Molecular and Electronic Structure of [MnVN(cyclam−acetato)]PF6. A Combined Experimental and DFT Study
journal contributionposted on 07.07.2001, 00:00 by Craig A. Grapperhaus, Eckhard Bill, Thomas Weyhermüller, Frank Neese, Karl Wieghardt
From the reaction of Li(cyclam−acetate), MnCl2·4H2O, and KPF6 in methanol brown microcrystals of [MnIIICl(cyclam−acetato)]PF6 (1) were obtained in the presence of air (cyclam−acetic acid = 1,4,8,11-tetraazacyclotetradecane-1-acetic acid). The reaction of 1 in aqueous NH3 solution with NaOCl produced blue crystals of [MnVN(cyclam−acetato)]PF6 (2). Complexes 1 and 2 were characterized by single-crystal X-ray crystallography, IR and Raman, electronic absorption, and 1H, 13C, and 15N NMR spectroscopies. Their magnetochemistry as well as their electrochemistry have been investigated. The complexes [MnN(cyclam−acetato)]+/2+ were studied by theoretical calculations at the DFT and semiempirical levels in order to obtain more insight into the ground and excited states of the MnV⋮N unit. Structural and spectroscopic parameters were successfully calculated and compared to experiment. A pictorial description of the bonding has been developed.