In this study, we perform steady-state and time-resolved X-ray absorption spectroscopy (XAS) on the iron K-edge of [Fe(tren(py)3)](PF6)2 dissolved in acetonitrile solution. Static XAS measurements on the low-spin parent compound and its high-spin analogue, [Fe(tren(6-Me-py)3)](PF6)2, reveal distinct spectroscopic signatures for the two spin states in the X-ray absorption near-edge structure (XA...

We have carried out a series of density functional theory (DFT) calculations to predict the 57Fe Mössbauer quadrupole splittings (DeltaEQ) and isomer shifts (deltaFe) for the nitrosyl complex of isopenicillin N synthase with the substrate delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine (IPNS.ACV.NO) and an {FeNO}7 (S = 3/2) model system, FeL(NO)(N3)2 (L = N,N',N' '-trimethyl-1,4,7-triazacyclo...

We present two novel coordination polymers based on octacyanidorhenate(V) metalloligands and Fe(II) complexes with different positional isomers of a benzylpyridine ligand, namely 3-benzylpyridine (3-benzpy) that leads to two-dimensional {[FeII(3-benzpy)4]3[ReV(CN)8]2}·2H2O (1) network 4-benzylpyridine (4-benzpy) giving three-dimensional {[FeII(4-benzpy)4]5[ReV(CN)8]3}(ClO4)·2(4-benzpy)·6H2O·MeO...

The formation and disappearance of a photosensitive species during the reaction of reduced cytochrome c oxidase (putatively a3II.O2), EC 1.9.3.1, has been followed by (a) mixing a3II.CO with O2 in a stopped flow apparatus; (b) initiating the oxygen-oxidase reaction by removing CO with a laser flash; (c) probing the reaction mixture for photosensitivity with a second laser flash. Photosensitivit...

The title compound, (C7H10N)2(H3O)2[Fe(CN)6] or (Etpy)2(H3O)2[Fe(CN)6] (Etpy+ is 1-ethyl-pyridinium), crystallizes in the space group Pnnm. The FeII atom of the [Fe(CN)6]4- anion lies on a site with site symmetry ..2/m, and has an octa-hedral coordination sphere defined by six cyanido ligands. Both the Etpy+ and the oxonium cations are located on a mirror plane. In the crystal, electron-donor a...

A new phenyl-triazole-pyrazine ligand, 4-p-tolyl-3-(phenyl)-5-(2-pyrazinyl)-1,2,4-triazole (tolpzph), was prepared in order to enforce pyrazine coordination of the iron(ii) centre in the resulting complex, [FeII(tolpzph)2(NCS)2]·THF (1·THF). Structure determinations carried out on this discrete mononuclear complex, 1·THF, at 273 K (mostly high spin) and 100 K (mostly low spin) demonstrate this ...

We present a large sample of Hand K-band spectra of 32 optically line-luminous central cluster galaxies. We find significant rovibrational H2 emission in 23 of these galaxies as well as H recombination and/or [FeII] emission in another 5. This represents a fourfold increase in the number of molecular line detections known. A number of the detections are of extended emission (5–20 kpc). In sever...

Ribonucleotide reductases (RNRs) convert nucleotides to deoxynucleotides in all organisms. Activity of the class Ia and Ib RNRs requires a stable tyrosyl radical (Yⁱ), which can be generated by the reaction of O2 with a diferrous cluster on the β subunit to form active diferric-Yⁱ cofactor. Recent experiments have demonstrated, however, that in vivo the class Ib RNR contains an active dimangane...

We report direct electrochemistry of the iNOS heme domain in a DDAB film on the surface of a basal plane graphite electrode. Cyclic voltammetry reveals FeIII/II and FeII/I couples at -191 and -1049 mV (vs Ag/AgCl). Imidazole and carbon monoxide in solution shift the FeIII/II potential by +20 and +62 mV, while the addition of dioxygen results in large catalytic waves at the onset of FeIII reduct...