Recently, the complex cation [(cyclam-ac)Fe(III)(N3)](+) has been used in solid matrices under cryogenic conditions as a photochemical precursor for an octahedral iron nitride containing the metal at the remarkably high oxidation state +5. Here, we study the photochemical primary events of this complex cation in liquid solution at room temperature using femtosecond time-resolved mid-infrared (f...

Axial ligand substitution of a mononuclear nonheme oxoiron(IV) complex, [FeIV(O)(TMC)(NCCH3)]2+ (1) (TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane), leads to the formation of new FeIV=O species with relatively intense electronic absorption features in the near-UV region. The presence of these near-UV features allowed us to make the first observation of Fe=O vibrations of S = 1 mo...

Acyclic pyrazine-2-carboxamide and thioether containing hexadentate ligand 1,4-bis[o-(pyrazine-2-carboxamidophenyl)]-1,4-dithiobutane (H(2)bpzctb), in its deprotonated form, has afforded light brown [Ni(II)(bpzctb)](1)(S=1) and green [Cu(II)(bpzctb)](2)(S=1/2) complexes. The crystal structures of 1.CH(3)OH and 2.CH(2)Cl(2) revealed that in these complexes the ligand coordinates in a hexadentate...

Unimolecular gas-phase laser-photodissociation reaction mechanisms of open-shell lanthanide cyclopentadienyl complexes, Ln(Cp)3 and Ln(TMCp)3, are analyzed from experimental and computational perspectives. The most probable pathways for the photoreactions are inferred from photoionization time-of-flight mass spectrometry (PI-TOF-MS), which provides the sequence of reaction intermediates and the...

The transition metal complexes [Ru(dmb)3] and [Ru(dpb)3], where dmb is 4,4′-dimethyl-2,2′-bipyridine and dpb is 4,4′-diphenyl-2,2′-bipyridine, have been studied by femtosecond visible electronic absorption spectroscopy. Spectroelectrochemical measurements in conjunction with nanosecond time-resolved absorption spectroscopy allow for the assignment of various features in the excited-state differ...

The preparation of Os2(TiPB)4Cl2 (1; TiPB = 2,4,6-triisopropylbenzoate) and Os2(TiPB)2(OAc)2Cl2 (2) by carboxylate exchange reactions with Os2(OAc)4Cl2 is reported. The structure of 1 has been determined by single-crystal X-ray studies, and shows a paddlewheel arrangement of the ligands about the triply bonded diosmium core. Both compounds have magnetic moments at room temperature that are cons...

Iron species have essential influence on the environmental/geochemical behaviors of arsenic in water and soil. Colloidal ferric hydroxide (CFH) induces photooxidation arsenite (As(III)) to arsenate (As(V)) at neutral pH through surface complexation ligand-to-metal charge transfer (LMCT). However, effect co-existing natural organic matter (NOM) complexation-photolysis this process has remained u...

[Ru(terpy)(bpy)(L)]PF6 complexes, where terpy is 2,2΄:6′,2″– terpyridine, bpy is 2,2΄ - bipyridine and L is monoanions of  4 - bromophenylcyanamide (4 - Brpcyd), 4-methoxyphenylcyanamide (4 - MeOPcyd), 2, 4 - dibromophenylcyanamide (2,4 - Br2pcyd), 2,4-dimethylphenylcyanamide (2,4 - Me2pcyd), 2 - methylphenylcyanamide  (2 ...

Superoxide reductases (SORs) belong to a new class of metalloenzymes that degrade superoxide by reducing it to hydrogen peroxide. These enzymes contain a catalytic iron site that cycles between the Fe(II) and Fe(III) states during catalysis. A key step in the reduction of superoxide has been suggested to involve HO(2) binding to Fe(II), followed by innersphere electron transfer to afford an Fe(...

Three novel non-heme micro-oxo-bridged diiron(III) complexes [Fe2(micro-O)(L1)2] 2, where H2(L1) is N,N'-o-phenylenebis(salicylideneimine), [Fe2(micro-O)(L2)2].2H2O 4, where H2(L2) is N,N'-o-phenylenebis(3,5-di-tert-butylsalicylideneimine), and [Fe2(micro-O)(L3)2] 6, where H2(L3)=1,4-bis(2-hydroxybenzyl)-1,4-diazepane, have been isolated and studied as catalysts for the selective oxidative tran...