Bonding covalent bond classification

M. L. H. Green, J. Organomet. Chem. 500 (1983), 127. The Green method is also called the Covalent-Bond-Classification (CBC) method. 

Nitrides can be sub-divided into ionic, covalent and interstitial types.An alternate general classification of nitrides, based on bonding classification, as ionic, covalent and metallic has also been applied. Ionic or salt-like nitrides are formed by electropositive elements such as Li, Mg, Ca, Sr, Ba, Cu, Zn, Cd and Hg and possess formulae which correspond to those expected on the basis of the combination of the metal ion with ions. A range of covalent nitrides are known and are exhibited by less electropositive elements such as B, S, P, C and Si. Interstitial nitrides are formed by some transition metals and refer to compounds which can be described in terms of the occupancy of interstitial sites in close packed metallic structures by nitrogen atoms. Oxygen can also be accommodated within these structures and a range of oxynitrides are known to... 

CBC method, see Covalent bond classification method -bridged complexes... 

Covalent bond classification method, organotransition metal compounds ([Pg.87]

Covalent bond classification and elementary bonding concepts... 

Figure 1 Classification and examples of L, X, and Z ligands according to the Covalent Bond Classification method...

The Covalent Bond Classification (CBC) Method is an insightful approach specifically designed for covalent molecules and is particularly applicable to organometallic compounds. The conceptual core of the CBC method is to classify each ligand as a neutral species on the basis of its orbital interactions with the metal. This classification requires considering three fundamental interactions, represented by the symbols L, X, and Z... 

FIGURE 13.52 Covalent Bond Classification of Iron Complexes. 

Covalent Bond Classification Method 523 TABLE 13.9 Information Available from the Equivalent Neutral Class Formula... 

Use the Covalent Bond Classification Method to classify these complexes with a [ML/X ZJ formula. With charged species, reduce the formula to its equivalent neutral class. 

Use the Covalent Bond Classification Method to classify these hypothesized complexes with a [ML/X ] formula. With charged species, reduce the formula to its equivalent neutral class. On the basis on the MLX plot for iron in Section 13.7, speculate on the likelihood that the following iron complexes have been prepared. 

The Covalent Bond Classification Method and MLX plots are now introduced in Chapter 13. 

The ML/XxZz Covalent Bond Classification of Organotransition Metal Compounds 22... 

In the case of metal phosphides and some complexes involving metallic or metaUoidal p-block elements where the bonding may be other than covalent, this classification is not, of course, appropriate. 

The hydrides of the later main-group elements present few problems of classification and are best discussed during the detailed treatment of the individual elements. Many of these hydrides are covalent, molecular species, though association via H bonding sometimes occurs, as already noted (p. 53). Catenation flourishes in Group 14 and the complexities of the boron hydrides merit special attention (p. 151). The hydrides of aluminium, gallium, zinc (and beryllium) tend to be more extensively associated via M-H-M bonds, but their characterization and detailed structural elucidation has proved extremely difficult. 

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