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Updated: Jul 12, 2026
A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks
Published on: April 28, 2023
Nonlinear optical and two-photon absorption properties of octupolar tris(bipyridyl)metal complexes
Christophe Feuvrie1, Olivier Maury, Hubert Le Bozec
1UMR 6226 CNRS-Université de Rennes1, Campus de Beaulieu, 35042 Rennes Cedex, France.
Abstract:
The linear (absorption and emission) and nonlinear optical (NLO) properties of a series of D(3) [(Fe(II), Ru(II), Ni(II), Cu(II), Zn(II)] octupolar metal complexes featuring the 4,4'-bis[(dibutylamino)styryl]-2,2'-bipyridine ligand are reported. Zinc(II), nickel(II), and copper(II) complexes exhibit similar absorption spectra in the visible region (lambda(ILCT) = 474-476 nm) which are assigned to intraligand charge-transfer (ILCT) bands. The quadratic and cubic NLO properties are strongly influenced by the nature of the metallic center. Harmonic light scattering studies at lambda = 1.91 microm reveal that these chromophores display large first hyperpolarizabilities beta(1.91) in the range of (211-340) x 10(-30) esu; replacing the Zn(II) metal ion by Ni(II) or Cu(II) results in a decrease of the static beta(0) coefficient by a factor of 1.5-1.6. Z-scan measurements at 765 and 965 nm reveal relatively large two-photon absorption cross-sections [650 < sigma(2) < 2200 GM], showing that both beta and sigma(2) values can be tuned by simple modification of the metal ion.
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