Binary compounds of silicon are binary chemical compounds containing silicon and one other chemical element. Technically the term silicide is reserved for any compounds containing silicon bonded to a more electropositive element. Binary silicon compounds can be grouped into several classes. Saltlike silicides are formed with the electropositive s-block metals. Covalent silicides and silicon compounds occur with hydrogen and the elements in groups 10 to 17. Transition metals form metallic silicides, with the exceptions of silver, gold and the group 12 elements. The general composition is MnSi or MSin with n ranging from 1 to 6 and M standing for metal. Examples are M5Si, M3Si (Cu, V, Cr, Mo, Mn, Fe, Pt, U), M2Si (Zr, Hf, Ta, Ir, Ru, Rh, Co, Ni, Ce), M3Si2 (Hf, Th, U), MSi (Ti, Zr, Hf, Fe, Ce, Th, Pu) and MSi2 (Ti, V, Nb, Ta, Cr, Mo, W, Re). The Kopp–Neumann law applies as: Cp(M,Si,) = xCp(M) + yCp(Si) As a general rule, nonstochiometry implies instability. These intermetallics are in general resistant to hydrolysis, brittle, and melt at a lower temperature than the corresponding carbides or borides. They are electrical conductors. However, some, such as CrSi2, Mg2Si, β-FeSi2 and MnSi1.7, are semiconductors. Since degenerate semiconductors exhibit some metallic properties, such as luster and electrical conductivity which decreases with temperature, some silicides classified as metals may be semiconductors. (en)
Binary compounds of silicon are binary chemical compounds containing silicon and one other chemical element. Technically the term silicide is reserved for any compounds containing silicon bonded to a more electropositive element. Binary silicon compounds can be grouped into several classes. Saltlike silicides are formed with the electropositive s-block metals. Covalent silicides and silicon compounds occur with hydrogen and the elements in groups 10 to 17. The Kopp–Neumann law applies as: Cp(M,Si,) = xCp(M) + yCp(Si) (en)