Abstract: The nonlinear optical properties were calculated for the furan homologues including furan(C₄H₄O), thiophene(C₄H₄S), selenophene(C₄H₄Se) and tellurophene(C₄H₄Te), by time-dependent density functional theory(TDDFT) combined with sum-over-states(SOS) method. The calculated results show that the substitution of the heteroatom with heavy atoms systematically increases the polarizability α and second hyperpolarizability γ. The values of α and γ calculated by B3LYP, BLYP, SVWN and X_α functionals are similar. The calculated results indicate that the C₄H₄X exhibits a small dispersion in a width frequent zone. It is more available to be used for NLO materials.

Key words: Furan homologue, NLO property, TD-DFT, SOS method