Metal-carbon bond lengths

Ethylidyne (CCH3) is adsorbed in 3-fold fee sites LEED (12) with a 1.30 0.05-A metal-terminal-carbon distance. The C—C axis is perpendicular to the surface with a 1.45 0.05-A bond length. CO molecules are adsorbed perpendicular to the surface in 3-fold hep sites, carbon atom down, with a carbon-metal bond length of 1.30 ... 

The osmium-carbyne carbon bond lengths for the three complexes do not differ significantly, and reference to Table IV indicates that these distances are distinctly shorter than the characterized metal-carbon double bonds of osmium carbene and carbonyl complexes. In both osmium alkylidene and carbyne complexes, then, the metal-carbon multiple bond lengths are largely insensitive to changes in the metal electron density (cf. Section IV,B). 

Metal Metal-carbon (A) Bond length Metal-oxygen (A)... 

The carbon—oxygen bond length in the free CO molecule is 1.128 A and in CO 1.171 A. In terminal metal carbonyls the C—0 distances lie between 1.14 and 1.16 A, the slight lengthening compared with free CO being consistent with the reduction in bond order which occurs on complexing. This increase is so small,... 

Experimental evidence supports the resonance description of the carbonate ion. X-ray diffraction data (Chapter 4) of metal carbonate crystals reveals that all the carbon-oxygen bond lengths in this ion are equivalent, and are shorter than a single C-0 bond but slightly longer than a C=0 bond. 

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