The first suberato-bridged lanthanide coordination polymer:: synthesis, crystal structure and properties of La2(H2O)2L3 (H2L = HOOC(CH2)6COOH)

Reaction of suberic acid (H2L = HOOC(CH2)(6)COOH), LaCl3 and NaOH at 170 degrees C yielded La-2(H2O)(2)L-3. The complex is triclinic, space group P (1) over bar, with a = 8.246(1), b = 13.463(2), c 14.073(2) angstrom, alpha = 104.29(1)degrees, beta 105.07(1)degrees, gamma = 93.61(1)degrees, Z = 2, V = 1448.4(3) angstrom(3), R-1 = 0.0324 and wR(2) = 0.0723 for 5319 observed reflections (I >= 2 sigma(I)) of 6597 unique reflections. The crystal structure features infinite lanthanum oxide chains of edge-sharing (LaO9) mono-capped square antiprisms, in which La atoms are coordinated by nine oxygen atoms of six suberate anions and one water molecule at the cap with d(La-O) = 2.475-2.666 angstrom. The chains are bridged by the dicarboxylate anions to form a 3D, nonporous framework and interchain hydrogen bonding interactions between the capping water and carboxylate oxygen atoms contribute to the stabilization of the crystal structure. Thermogravimetric and IR properties are presented.