CRYSTAL STRUCTURE OF A NEW BINUCLEAR COMPLEX bis(2,4,6,8-TETRAMETHYL-2,4,6,8-TETRAAZABICYCLO(3.3.0) OCTANE-3,7-DIONE-O, O')-TETRAAQUA-hexakis(NITRATO-O,O')-DIEUROPIUM(III)

摘要

A centrosymmetric binuclear complex of europium(III) nitrate with bicyclic bisurea (2,4,6,8-tetramethyl 2,4,6,8-tetraazabicyclo(3.3.0)octane-3,7-dione, or mebicar, Mk) [Eu(C8H14N4O2)(H2O)(2)(NO3)(3)](2) (I) is synthesized and its atomic structure (CIF file CCDC No. 1451437) is determined. The crystals of I are triclinic: space group P (1) over bar, a = 9.8343(4) angstrom, b = 10.2544(4) angstrom, c = 10.9411(4) angstrom, alpha = 74.366(3)degrees, beta = 67.734(4)degrees, gamma = 67.673(4)degrees, V= 934.32(7)angstrom(3), p(calc.) = 2.03398 g/cm(3), Z= 1. The europium atom is coordinated by two oxygen atoms of two Mk molecules connected by a symmetry operation, three bidentate nitrate anions, and two water molecules. The coordination polyhedron of the europium atom is a 10-vertex polyhedron, the Eu...Eu distance is 9.7433(6) angstrom.