Isoindole and isomeric heterocyclic donating substituents in ruthenium(II)nitrosyl complexes with large first hyperpolarizabilities and potential two-photon absorption capabilities: a computational approach

Abstract

A set of 22 ruthenium nitrosyl complexes of general formula [RuII(L)Cl2(NO)]+ is investigated computationally by the density functional theory. L is a terpyridine ligand substituted by different R isomers of formula C12H8N, either indole, isoindole, or carbazole, proposed as alternative donors to the electron-rich fluorene substituent. The computed resulting nonlinear optical (NLO) properties are found to strongly depend on the isomer. While the ruthenium complexes exhibit modest efficiencies at the second-order (two-photon absorption) level, some of the R isomers lead to complexes of enhanced capabilities in first order (b) nonlinear optics. The synthetic feasibility of these ligands is discussed.