Comprising Silicon, Germanium, and Tin

UV-Vis spectrum tailed off into the visible region. However, no structural information based on X-ray crystallographic analysis has been reported for 15. 

The choice of the substituent R is critical for the cubane synthesis. For instance, the cyclotetragermane 7a bearing four tert-bu. y groups and four 

A single crystal of 19 has a 3-fold axis and belongs to the rhombohedral space group R3c. However, structural refinement was unsuccessful because of the disorder of the substituents. Preliminary results show the evident cubic structure of 19 Ge-Ge bond lengths of 2.534 A (average) and Ge-Ge-Ge bond angles of 90.0° (34). 

Thermolysis of hexakis (2,6-diethylphenyl)cyclotristannane (21) in naphthalene at 200-220°C gave red octakis(2,6-diethylphenyl)octastana-cubane (22) in 0.76% yield together with dark blue violet pentastanna- 

All cubanes composed of the higher row group 14 elements are colored from yellow to purple. The aryl-substituted silacubane 16 (6) is orange and 

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