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Title: Highly Oxidizing Excited States of Re and Tc Complexes

Abstract

Like the Re analog, the ligand-to-metal charge transfer (LMCT) excited state of [Tc(dmpe)3]2+* (dmpe is bis-1,2-(dimethylphosphino)ethane) is luminescent in solution at room temperature. Surprisingly, both [M(dmpe)3]2+* species have extremely oxidizing excited state potentials (ESPs)-the highest for any simple coordination complex of a transition metal. Furthermore, this potential is available using a photon of visible light (calculated for M=Re(Tc); E1/2*=+2.61(2.52)V vs. SCE; λmax =526(585) nm). Using a Rehm-Weller analysis with a series of aromatic hydrocarbons as electron transfer quenchers, E1/2(Re2+*/Re+) has been determined to be 2.58 V, in good agreement with the calculated value. Both [M(dmpe)3]2+* species are quenched by chloride ion and both can function as excited state oxidants in water solution.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
899149
Report Number(s):
PNNL-SA-51880
12298; KP1302000; TRN: US0701742
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society, 128(51):16494-16495
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AQUEOUS SOLUTIONS; AROMATICS; CHLORIDES; ELECTRON TRANSFER; EXCITED STATES; OXIDIZERS; PHOTONS; TRANSITION ELEMENTS; luminescent, highly oxidizing excited state, photo oxidation, technetium, rhenium; Environmental Molecular Sciences Laboratory

Citation Formats

Del Negro, Andy S., Seliskar, Carl J., Heineman, William R., Hightower, Sean E., Bryan, Samuel A., and Sullivan, Brian P.. Highly Oxidizing Excited States of Re and Tc Complexes. United States: N. p., 2006. Web. doi:10.1021/ja067114g.
Del Negro, Andy S., Seliskar, Carl J., Heineman, William R., Hightower, Sean E., Bryan, Samuel A., & Sullivan, Brian P.. Highly Oxidizing Excited States of Re and Tc Complexes. United States. doi:10.1021/ja067114g.
Del Negro, Andy S., Seliskar, Carl J., Heineman, William R., Hightower, Sean E., Bryan, Samuel A., and Sullivan, Brian P.. Wed . "Highly Oxidizing Excited States of Re and Tc Complexes". United States. doi:10.1021/ja067114g.
@article{osti_899149,
title = {Highly Oxidizing Excited States of Re and Tc Complexes},
author = {Del Negro, Andy S. and Seliskar, Carl J. and Heineman, William R. and Hightower, Sean E. and Bryan, Samuel A. and Sullivan, Brian P.},
abstractNote = {Like the Re analog, the ligand-to-metal charge transfer (LMCT) excited state of [Tc(dmpe)3]2+* (dmpe is bis-1,2-(dimethylphosphino)ethane) is luminescent in solution at room temperature. Surprisingly, both [M(dmpe)3]2+* species have extremely oxidizing excited state potentials (ESPs)-the highest for any simple coordination complex of a transition metal. Furthermore, this potential is available using a photon of visible light (calculated for M=Re(Tc); E1/2*=+2.61(2.52)V vs. SCE; λmax =526(585) nm). Using a Rehm-Weller analysis with a series of aromatic hydrocarbons as electron transfer quenchers, E1/2(Re2+*/Re+) has been determined to be 2.58 V, in good agreement with the calculated value. Both [M(dmpe)3]2+* species are quenched by chloride ion and both can function as excited state oxidants in water solution.},
doi = {10.1021/ja067114g},
journal = {Journal of the American Chemical Society, 128(51):16494-16495},
number = ,
volume = ,
place = {United States},
year = {Wed Dec 27 00:00:00 EST 2006},
month = {Wed Dec 27 00:00:00 EST 2006}
}
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