Spectroscopy K-edge X-ray absorption

Szilagyi, R. K., and Schwab, D. E. (2005). Sulfur K-edge X-ray absorption spectroscopy as an experimental probe for S-nitroso proteins. Biochem. Biophys. Res. Comm. 330, 60-63. [Pg.779]

Sulfur K-Edge X-ray Absorption Spectroscopy of Petroleum Asphaltenes and Model Compounds... [Pg.223]

The utility of sulfur K-edge X-ray absorption spectroscopy for the determination and quantification of sulfur forms in nonvolatile hydrocarbons has been investigated. X-ray Absorption Near Edge Structure (XANES) spectra were obtained for a selected group of model compounds, for several petroleum asphaltene samples and for Rasa coal. For the model compounds the sulfur XANES was found to vary widely from compound to compound, and to provide a fingerprint for the form of sulfur involved. The use of third derivatives of the spectra enabled discrimination of mixtures of sulfide and thiophenic model compounds, and allowed approximate quantification of the amount of each component in the mixtures, in the asphaltene samples and the coal. These results represent the first demonstration that nonvolatile sulfide and thiophenic sulfur forms can be distinguished and approximately quantified by direct measurement. [Pg.223]

Vanadium K-edge X-ray absorption spectroscopy has provided the most detailed information on the environment of V in the VFe proteins. Data for the VFe proteins of A. chroococcum and A. vinelandii are very similar (33, 34). The edge and near-edge structures of these spectra, which reflect coordination geometry and probable oxidation level of the absorbing atom, are both similar to the complex VFe3S4Cl3[HCON(CH3)2]3. The relatively low intensity of the pre-... [Pg.91]

Evans J, O Neill L, Kambhampati VL, Rayner G, Turin S, Genge A, Dent AJ, Neisius T (2002) Structural characterisation of solution species implicated in the palladium-catalysed Heck reaction by Pd K-edge X-ray absorption spectroscopy palladium acetate as a catalyst precursor. J Chem Soc, Dalton Trans 10 2207... [Pg.414]

Structure information on the FeVco of vanadium nitrogenases has been obtained from iron and vanadium K-edge X-ray absorption spectroscopy (XAS) (for background information, see Section 3.6.), in particular so from the extended (EXAFS) region. [Pg.133]

Rose K, Shadle SE, Eidsness MK, Kurtz DM, Scott RA, Hedman B, Hodgson KO, Solomon El (1998) Investigation of iron-sulfur covalency in rubredoxins and a model system using sulfur K-edge X-ray absorption spectroscopy. J Am Chem Soc 120 10743-10747... [Pg.150]

The copper(III) oxidation state of the bis(/i-oxo) core has been confirmed directly by a Cu K-edge X-ray absorption spectroscopy (XAS) study on compound (7). " All complexes exhibit two intense... [Pg.381]

Dey A, Jetmey FE, Adams MK et al (2007) Sulfur K-edge X-ray absorption spectroscopy and density functional theory calculations on superoxide reductase role of the axial thiolate in reactivity. J Am Chem Soc 129 12418-12431... [Pg.33]

Characterization data (IR, molecular mass and S and Mo K-edge X-ray absorption spectroscopy) indicated that the Tp MoOS(OAr) compounds participate in a monomer(26)-dimer(29) equilibrium, favouring an oxosul-fido-Mo(vi) monomer in solution. " The compounds isolated depend on the steric bulk of the phenolate co-ligand. For example, the phenolate derivative crystallizes as dimeric [Tp MoOS(OPh)]2, which features Mo(v) centres linked by a bent p-disulfido bridge with Mo-S and S-S distances of 2.324(1) and 2.095(2) A, respectively. Figure 7.6(a) shows the closely related structure of [Tp "MoOS(OC6H3BuV3,5)]2 and the nature of the redox rearrangements involved in the monomer-dimer equilibrium. [Pg.227]

Elizabe. L. Yeo. L. Harris. K.D.M. Sankar. G. Thomas. J.M. Conformational properties of guest molecules in constrained solid-state environments Bromine K-edge x-ray absorption spectroscopy of 2-bromoalkane/urea inclusion compounds. Chem. Mater. 1998, 10. 1220. Shang, Q. Y., Dou, X. Hudson, B.S. Off-axis orientation of the electronic transition moment for a linear conjugated polyene. Nature 1991, 352. 703. [Pg.1549]

Lu TT, Lai SH et al (2011) Discrimination of mononuclear and dinuclear dinitrosyl iron complexes (DNICs) by S K-edge X-ray absorption spectroscopy insight into the electronic structure and reactivity of DNICs. Inorg Chem 50 5396-5406... [Pg.101]

Sulfur-K-edge X-ray absorption spectroscopy (XAS) was demonstrated to provide a superior level of insight on elucidating the electronic stmcture of the Fe(NO)2 core of DNlCs. XAS allows a direct probing of the chemical forms of sulfur, bonding mode, and covalency of the metal-sulfur bond which... [Pg.151]

Glaser T, Hedman B et al (2000) Ligand K-edge X-ray absorption spectroscopy a direct probe of ligand-metal covaltatcy. Acc Chem Res 33 859-868... [Pg.162]

Rompel A, Cinco RM et al (1998) SuUur K-edge X-ray absorption spectroscopy a spectroscopic tool to examine the redox state of S-contairring metabolites in vivo. Proc Natl Acad Sci 95 6122-6127... [Pg.162]

TardCTholt AL, Wang JJ et al (2010) SuUur K-edge X-ray absorption spectroscopy and density functional calculations on Mo (TV) and Mo (VI)-O bis-dithiolenes insights into the mechanism of Oxo transfer in DMSO rednedase and related fimctional analogues. J Am Chem Soc 132 8359-8371... [Pg.162]

Sun N, Liu LV et al (2010) S K-edge X-ray absorption spectroscopy and density functional theory studies of high and low spin FeNO thiolate complexes exchange stabilization of electron delocalization in FeNO and Fe02 - Inorg Chem 50 427-436... [Pg.163]

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