A 1D coordination polymer built on asymmetric μ1,1,3-azide bridge: from unusual topology to magnetic properties and Cu(II)/Cu(I) redox reversibility

An azide-bridged Cu(II) one dimensional polymer was synthesized in a one pot reaction in the presence of ammonia. The refined crystal structure evidenced the unusual asymmetric [11,1,3 coordination mode of the azide ion leading to a {Cu(mu(1,1,3)-N-3)(mu(1)-N-3)(NH3)(0.8)(H2O)(1.2)}(n) chain The redox process of this complex was studied by cyclic voltammetry evidencing the Cu(II)/Cu(I) reversibility. Magnetic measurements were interpreted as a uniform antiferromagnetic chain (J = -15.2 cm(-1)) holding rather strong inter-chain exchange (zJ' = -2.8 cm(-1)). Multireference difference dedicated configuration interaction (DDCI) calculations confirmed the non-negligible intensity of inter-chain interactions and evidenced a strong influence of the type of coordinated solvent, NH3 or H2O, on the nature and magnitude of the magnetic exchange.