Experimental determination of the first hyperpolarizability of new chiral and achiral octupolar tertiary amines by hyper-Rayleigh scattering

Tertiary amines with a fully sp(2)-hybridized nitrogen as central atom and acceptor-substituted phenyl or diazabiphenyl units as peripheral groups (hereafter shortly referred to as ''sidewing-octupoles'') exhibit relatively high beta values at short absorption wavelengths. Donor substitution of those sidewings results in a drop in the first hyperpolarizability beta at comparable absorption wavelengths. One of the octupoles investigated has three chiral carbon atoms so that it should crystallize in a noncentrosymmetric structure. This is interesting since there is no other way to obtain macroscopic chi((2)) structures from octupolar molecules due to the lack of a permanent dipole moment. The first hyperpolarizability beta of these octupolar molecules has been measured via the recently developed hyper-Rayleigh-scattering technique (HRS) at 1064 nm.