metaalcyanide

Metaalcyanide, or metal cyanide, refers to compounds in which a metal center is bound to cyanide ligands (CN−). The category includes simple inorganic cyanides with formulas such as MCN or M(CN)n, as well as more complex cyanometalate species and extended cyanide networks in solids. In coordination chemistry, cyanide acts as a strong-field ligand, forming both discrete coordination compounds and polymeric lattices.

Notable examples include ferrocyanide [Fe(CN)6]4− and ferricyanide [Fe(CN)6]3−, which constitute a classic redox couple used in analytical chemistry and electrochemistry. Potassium ferrocyanide K4[Fe(CN)6] and potassium ferricyanide K3[Fe(CN)6] have historical and contemporary roles as reagents, reducing agents, and components in pigments. The iron-cyanide prussian blue family, such as Fe4[Fe(CN)6]3, is a well-known pigment with applications in art and materials science.

Metal cyanides vary in solubility: many simple cyanides of Cu, Zn, Ag, and other metals form insoluble solids, while many cyanometalate ions are water-soluble and highly stable in solution. Applications span mining and metallurgy, where cyanide complexes facilitate metal processing, to catalysis and materials chemistry, where cyanide-bridged networks underpin functional materials.

Safety and handling are essential, as cyanide compounds can be highly toxic. Proper safety protocols and waste management are required in any handling, synthesis, or application.