dependence of third-order nonlinear optical polarizabilities γ in different optical processes of THG, EFISHG, and DFWM by using B3LYP coupled with the sum over states methods (SOS//TDDFT-B3LYP/3-21G*) for the MPcCl (M = Al, Ga, In) molecules. The calculated results show that both the distance of the central atom from the Pc plane and the γ value increase in the order of AlPcCl < GaPcCl < InPcCl. The dispersion behaviors of the three different optical processes are discussed, and the calculated susceptibilities of χ(3)(−ω; ω, ω, −ω) match the measured values and correspond to the varied trends in the measurements of AlPcCl < GaPcCl < InPcCl films. It is found that a large ionic radius of M makes a large distortion away from C4v symmetry and that a larger d-electron transfer results in a red shift in ...