Electron-Poor Hypoelectronic Metal Carbonyl Clusters

Electron-Poor (Hypoelectronic) Metal Carbonyl Clusters 

The following properties of tetrahedral chambers in capped deltahedra are significant  

Tetrahedral chambers in capped deltahedra require localized bonding like isolated tetrahedra. Tetrahedral chambers formed by capping deltahedra having all vertices of degree 3 may be regarded as islands of localization in an otherwise delocalized system. 

The capping vertex contributes the usual number of skeletal electrons but no skeletal orbitals. Therefore, capping is a good remedy for electron poverty.  

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