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Magnetic susceptibility data have been measured in the temperature range 1.75 to 60 K for the following structurally characterized, single chloride-bridged copper(l1) chain compounds : dichlorobis(dimethy1 sulphoxide)copper( II), dichlorobis(imidazole)copper(ll), aquo(caffeine)dichlorocopper(ll), and dichloro[2-(2'-methylaminoethyl)pyridine]copper(ii). The first two compounds exhibit antiferromagnetic intrachain interactions with exchange coupling constants of -6.1 and -2.1 cm--l, respectively, while the second two compounds exhibit ferromagnetic interactions with J values of 0.48 and 1.58 cm-respectively. Except for dichlorobis(imidazole)copper(ii), which undergoes long-range magnetic ordering below 7.7 K, the exchange coupling constants become more negative as the angle a t the chloride bridge increases from 1 13.6" in dichloro[2-(2'-methylaminoethyl)pyridine]copper(l1) to 144.6' in dichlorobis(dimethy1 sulphoxide)copper(ll).