Explain the following with suitable examples. 12-16 and 13-15 group compounds.

Explanation

Germanium and silicon are group -14 elements and have, therefore, a characteristic valence of four and form four bonds as in diamond. A large variety of solid sate materials have been prepared by combination of elements of group-13 and 15 or 12 and 16 to stimulate average valence of four as in Ge or Si. Typical of elements of group 13-15 compounds are InSb, AIP and GaAs. Gallium arsenide (GaAs) semiconductors have very fast response and have revolutionised the design of semiconductor devices. ZnS, CdS, CdSe and HgTe are examples of group 12-16 compounds. In these compounds, the bonds are not perfectly covalent and the oinicity depends on the electronegativities of the two elements.