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Hexachlorocyclohexane -LRB- HCH -RRB- is any of several polyhalogenated organic compounds consisting of a six-carbon ring with one chlorine and one hydrogen attached to each carbon .. polyhalogenated. polyhalogenated compound. six-carbon ring. cyclohexane. chlorine. chlorine. hydrogen. hydrogen. There are many isomers for this structure , differing by the stereochemistry of the individual chlorine substituents on the cyclohexane .. chlorine. chlorine. stereochemistry. stereochemistry. cyclohexane. cyclohexane. It is sometimes called erroneously called `` benzene hexachloride '' -LRB- BHC -RRB- .. benzene hexachloride. benzene hexachloride ( disambiguation ). 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 .. cyclohexane. cyclohexane. cyclohexane conformation. cyclohexane conformation. Some isomers are pesticides. Common forms are  :. α-HCH -LRB- CAS RN  : -RRB- , or α-BHC , alpha-hexachlorocyclohexane , the only isomer that is optically active. isomer. isomer. CAS RN. CAS registry number. alpha-hexachlorocyclohexane. alpha-hexachlorocyclohexane. optically active. optically active. β-HCH -LRB- CAS RN  : -RRB- , or β-BHC , beta-hexachlorocyclohexane. CAS RN. CAS registry number. beta-hexachlorocyclohexane. beta-hexachlorocyclohexane. γ-HCH -LRB- CAS RN  : -RRB- , or γ-BHC , gamma-hexachlorocyclohexane , or lindane. CAS RN. CAS registry number. lindane. lindane. δ-HCH -LRB- CAS RN  : -RRB- , or δ-BHC , delta-hexachlorocyclohexane. CAS RN. CAS registry number. t-HCH -LRB- CAS RN  : -RRB- , or t-BHC , technical hexachlorocyclohexane. CAS RN. CAS registry number