Magnetic coupling in a hybrid Mn(ii) acetylene dicarboxylate.

The design of ligands that mediate through-bond long range super-exchange in metal-organic hybrid materials would expand chemical space beyond the commonly observed short range, low temperature magnetic ordering. Here we examine acetylene dicarboxylate as a potential ligand that could install long range magnetic ordering due to its spatially continuous frontier orbitals. Using a known Mn(ii)-containing coordination polymer we compute and measure the electronic structure and magnetic ordering. In this case, the latter is weak owing to the sub-optimal ligand coordination geometry, with a critical temperature of 2.5 K.