Preparation and gas adsorption studies of three mesh-adjustable molecular sieves with a common structure.

Solvothermal reactions of a predesigned amphiphilic ligand, 4'-tert-butyl-biphenyl-3,5-dicarboxylate (BBPDC), with Zn(NO(3))(2), Co(NO(3))(2), and Cu(NO(3))(2) gave rise to three isostructural mesh-adjustable molecular sieves (MAMSs), MAMS-2, MAMS-3, and MAMS-4, respectively. The three new MAMSs all exhibit temperature-tuned molecular sieving effect. There exists a linear relationship between mesh size and temperature, D = D(0) + alphaT (D, mesh size at temperature T K; D(0), mesh size at 0 K; and alpha, constant). Constants D(0) and alpha are characteristics of a ligand in a certain structure, independent of the choice of metal. As a result, all of the three MAMSs based on the BBPDC ligand have a D(0) of 2.83 and an alpha of 0.0073.