Other Compounds

Carbon disulfide CS₂ has related bonding to CO₂, but SiS₂ be different from silica in having a chain structure that is based on edge-sharing tetrahedra and GeS₂ accepts the CdI₂ layer structure with octahedral Ge. Nitrogen compounds involve the toxic species cyanogen (CN)₂ (2) and the cyanide ion CN^-, that forms strong complexes with several transition metals. Si₂N₂O and Si₃N₄ are polymeric compounds with single Si-N bonds, both forming refractory, chemically and hard resistant solids of interest in engineering applications.

Compounds with metals depict a great diversity. Some silicides and carbides of electropositive metals, like Al₃C₄ and Ca₂Si, could be formulated along with C^4- and Si^4- ions even though the bonding is surely not very ionic. Compounds through transition metals are metallic in character, those of Si and Ge being usually considered as intermetallic compounds, those of carbon like interstitial compounds with small carbon atoms taking place holes in the metal lattice. Some like TaC and WC are extremely hard, high melting and chemically unreactive, and are employed in cutting tools. Fe₃C take place in steel and contributes to the mechanical hardness. Several compounds with E-E bonding are well-known. CaC₂ has C₂ ^2- ions (isoelectronic with N₂) and responds with water to give ethyne C₂H₂. Alternatively, KSi and CaSi₂ are Zintl compounds with single-bonded structures. Ge (like Sn and Pb) creates some polyanions like [Ge₉]^4- . Organometallic compounds consisting of metal-carbon bonds are created through almost all metals, and are discussed under the appropriate elements. Some similar Si and Ge compounds are well-known.