Group VIII transition metal complexes for nonlinear optical switching

Abstract

Metal alkynyl complexes have been shown to be potentially useful third-order nonlinear optical switches, with large two-photon absorption cross-sections and strong changes in photon absorption properties on oxidation. By forming multinuclear complexes, switches with more then two states can be made. Chapter 1 presents an introduction to nonlinear optics and reviews some inorganic materials which have had their nonlinear optical properties measured. Chapter 2 details new synthetic routes into binuclear complexes incorporating an osmtum chloro-alkynyl metal centre. Structural, electrochemical and spectroelectrochemical studies on selected examples have been carried out. Chapter 3 details new facile synthetic routes into osmtum ammine-alkynyl and osmium bis-alkyny1 complexes. Synthesis of osmium and ruthenium binuclear and trinuclear complexes with both diethyny1 and triethyny1 bridges between the metal atoms has been explored. Structural, electrochemical, spectroelectrochemical and theoretical studies have been carried out on selected complexes. Chapter 4 reports the synthesis of a number of branched multinuclear complexes incorporating both osmium and ruthenium metal atoms. Electrochemical and spectroelectrochemical studies have been carried out on selected examples. The Z-scan technique has been used to investigate the third-order nonlinear optical properties of a number of linear and branched bimetallic complexes, showing large effects but some photo-induced instability. Chapter 5 details the formation of a number of new mononuclear and unsymmetrical binuclear iron alkynyl complexes. The electrochemical and spectroelectrochemical behaviour of the complexes exhibiting a reversible redox process has been explored. - provided by Candidate. Show more