title: Isovalent and mixed-valent diruthenium complexes [(acac)2RuII (-bpytz)RuII(acac)2] and [(acac)2RuII(-bpytz)RuIII(acac)2](ClO4) (acac = acetylacetonate and bpytz = 3,6-bis(3,5-dimethylpyrazolyl)-1,2,4,5-tetrazine): synthesis, spectroelectrochemical, and epr investigation .
abstract: The title compounds involving the structurally characterized bridging ligand bpytz were characterized, showing very strong electrochemical stabilization of the mixed-valent RuIIRuIII state (Kc = 10(13.9)) but no detectable (epsilon < 20 M(-1) cm(-1)) intervalence charge-transfer band in the infrared region. In situ reduction of the neutral precursor produces a diruthenium(II) complex of the bpytz radical anion according to EPR spectroscopy, whereas oxidation of the mixed-valent form leads to a diruthenium(III) species.
authors.affiliation: Department of Chemistry, Indian Institute of Technology-Bombay, Powai, Mumbai-400076, India.
authors.forename: Srikanta
authors.initials: S
authors.lastname: Patra
authors.forename: Biprajit
authors.initials: B
authors.lastname: Sarkar
authors.forename: Sandeep
authors.initials: S
authors.lastname: Ghumaan
authors.forename: Jan
authors.initials: J
authors.lastname: Fiedler
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kaim
authors.forename: Goutam Kumar
authors.initials: GK
authors.lastname: Lahiri