SQUEEZE for treating severely disordered solvent molecules in the refinement of the otherwise ordered crystal structures of [Cd(C12H10N4)(C15H9O2)2(CH3OH)]·0.5H2O·CH3OH and [Cd(C12H10N4)1.5(C15H9O2)2]·CH3OH

Seik Weng Ng


In the refinement of the crystal structure of [Cd(C12H10N4)(C15H9O2)2(CH3OH)].0.5H2O.CH3OH, the lattice water molecule was not located by difference Fourier synthesis but was instead deduced by using SQUEEZE owing to severe disorder of the water molecule in the otherwise ordered crystal structure.  Similarly deduced were the two symmetry-independent methanol molecules in [Cd(C12H10N4)1.5(C15H9O2)2].CH3OH.  The first coordination polymer adopts a chain motif and the second a layer motif; for both, the N-heterocycle functions as a bridge to connect adjacent metal atoms.  The solvent molecules are presumed to reside in voids, which are themselves connected into channels.  The crystallographic program Crystal Explorer was used in the illustration of the channels.  Crystal data C44H37N4O6.5Cd: FW = 838.18, monoclinic, P21/n, a = 16.7871(4) Å, b = 26.5431(5) Å, c = 18.7034(5) Å, b = 111.915(3)°, V = 7731.7(3) Å3.  Crystal data for C49H38N6O5.5Cd: FW = 911.25, monoclinic, P21/c, a = 11.0586(3) Å, b = 23.5007(6) Å, c = 17.3454(5) Å, b = 105.626(3)°, V = 4341.2(2) Å3.


solvent molecules, voids, SQUEEZE, Crystal Explorer

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DOI: http://dx.doi.org/10.20450/mjcce.2015.628


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