title: Applications of high-field (W-band) EPR to M-M bonded units (M = Cr, Mo): the first confirmed oxidation of a Cr2 4+ paddlewheel complex to a stable isostructural Cr2 5+ product.
abstract: The EPR spectra of [Cr(2)[(PhN)(2)CN(CH(2))(4)](4)]PF(6) and [Mo(2)(TiPB)(4)]PF(6) (TiPB = anion of 2,4,6-triisopropylbenzoic acid) at W-band are shown to have g values significantly lower than 2.00 and exhibit parallel and perpendicular components (not resolved at X-band). Therefore the unpaired electrons of the M(2)(5+) units must reside on metal-based (not ligand-based) orbitals. Thus, the chromium compound must be considered as the first confirmed oxidation product of a Cr(2)(4+) paddlewheel complex comparable to the Mo(2)(5+) compounds.
authors.affiliation: Department of Chemistry and Laboratory for Molecular Structure and Bonding, PO Box 30012, Texas A&M University, College Station 77842-3012, USA. cotton@tamu.edu
authors.forename: F Albert
authors.initials: FA
authors.lastname: Cotton
authors.forename: Naresh S
authors.initials: NS
authors.lastname: Dalal
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Hillard
authors.forename: Penglin
authors.initials: P
authors.lastname: Huang
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Murillo
authors.forename: Chris M
authors.initials: CM
authors.lastname: Ramsey