Using 12CO and 13CO liganded protein and 406 nm laser excitation, multiple stretching (upsilon(Fe-CO), upsilon(C-O)) and bending (delta(Fe-C-O)) modes have been identified in the resonance Raman spectra of monomeric and polymeric Glycera hemoglobins. While the monomer fraction Glycera dibranchiata hemoglobin has upsilon(Fe-CO) = 496 cm-1, two distinct upsilon(Fe-CO) modes are found at 498 cm-1 ...

We report here a series of four- and five-coordinate Fe model complexes that feature an axial tri(silyl)methyl ligand positioned trans to a substrate-binding site. This arrangement is used to crudely model a single-belt Fe site of the FeMo-cofactor that might bind N2 at a position trans to the interstitial C atom. Reduction of a trigonal pyramidal Fe(I) complex leads to uptake of N2 and subsequ...

24 Geobacter species are important Fe(III) reducers in a diversity of soils and sediments. 25 Mechanisms for Fe(III) oxide reduction have been studied in detail in Geobacter sulfurreducens, 26 but a number of the most thoroughly studied outer surface components of G. sulfurreducens, 27 particularly c-type cytochromes, are not well conserved among Geobacter species. In order to 28 identify cellu...

Iron (Fe) is widely suspected as a key controlling factor of N2 fixation due to the high Fe content of nitrogenase and photosynthetic enzymes complex, and to its low concentrations in oceanic surface seawaters. The influence of Fe limitation on the recently discovered unicellular diazotrophic cyanobacteria (UCYN) is poorly understood despite their biogeochemical importance in the carbon and nit...

E SR has been used in the study of iron(I)-nitrosyl complexes w ith organic ligands in solution. Four types of complexes have been identified on basis of the ESR param eters, namely Fe (NO) L 5, Fe (NO) L 2, Fe (NO)2L 2, and Fe (NO)2L. In the iron-nitrosyl complexes with the organic ligands used, the groups more often involved in the coordination are: —C —N H 2; —C —N H ; — C = 0 ; and —C = S (...

Production of Fe-C alloy powders by mechanical alloying was studied. Fe and graphite elemental powder mixtures containing 0.8 and 1.5wt.% graphite were mechanically alloyed using a planetary ball mill. The structural changes of powder particles during mechanical alloying were studied by x-ray diffractometery, scanning electron microscopy and microhardness measurements. For both compositions, me...

In the title compound, [Fe(C11H20N2)2(CO)3], the Fe atom shows a distorted trigonal-bipyramidal geometry with three carbonyl and two carbene ligands. The latter have a cis arrangement, with a C-Fe-C angle of 90.60 (7)°. The Fe atom lies 0.007 (1) Å above the basal plane defined by two carbonyl and one carbene C atoms. The mol-ecular structure is closely related to that of the isomolecular but n...

In the title compound, (C(5)H(7)N(2))[Fe(C(7)H(3)NO(4))(2)] or [2-apyH][Fe(pydc)(2)], the asymmetric unit contains an [Fe(pydc)(2)](-) (pydc is pyridine-2,6-dicarboxyl-ate) anion and a protonated 2-amino-pyridine cation ([2-apyH](+)). The complex anion contains an Fe(III) atom within a distorted octahedral FeN(2)O(4) coordination geometry. N-H⋯O and C-H⋯O hydrogen bonding, offset π-π stacking [...

The trinuclear title compound, [Fe3(C3H6S2)2(CO)7], is a mixed-valent Fe(I)/Fe(II) complex and crystallizes with two mol-ecules of similar configuration in the asymmetric unit. The three Fe atoms in each mol-ecule display a bent arrangement [Fe-Fe-Fe = 156.22 (4) and 157.06 (3)°]. Both outer Fe(I) atoms are six-coordinated in a distorted ocahedral coordination geometry defined by the bridging F...