Molecular first hyperpolarizability of push-pull polyenes: Relationship between electronic and vibrational contribution by a two-state model - Reply

In this paper we justify the approximations we have used in the treatment of Raman intensities in the paper being commented on [C. Castiglioni, M. Del Zoppo, and G. Zerbi, Phys. Rev. B 53, 13 319 (1996)]. This discussion gives further support to the applicability of the expressions presented by Castiglioni, Del Zoppo, and Zerbi [Phys. Rev. B 53, 13 319 (1996)], which relate electronic and vibrational first hyperpolarizability of push-pull polyenes.