RUI: Synthesis and Photophysical Studies of Transition Metal Alkynyl Complexes for Applications in Photochemical Molecular Devices

Furman University, Greenville SC

Investigators

Abstract

In this project funded by the Chemical Synthesis Program of the Chemistry Division, Professor Paul Wagenknecht of the Department of Chemistry at Furman University will develop new classes of transition metal alkynyl complexes with interesting optoelectronic properties. The goal of this research is to exploit the characteristics of these transition metal alkynyl complexes for the development of optoelectronic devices, namely near-infrared luminescent sensors, organic light emitting diodes, and systems for the conversion of solar energy into stored chemical energy or electricity (e.g. dye-sensitized solar cells). In addition, this project will provide excellent training of undergraduate, masters, and postdoctoral students in the area of device chemistry. Transition metal alkynyl complexes display a rich array of photophysical properties where substituted alkynyl ligands can be used both for the tuning of excited states and as conduits for electron- and energy-transfer. The proposed syntheses include modifications designed to probe the relationship between excited state photophysics and molecular architecture. In this project, three classes of new transition metal alkynyl complexes will be prepared to answer the following questions: 1) Can alkynyl-diimine ligands be used to facilitate Cr(III) sensitization of near-infrared lanthanide emission and how is the rate of the Cr to Ln energy transfer affected by the molecular architecture? 2) How does the inclusion of the high field strength trifluoropropynyl ligand impact the excited states of emissive complexes of interest for organic light emitting diodes? 3) Can the redox properties of the Fe(II) to Ti(IV) metal-to-metal charge-transfer excited state in alkynyl bridged Ti(IV)-Fe(II) assemblies be controlled and exploited for the conversion of solar energy into stored chemical energy?