Tellurium—germanium bonds

Compounds with germanium bonded to sulfur, selenium, or tellurium 741... 

Divalent tellurium derivatives in which tellurium is bonded to two group IV elements, are known as linear and cyclic compounds. Symmetrical compounds with two silicon, germanium, tin, or lead atoms bonded to tellurium and unsymmetrical compounds, with two different group IV elements linked to tellurium have been prepared. Some of the compounds have an obnoxious odor4. 

Many elemental metalloid surfaces, on the other hand, are considered to have perturbed structure when clean. Examples are the (HI), (HO), and (100) faces of silicon and germanium 126a, 338), the (HI) and (100) faces of diamond 286, 287), the (1120) planes of bismuth and antimony 297), and the (1000) surface of tellurium 325). It is believed that the (HI) and (100) planes of GaAs have altered periodicities also 133, 339). Distortions of all these covalently bonded surfaces are explained by assuming configurations that partially satisfy the free valence of the strongly directional cut bonds. These structures are complex and not yet completely determined 340-344). 

Fig. 5.3 (color online) Crystal structure of semiclathrate-I. A unit cell content is shown. Te-filled dodecahedra, cyan tellurium, green germanium/phosphorus, magenta bonds within the framework, gray host-guest bonds, red... 

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