Photothermal studies of the photodegradation of (μ-peroxo)(μ-hydroxo) bis[bis(bipyridyl)Co(III)] and (μ-peroxo)(μ-hydroxo) bis[bis(phenanthroline)Co(III)] complexes in water Article

Mikšovská, J, Larsen, RW. (2003). Photothermal studies of the photodegradation of (μ-peroxo)(μ-hydroxo) bis[bis(bipyridyl)Co(III)] and (μ-peroxo)(μ-hydroxo) bis[bis(phenanthroline)Co(III)] complexes in water . INORGANICA CHIMICA ACTA, 355 116-120. 10.1016/S0020-1693(03)00272-X

cited authors

  • Mikšovská, J; Larsen, RW

abstract

  • We report here thermodynamic parameters associated with the photodegradation of water soluble (μ-peroxo)(μ-hydroxo)bis[bis(bipyridyl) Co(III)] and (μ-peroxo)(μ-hydroxo)bis[bis(phenanthroline)Co(III)] complexes. Photolysis of these complexes results in the release of dioxygen and the formation of the (H2O)4·(L)2Co(II) complex where L=bipyridyl or phenanthroline. Photoacoustic calorimetry data reveals an enthalpy for photolysis of 71 kcal mol-1 with a corresponding molar volume change of +39 ml mol-1 for the bipyridine complex. For the corresponding phenanthroline complex an enthalpy change of 68 kcal mol-1 and molar volume change of +19 ml mol-1 are observed. These values are considered as a sum of the intrinsic volume changes due to the bond cleavage and bond formation and the volume change due to electrostriction. The larger volume change for the (μ-peroxo)(μ-hydroxo) bis[bis(bipyridyl)Co(III)] complex is attributed to a spin-state change of the Co ion upon photolysis which is not present in the (μ-peroxo)(μ-hydroxo) bis[bis(phenanthroline)Co(III)] photoproduct. © 2003 Elsevier B.V. All rights reserved.

publication date

  • November 20, 2003

published in

Digital Object Identifier (DOI)

start page

  • 116

end page

  • 120

volume

  • 355