Three-dimensional nonlinear optical chromophores based on metal-to-ligand charge-transfer from ruthenium(II) or iron(II) centers.
In this article, we describe a series of new complex salts in which electron-rich transition-metal centers are coordinated to three electron-accepting N-methyl/aryl-2,2':4,4' ':4',4' ''-quaterpyridinium ligands. These complexes contain either Ru(II) or Fe(II) ions and have been characterized by using various techniques, including electronic absorption spectroscopy and cyclic voltammetry. Molecular quadratic nonlinear optical (NLO) responses beta have been determined by using hyper-Rayleigh scattering at 800 nm and also via Stark (electroabsorption) spectroscopic studies on the intense, visible d --> pi* metal-to-ligand charge-transfer bands. The latter experiments reveal that these putatively octupolar D(3) chromophores exhibit two substantial components of the beta tensor which are associated with transitions to dipolar excited states. Computations involving time-dependent density-functional theory and the finite field method serve to further illuminate the electronic structures and associated linear and NLO properties of the new chromophoric salts.
Coe
Benjamin J
BJ
School of Chemistry, University of Manchester, Manchester, UK. b.coe@man.ac.uk
Harris
James A
JA
Brunschwig
Bruce S
BS
Asselberghs
Inge
I
Clays
Koen
K
Garín
Javier
J
Orduna
Jesús
J
D007501:Iron / Q000737:chemistry*; D008024:Ligands; D008956:Models, Chemical; D015394:Molecular Structure; D009905:Optical Rotatory Dispersion; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*; D013237:Stereoisomerism
D008024:Ligands; D009942:Organometallic Compounds; D012428:Ruthenium; D007501:Iron