Two halide exchange in copper(II) halide dimers: (Morpholinium)2Cu2ClxBr6 − x

Hydrogen bonding forces short halide⋯halide contacts of ∼4 Å between otherwise structurally isolated copper(II) dimers in the (morpholinium)2Cu2ClxBr6 − x salts. This contacts provide an efficient magnetic exchange pathway between dimers, so that the systems behave as alternating antiferromagnetic chains. The strength of this halide⋯halide coupling is approximately seven times as large in the bromide salt as in the chloride salt.