Ab initio prediction of extremely large first hyperpolarizability of polyphosphaacetylene and polyphosphasilyne

D.Y. Zhang , Claude Pouchan (1) , E.A. Perpète , D. Jacquemin

1 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

Calculations at MP2/6-31G(d) level predict a very large first hyperpolarizability (β) for two phosphorus-containing oligomers, namely, polyphosphaacetylene, -(PCH)n- and polyphosphasilyne, -(PSiH)n-, i.e., 212 777 and 90 811 a.u., respectively, at n = 16. These values are 5.3 and 2.3 times of that for the nitrogen analogue of polyphosphaacetylene, that is, polymethineimine. In striking contrast, polyborophosphene, -(PHBH)n-, is predicted to have extremely small β values, with a β/n value approaching zero at large n. The causes for the relative β values in these four series are discussed, in light of the bonding structure, the π bond strength, the size of the nuclei, and the degree of delocalization. © 2005 Elsevier B.V. All rights reserved.

Domaines: Chimie théorique et/ou physique

D.Y. Zhang, Claude Pouchan, E.A. Perpète, D. Jacquemin. Ab initio prediction of extremely large first hyperpolarizability of polyphosphaacetylene and polyphosphasilyne. Chemical Physics Letters, 2005, 416 (4-6), pp.277-281. ⟨10.1016/j.cplett.2005.09.095⟩. ⟨hal-01598743⟩