Syntheses, Crystal Structures, and Magnetic Properties of Two Manganese(II) Coordination Polymers Based on Bifunctional Pyridine-benzene Carboxylic Acids
Two manganese(II) coordination polymers, namely, {[Mn(PIP)(BIBP)]center dot(BIBP)(0.5)}(n) (1) and {[Mn(PTA)(BIMBP)(H2O)]center dot H2O0.69}(n) (2) (H2PIP = 5-(4-pyridyl)-isophthalic acid, H(2)PTA = 6-(4-pyridyl)-terephthalic acid, BIBP = 4,4'-bis(imidazol-l-yl)biphenyl, and BIMBP = 4,4'-bis(imidazol-l-ylmethyl)biphenyl), have been synthesized by using the bifunctional pyrinde-benzene carboxylic acids and bis(imidazole) linkers as mixed ligands to react with MnSO4, and further characterized by elemental analysis, IR, and PXRD. Compound 1 is in the triclicnic system, space group P (1) over bar with a = 10.1089(8), b = 13.1927(12), c = 14.0638(12) angstrom, alpha = 69.437(2), beta = 73.2890(10), gamma = 78.5320(10)degrees, V = 1671.9(2) angstrom(3), Z = 2, D-c = 1.449 g/cm(3), F(000) = 705, mu(MoKa) = 0.453 mm(-1), S = 1.053, R= 0.0491 and wR = 0.1367 for 5837 unique reflections (R-int- = 0.0208) with I> 2 sigma(I). Compound 2 belongs to the monoclicnic system, space group C2/c with a = 15.199(3), b = 19.731(3), c = 21.537(5) angstrom, = 105.228(3)degrees, V = 6232(2) angstrom(3), Z = 8, D-c = 1.363 g/cm(3), F(000) = 2648, mu(MoKa) = 0.475 mm(-1), S = 1.048, R = 0.0489 and wR = 0.1151 for 7414 unique reflections (R-int = 0.0425) with I > 2 sigma(I). Structural analyses reveal that complex 1 is a 4 -connected (4(4).6(2))-sql bilayer structure with binuclear [Mn-2(COO)(2)] SBU, while complex 2 is a normally (3,5) -connected (4(2).6(7).8)(4(2).6)-3,5L2 monolayer. And the sheets interacted with the adjacent sheets through weak interactions, finally giving a stable three-dimensional (3D) supramolecule. Besides, the variable -temperature magnetic susceptibility measurement of complex 1 was investigated.