Four-coordinated metal centers

Dinuclear anions, halogenocuprate(I) and halo-genoargentate(I) ions four-coordinated metal centers, 37 20-21 three-coordinated metal centers, 37 8-9, 12-16... 

Formic acid irradiation of, 3 183 reaction with hydrogen atom, 3 191 Formylium cation, 9 231 Formylmethanofuran dehydrogenase, Methano-bacterium wolfei, 40 73 Fossil fuel, radiocarbon and, 3 311-312 Four-coordinated metal centers, 37 19 Fourier-transform infrared spectroscopy, NiFe hydrogenase, 47 295-298, 299, 303 Fourier-transform ion cyclotron resonance... 

Polymeric anions, four-coordinated metal centers, halogenocuprate(I) and halogenoar-gentate(I) ions, 37 26-32 miscellaneous, 37 31-32... 

C. Species Containing Four-Coordinated Metal Centers... 

Fig. 9. Tetranuclear [M4X8]4 clusters containing (a) three- and four-coordinated metal(I) centers and (b) solely four-coordinated metal centers.

Selected Distances (A) in [M4X8]4 Clusters Containing Three- and Four-Coordinated Metal Centers 1... 

The dinuclear [Ag(Tp)]2, [Ag(Tp )]2, [Ag(pzTp)]2, (but also [Ag(TpMe)]2 and [Ag(Tp4"Br)]2) have been synthesized and characterized by IR, far-IR, NMR (1H and 13C), and FAB MS spectroscopy, and their interaction toward unidentate or bidentate N- or S-donor ligands was investigated.553 [Ag(Tp )]2 is an asymmetric dimer, in which each Tp ligand bridges both metals by two pyrazolyl donors to one Ag(I) center and one to the other. Even if, at a first approximation, one Ag(I) can be considered four-coordinate and the other two-coordinate, two of the pyrazolyl donors around the four-coordinate metal centers are also involved in weak, asymmetric bridging interactions with the two-coordinate metal centers (Fig. 2.134).554... 

M is usually a six-coordinate metal and the resulting architecture is tridimensional with large channels, but four-coordinate metal centers have also been used. Thus, the planar [Ni(CN)4] module leads to the formation of a macrocyclic system, 132 (R = Me, Sn-O 2.149 A, Sn- -N 2.529 A) [304]. 

Established for the series rraras-[FeBrL(depe)2]+ + (L = CO, aryl and alkyl N=CR, Br"). Four-coordinate metal center. 

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