title: Syntheses and spectroscopic and quadratic nonlinear optical properties of extended dipolar complexes with ruthenium(II) ammine electron donor and N-methylpyridinium acceptor groups.
abstract: In this paper, we describe the extremely unusual optical properties of Ru(II)-based electron donor-acceptor (D-A) polyene and some closely related chromophores. For three different polyene series, the intense, visible d-->pi* metal-to-ligand charge-transfer bands unexpectedly blue-shift as the number of E-ethylene units (n) increases from 1 to 3, and the static first hyperpolarizabilities beta(0) determined via hyper-Rayleigh scattering and Stark spectroscopy maximize at n = 2, in marked contrast to other known D-A polyenes in which beta(0) increases steadily with n. Time-dependent density-functional theory and finite field calculations verify these empirical trends, which arise from the orbital structures of the complexes. This study illustrates that transition metal-based nonlinear optical chromophores can show very different behavior when compared with their more thoroughly studied purely organic counterparts.
authors.affiliation: Department of Chemistry, University of Manchester, Oxford Road, Manchester, United Kingdom M13 9PL. b.coe@man.ac.uk
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Coe
authors.forename: Lathe A
authors.initials: LA
authors.lastname: Jones
authors.forename: James A
authors.initials: JA
authors.lastname: Harris
authors.forename: Bruce S
authors.initials: BS
authors.lastname: Brunschwig
authors.forename: Inge
authors.initials: I
authors.lastname: Asselberghs
authors.forename: Koen
authors.initials: K
authors.lastname: Clays
authors.forename: André
authors.initials: A
authors.lastname: Persoons
authors.forename: Javier
authors.initials: J
authors.lastname: Garín
authors.forename: Jesús
authors.initials: J
authors.lastname: Orduna