Enthalpy bond length and

The relationships between bond enthalpy, bond length and bond order which appear relatively simple in the case of a main group element such as carbon and its compounds, are more difficult to establish when the d-transition metal elements and their compounds are considered. Progress in establishing these relationships for metals is severely hindered by a lack of relevant thermochemical data. This paper reviews some of the more useful information that is available for diatomic molecules, for polynuclear binary carbonyls and for binuclear complexes of the d-transition elements. 

Just as we can define an average bond enthalpy, we can also define an average bond length for a number of common bonds (A TABLE 8.5). Of particular interest is the relationship, in any atom pair, among bond enthalpy, bond length, and number of bonds between the atoms. For example, we can use data in Tables 8.4 and 8.5 to compare the bond lengths and bond enthalpies of carbon-carbon single, double, and triple bonds ... 

Correlate bond order, bond strength (bond enthalpy), bond length, and magnetic properties with molecular orbital descriptions of molecules. (Section 9.8)... 

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