Hyperpolarizability of an aromatic polyester

Abstract

The dependence of the degree of polymerization (n) for poly (p-hydroxybenzoic acid) on its dipóle moment (μ) and hyperpolanzabiUty (β) shows a high linearity for B3LYP and MP2 calculations. Both μ and β indicate that B3LYP/6-31G(d) gives higher values than those of MP2/6-31G (d). In addition, for all the basis sets considered here, μ and β show a high linearity with n. For both B3LYP and MP2, (i and ß calculated with 6-31G(d) and6-311G(d) give similar values, while those calculated with 6-31+ G(d) and6-311+G(d) give similar values, also. Furthermore, it was found that the addition of a diffuse function improves μ and β values. © 2010 The Society of Polymer Science.