ANISOTROPIC 2ND-ORDER NONLINEARITIES OF ORGANIC MONOLAYERS

Monolayers prepared from hemicyanine chromophores of high second-order nonlinearity (=1.3×10-26 esu at resonance) have been used to study anisotropies of the concomitant (2)-susceptibility tensor. All components of this third-rank tensor have been determined by Fourier analysis of the anisotropic coverage density Ns() with respect to the angle of rotation about surface normal. Depending on the preparation both Cs and C2v symmetry could be identified. © 1990 The American Physical Society.