Structure and Electronic Properties of Extended Chromophores for Applications in Second-Order Nonlinear Optics

A structural and theoretical analysis of new 2-[(4-phenylazo)phenyl] benzoxazole chromophores of potential interest in the field of second-order nonlinear optics is presented. Computations predict comparatively high hyperpolarizabilities for most of the compounds in their equilibrium nuclear configuration, with a significant dependence upon some conformational degrees of freedom and independence upon some others. This behavior is rationalized in the frame of the two-level model and sheds light on the conjugation pattern of these new chromophores.