Carbonyls dynamic properties

Noskov, S.Y. Berneche, S. Roux, B., Control of ion selectivity in potassium channels by electrostatic and dynamic properties of carbonyl ligands, Nature 2001,431, 830-834. 

The dynamic properties of (/j5-Cp)2Fe2(CO)3[P(OPh)3] have been studied by n.m.r. Two processes occur cis-trans isomerism and scrambling of bridging and terminal carbonyl groups. It was found that both processes have the same rate and activation parameters within experimental error and this is in complete agreement with the mechanism proposed by Adams and Cotton and discussed earlier in this... 

A second set of conhibutions presents specific methodological and technical features of organometallic NMR applications to solids and to NMR under exceptional diemical and experimental conditions. The two chapters on solid state NMR deal with prospects of organometallic compounds focusing on stiuctural and dynamic properties of carbonyl metal complexes and organotin and -lead compounds. 

Structural and Dynamic Properties of /i-Dimethyl-germyl-//-carbonyl-dicy-clopentadienyldicarbonyldiiron, K. D. Adams, M. D. Brice, and F. A. Cotton, Inorg. Ghent., 13, 1080(1974). 

For [Fe3(CO)i2], considerable asymmetry of the bridging Fe —CO —Fe bonds is characteristic. In solutions, this trinuclear iron compound exhibits dynamic properties. The IR spectra show that the number of isomers with bridging carbonyl groups... 

The majority of metal carbonyl hydrides show dynamic properties, that is, stereochemical lability. The positions of atoms change with a noticeable rate (stereoisomerization). These properties are most often investigated by NMR. The nuclear magnetic resonance method may be used only if the stereoisomerization occurs fast enough to influence the line shape and simultaneously allow the interaction between nuclear spins. 

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