Magneto-structural correlations in a family of ReCu chains based on the hexachlororhenate(iv) metalloligand.

Six novel one-dimensional chloro-bridged ReCu complexes of formula {[Cu(L)][ReCl]}, where L = imidazole (Imi, 1), 1-methylimidazole (Meim, 2), 1-vinylimidazole (Vim, 3), 1-butylimidazole (Buim, 4), 1-vinyl-1,2,4-triazole (Vtri, 5) and N,N'-dimethylformamide (DMF, 6) are characterised structurally, magnetically and theoretically. The structures exhibit significant differences in Cu-Cl bond lengths and Re-Cl-Cu bridging angles, resulting in large differences in the nature and magnitude of magnetic exchange interactions between the Re and Cu ions. Theoretical calculations reveal the coupling to be primarily ferromagnetic, increasing in magnitude as the bridging angle becomes smaller and the bond lengths shorten.