Metal-organic frameworks of manganese(II) 4,4 '-biphenyldicarboxylates: crystal structures, hydrogen adsorption, and magnetism properties

Reactions of 4,4'-biphenyldicarboxylic acid (H(2)bpdc) with manganese(II) nitrate under solvothermal conditions yield two types of new metal-organic frameworks, [Mn-4(bpdc)(4)(DMF)(3)](DMF) (1) (DMF = N,N'-dimethylformamide) and Mn-3(bpdc)(3)(DMA)(4) (2) (DMA = N,N'-dimethylacetamide). Structural analysis shows different solvents lead to distinct phases of manganese(II) 4,4'-biphenyldicarboxylate although the same starting materials are employed. Complex 1 features a microporous noninterpenetrated structure with nano-sized channels and a rare cem topological net, while 2 is non-porous with an a-polonium topology. Microporous 1 exhibits significant hydrogen adsorptive capability. Magnetic behaviors of the both complexes suggest the presence of antiferromagnetic interactions.