Organization of Mn-Clusters in <i>pcu</i> and <i>bcu</i> Networks: Synthesis, Structure, and Properties

Abstract

Two new anionic inorganic–organic hybrid compounds [H 3 O][Mn 3 (μ 3 -OH)(C 14 H 8 O 6 S) 3 (H 2 O)](DMF) 5, I, and [H 3 O] 2 [Mn 7 (μ 3 -OH) 4 (C 14 H 8 O 6 S) 6 (H 2 O) 4 ](H 2 O) 2 (DMF) 8, II, have been prepared by employing mild solvothermal methods. Both the compounds have three-dimensionally extended structures formed by Mn 6 and Mn 7 clusters, respectively. The connectivity between Mn 6 and Mn 7 clusters and 4,4′-sulfonyldibenzoic acid anions (SDBA 2– ) results in a six connected pcu network in I and an eight connected bcu network in II . The presence of hydronium ion (H 3 O + ) along with the solvent molecules in the channels of both the compounds suggested proton conduction in the solids. Proton conductivity studies gave values of ∼3 × 10 –4 Ω –1 cm –1 98% relative humidity in both the compounds. The high activation energies indicate a vehicle mechanism in the compounds I and II . Magnetic studies indicate antiferromagnetic behavior in both the compounds.