What is "hexachlorocyclohexane"

n. (context chemistry English) A six-chlorine substituted cyclohexane, a polyhalogenated compound used in pesticides.

Hexachlorocyclohexane (HCH) is any of several polyhalogenated organic compounds consisting of a six-carbon ring with one chlorine and one hydrogen attached to each carbon. There are many isomers for this structure, differing by the stereochemistry of the individual chlorine substituents on the cyclohexane. It is sometimes called erroneously called " benzene hexachloride" (BHC). They have been used as models for analyzing the effects of different geometric positions of the large atoms with dipolar bonds on the stability of the cyclohexane conformation. Some isomers are pesticides.

Common forms are:

• α-HCH ( CAS RN: ), or α-BHC, alpha-hexachlorocyclohexane, the only isomer that is optically active
• β-HCH (CAS RN: ), or β-BHC, beta-hexachlorocyclohexane
• γ-HCH (CAS RN: ), or γ-BHC, gamma-hexachlorocyclohexane, or lindane
• δ-HCH (CAS RN: ), or δ-BHC, delta-hexachlorocyclohexane
• t-HCH (CAS RN: ), or t-BHC, technical hexachlorocyclohexane

--hexachlorocyclohexane.svg| α-hexachlorocyclohexane, the dextrorotatory enantiomer. | α-hexachlorocyclohexane, the levorotatory enantiomer. | β-hexachlorocyclohexane. | γ-hexachlorocyclohexane. | δ-hexachlorocyclohexane. | ε-hexachlorocyclohexane. | ζ-hexachlorocyclohexane. | η-hexachlorocyclohexane. | θ-hexachlorocyclohexane.