Pressure effects on bimolecular reductive quenching of the platinum(II) dimer Pt sub 2 (. mu. -. eta. sup 2 -H sub 2 P sub 2 O sub 5 ) sub 4 sup 4 minus by organic substrates
- Univ. of California, Santa Barbara (USA)
Pressure effects are reported for the quenching dynamics of the lowest energy excited state of the d{sup 8}-d{sup 8} dimer Pt{sub 2}({mu}-{eta}{sup 2}-H{sub 2}P{sub 2}O{sub 5}){sub 4}{sup 4{minus}} ({sup 3}Pt{sub 2}*). Volumes of activation ({Delta}V{double dagger}) are reported for the H atom abstraction by {sup 3}Pt{sub 2}* from various organic substrates and for O{sub 2} quenching of {sup 3}Pt{sub 2}* in methanol solution. The H atom donors studied include a series of benzyl alcohols, allyl alcohol, tributyltin hydride, and benzyl methyl ether. Volumes of activation of {minus}5.4 {plus minus} 0.6 cm{sup 3} mol{sup {minus}1} and {minus}4.1 {plus minus} 0.7 cm{sup 3} mol{sup {minus}1} have been measured for quenching by benzyl alcohol and benzyl methyl ether, respectively. These negative {Delta}V{double dagger} values suggest as associative interaction between the excited state dimer and the H atom donor. The mechanistic implications of the pressure effects on the rates for other quenchers are discussed.
- OSTI ID:
- 5466832
- Journal Information:
- Journal of the American Chemical Society; (United States), Vol. 112:19; ISSN 0002-7863
- Country of Publication:
- United States
- Language:
- English
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