Nonlinear optical susceptibilities of triphenylbenzene, resorcinol, and metanitroaniline

The nonlinear optical susceptibilities of three π-bonded, molecular systems, (symmetrical triphenylbenzene, resorcinol, and metanitroaniline) possessing large variations in dipole moments (δμ≳50:1) are reported. The results show that the proportionality constant (k) which relates the vector portion of the nonlinear susceptibility (v) to the crystalline spontaneous polarization (Ps), viz., (v=kPs) is ∼30 times larger for these π-bonded systems than for σ-bonded systems and that the spontaneous polarization of triphenylbenzene is ∼0.1 μC/cm2.