Subhalide

In chemistry, subhalide usually refers to inorganic compounds where the halide/metal ratio requires metal-metal (or element-element for nonmetals) bonding, sometimes extensively. Many compounds meet this definition.

Boron forms many subhalides, starting with B₂X₄, a representative member being diboron tetrafluoride. Aluminium forms a variety of subhalides. For gallium, adducts of Ga₂Cl₄ are known. Phosphorus subhalides include P₂I₄ P₄Cl₂, and P₇Cl₃ (structurally related to P₇³⁻). For bismuth, the compound originally described as bismuth monochloride was later shown to consists of Bi₉⁵⁺ clusters with chloride anions. Telluriium subhalides are particularly extensive and include the following members Te₃Cl₂, Te₂X (X = Cl, Br, I), and two forms of TeI.

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