Manganese bonding parameters

A problem arose when the X-ray crystal structure of [Mn(CH3)(CO)5] was attempted (55). Results showed that the solid phase was almost entirely orientationally disordered each of the six coordination sites around the manganese atom was found to be occupied by, on average, about five-sixths of a carbonyl ligand and one-sixth of a methyl ligand. The superimposed methyl and carbonyl carbon atoms could not be resolved, which precluded determination of any significant bonding parameters. However, the X-ray diffraction data did indicate that [Mn(CH3)(CO)5] crystallizes in... 

HOMO of the molecular sulfide by a factor B, which measures the nature (symmetry and strength) of the metal-sulfur bond. It is now possible to understand why the heat of formation was an insufficient parameter, because it did not contain the same quantities as this B parameter. In the case of manganese, the agreement between the measured and the calculated is excellent. To be a good catalyst, the sulfide should have a HOMO filled with as many electrons as possible and be of l2f symmetry instead of eg. 

Table 3 Fractional coordinates (X,Y,Z) and isotropic (Biso) and anisotropic (Bii, S22, 33, 23. 5i3, B12) thermal parameters (A ) for the manganese and oxygen atoms constituting the Mn-O bond, obtained by single-crystal neutron diffraction for Cs[Mn(0H2)6](S04)2 6H2O at...

The reactions of Me3MMn(CO)5 (M = Si, Ge) with fluoro-olefins and fluoroacetylenes give a range of bonded alkyl- and alkenyl-manganese complexes for which the parameters shown in [23] to [27] are reported. 

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