Excited state properties of Quinoxaline-substituted Platinum 1,2-Enedithiolates

Show full item record

Title: Excited state properties of Quinoxaline-substituted Platinum 1,2-Enedithiolates
Author: Kaiwar, Sharada; Vodacek, Anthony; Blough, Neil; Pilato, Robert
Abstract: The complexes (dppe)M{S2C2(2-quinoxaline)(R)}, where dppe = (diphenylphosphinoethane, M = Ni, Pd, and Pt, and R = H and Me, have as their lowest-energy band an intraligand charge transfer transition (ILCT). Excitation of deaerated solutions of (dppe)Pt{S2C2(2-quinoxaline)(R)} lead to emissions from an 1ILCT* and an 3ILCT*. The lifetimes of these excited states (ô) and the quantum yields for the emissions ( ) for (dppe)Pt{S2C2(2- quinoxaline)(H)} in CH3CN are 1ô = 0.16 ns,1 () = 0.005 and 3ô = 3.3, 3 () = 0.01, respectively. The 3ILCT* of these quinoxaline-substituted complexes can undergo a diverse suite of excited state reactions, including electron, proton, and hydrogen atom transfers. The second order rate constants (kq) for the quenching of the 3ILCT* emission by acids increases with the thermodynamic driving force for the excited state proton transfer, an observation consistent with excited state electron and hydrogen atom transfers. Dihydroquinone and p-methoxyphenol are substantially better quenching agents than excited state proton transfer would predict and thermodynamic calculations suggest that they quench the 3ILCT* by hydrogen atom transfer (Refer to PDF file for exact formulas).
Description: RIT community members may access full-text via RIT Libraries licensed databases: http://library.rit.edu/databases/
Record URI: http://hdl.handle.net/1850/4362
Publishers URL: http://dx.doi.org/10.1021/ja9626998
Date: 1997-04-09

Files in this item

Files Size Format View

An open access version of this file is not available. Check "Publisher URL" field for access

This item appears in the following Collection(s)

Show full item record

Search RIT DML

Advanced Search