Germanium atoms

The central germanium atom has one unshared pair and two bonds. 

B. Double Bond Systems Containing a Germanium Atom. 140 

Which orbitals are filled, and which set of orbitals is partially filled, in a germanium atom  

Compounds containing double-bonded silicon and germanium atoms are the nearest analogues of olefins, ketones and thioketones. However, most of them are very unstable and highly reactive species. 

Unstable compounds with double-bonded silicon and germanium atoms 

The structures of five germanimines have been examined by X-ray crystallography (entries 6-9, Table I). In each case, the germanium atom 

Matrix Infrared Spectroscopy of Intermediates with Low Coordinated Carbon, Silicon and Germanium Atoms 

One doubly bidentate Lewis base 2,2 -bipyrimidine is coordinated with one germanium atom, while in the case of the analogous lead compound coordination takes place with two lead atoms. 

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