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Published on: December 4, 2016
Aqua-dipicrato(tetra-ethyl-ene glycol)gadolinium(III) picrate methanol hemisolvate
Abstract:
THE ASYMMETRIC UNIT OF THE TITLE COMPOUND [SYSTEMATIC NAME: aqua-bis(2,4,6-trinitro-phenolato)(3,6,9-trioxaundecane-1,11-diol)gadolinium(III) 2,4,6-trinitro-phenolate methanol hemi-solvate], [Gd(C(6)H(2)N(3)O(7))(2)(C(8)H(18)O(5))(H(2)O)](C(6)H(2)N(3)O(7))·0.5CH(4)O, contains two crystallographically independent Gd(III) complex cations with two uncoordinated picrate anions and one methanol mol-ecule. Each Gd(III) atom has nine coordination sites occupied by five O atoms of tetra-ethyl-ene glycol as a penta-dentate ligand, one O atom of a water mol-ecule and three O atoms of the two picrate anions as bidentate and monodentate ligands. The geometry is distorted tricapped trigonal prismatic. The mean planes of the two coordinated mono- and bidentate picrate ligands to the Gd(III) center are almost perpendicular to each other, as indicated by the dihedral angles of 89.92 (8) and 86.60 (8)° in the two complex cations. The ions are arranged in a two-dimensional network parallel to the ac plane. Short O⋯O and N⋯O contacts between the nitro groups, intra-molecular C-H⋯O hydrogen bonds, inter-molecular O-H⋯O, O-H⋯N and C-H⋯O hydrogen bonds, and two π-π inter-actions between benzene rings [centroid-centroid distances = 3.8073 (10)-3.9831 (10) Å] are observed. The methanol solvent mol-ecule is disordered over two positions, with site-occupancy factors of ca 0.6 and 0.4.

