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Luminescence of the nonclassical homoleptic metal carbonyl complex [Rh(CO4]+
Theodore W Bitner1, Jeffrey I Zink, Matthew D Havighurst
1Department of Chemistry and Biochemistry, University of California, Los Angeles 90095, USA.
Abstract:
The nonclassical [Rh(CO)(4)](+) cation is luminescent at low temperature with a peak maximum at 19640 cm(-1) and a full-width at half-maximum of 2900 cm(-1). Both the solution absorption and low-temperature solid-state luminescence spectra of the [Rh(CO)(4)](1-Et-CB(11)F(11)) salt are reported. The cesium salt of the [1-Et-CB(11)F(11)](-) counterion is also luminescent (with a peak maximum at 22650 cm(-1)), but the emission maximum of [Rh(CO)(4)](+) is lower in energy. The Rh-C bond length changes of approximately 0.07 A in the excited state are calculated. The calculated bond length changes in the nonclassical [Rh(CO)(4)](+) ion are not very different from those in classical complexes.
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