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[super 57]Fe Nuclear resonance vibrational spectroscopy (NRVS) is applied for identifying protein-bound dinitrosyl iron complexes. NRVS spectra for four iron dinitrosyl model compounds are used as benchmarks for identifying species formed in the reaction of Pyrrococcus furiosus ferredoxin D14C with nitric oxide.

The structures of zeolite-anchored organorhodium complexes undergoing conversions with gas-phase reactants are characterized by infrared spectra supported by calculations with density functional theory and analysis of the gas-phase products. The results have shown the presence of a new rhodium monohydride species by incorporating a [C.sub.2][H.sub.4] ligand.

The single-turnover-like reaction conditions at ?78 degree [Celsius] are used to obtain a new dark-brown species with ([[lambda].sub.max] = 396, 732, 843 nm) from dark-green ([[lambda].max] = 440, 611, 747 nm) complex of iron(III) meso-N-substituted corrole ([TBP.sub.8]Cz)[Fe.sup.III] ([TBP.sub.8]Cz = octakis(4-tert-butylphenyl)corrolazinato). Rapid-mixing stopped-flow UV-vis studies showed that the low-temperature dark-brown complex is generated as a short-lived intermediate at room temperature and EPR spectroscopic characterization established the complex as an antiferromagnetically coupled iron(IV)-oxo [pi]-cation-radical complex.

The reaction of the dichloride rac-(ebthi)Hf[Cl.sub.2] [ebthi = 1,2-ethylene,1,1E-bis([[eta].sup.5]-tetrahydroindenyl) with lithium in the presence of bis(trimethylsilyl)acetylene has produced the hafnacyclopropene rac-(ebthi)Hf([[eta].sup.2]-[Me.sub.3]Si[C.sub.2]Si[Me.sub.3]) (1-Hf). The reaction behavior of the alkyne complexes 1-M is examined by using the NMR experiments and comparing the results with ultraviolet/visible spectroscopy, indicating the existence of a bis-[pi]-complex prior to the formation of the hafnacyclopentene 2-Hf.

Static solid-state [super 35]Cl NMR spectra of the organometallic compounds are acquired with the quandrupolar Carr-Purcell Meiboom-Gill (QCPMG) sequence in a piecewise manner. Solid-state [super 35]Cl NMR spectroscopy is used for the structural characterization of chlorine-containing transition-metal and main-group systems.

The lowest bandgap, soluble, spray-processable polymer is produced by combining a strong donor, tris(dodecyloxy)phenyl)-dithieno[3,2-b:2',3'-d-pyrrole, with a strong acceptor, 4,8-dithien-2-yl-2[[lambda].sup.4][[delta].sup.2]-benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole. Transmission/absorption spectroscopy on single-walled carbon nanotubes (SWCNTs) and reflectance spectroscopy on gold are used for estimating the optical bandgap.

Helical lanthanide(III) complexes based on the chiral nonaazamacrocyclic amine (L) are isolated in enantiopure form and are characterized by spectroscopic methods. Circularly polarized luminescence on the MeOH solutions of Eu(III) and Tb(III) complexes have confirmed the presence of stable chiral emitting species and the observation of almost perfect mirror-image CPL spectra for these compounds with both enantiomeric forms of L.

An example of the mass spectrometric characterization of the benzylidene gold carbene is described. The chemical nature of the carbene is shown by its characteristic reactivity with olefins, which has included cross-metathesis and cyclopropanation.

The matrix isolation technique is combined with infrared spectroscopy and theoretical calculations are used to explore the reaction of [C[H.sub.3].sub.2]Zn with [O.sub.3] over a range of time scales. A new variable length concentric deposition technique is developed to study the time scale between twin and merged reaction times.

The diastereoisomeric complexes [[[(acac).sub.2]Ru([mu-QL)Ru[(acac).sub.2]].sup.n] (Q[L.sup.2-] = 1,4-dioxido-9,10-anthraquinone, n = +2, +1, 0, -1, -2) are obtained in neutral form as rac and meso isomers. The metal-ligand valence-state distribution in these complexes is assessed by using ultraviolet-visible-nearinfrared spectroelectrochemistry and EPR methods.

Well-resolved polarized absorption and luminescence spectra of a tetragonal chromium(II) complex are described. The analysis has shown that the [super 4][E.sub.g] excited-state Jahn-Teller distortion in the tetragonal title complex is similar to those described for high-symmetry, homoleptic complexes.

Kinetic studies are performed for the substitution of the first silyl ligand in [([Me.sub.3]N).sub.3]Ta[[Si[(Si[Me.sub.3]).sub.3]].sub.2] by Li[(THF).sub.3]SiBu[super i][Ph.sub.2] (THF = tetrahydrofuran). The results have shown that the reaction might follow a dissociative pathway in the presence of excess Li[(THF).sub.3]SiBu[super i][Ph.sub.2] and the polar solvent THF has promoted the substitution.

The formation of ordered three-dimensional structures in solutions of organometallic complexes in a thin film of supported ionic liquid is described. The ordering effects have led to a drastically reduced mobility of ionic liquid and complex molecules and it could be used to induce unusual properties in the supported complexes.

The design and covalent attachment of ferrocene (bis(eta(super 5)-cyclopentadienyl) iron(II), Fe) to the active site of azurin (Az) free copper and control of its redox properties by pH and residues around the secondary coordination sphere, are reported. Increasing water solubility of Fe, stabilizes ferrocenium species (Fe(super +)) and use of such redox active protein in oxidizing cytochrome c is also established.

Large parity violation energy differences of about 1 Hz for vibrational transitions in organometallic compounds are predicted. Organometallic compounds could also be useful for parity nonconservation (PNC) studies in high-resolution NMR or Mossbauer spectroscopy, where the natural line-width is sufficiently small is mentioned.

The synthesis and characterization of a simple organometallic compound containing CF, which is the simplest possible fluorocarbon, as a terminal ligand is reported. A combination of spectroscopic, crystallographic, and computational methodology defines a new compound, which is considered as a member of he family of metal-alkylidyne complexes and the first terminal compound of fluoromethylidyne.