Comparative study of two layered lanthanide dicarboxylates based on europium(III) dimers

摘要

The new rare-earth dicarboxylate solid Eu_2(H_2O)_4{C_6H_(10)-(CO_2)_2}3centre dot 2H_2O or MIL-94 has been isolated under hydrothermal conditions. Its layered structure, which was solved using X-ray powder diffraction data, is built up from dimers of nine-coordinated edge-sharing polyhedra linked through 1,3-cyclohexane dicarboxylate (1,3-CHC) moieties. A comparative study of MIL-94 and the layered lanthanide dicarboxylate EuBDC or Eu2(H_2O)_2{C_6H_4-(CO_2)_2}_3, which is built up from dimers of corner-sharing polyhedra and 1,3-benzenedicarboxylate (1,3-BDC) linkers, is also reported. Crystal data for MIL-94: orthorhombic space group Pnma (no. 62) with a = 8.8470(1) A, b = 25.0148(1) A, c = 14.3716(4) A and Z = 4. MIL stands for Material Institut Lavoisier.