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Updated: Mar 16, 2026

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Crystal structure of ammonium/potassium trans-bis-(N-methyl-iminodi-acetato-κ(3) O,N,O')chromate(III) from
1Pohang Accelerator Laboratory, POSTECH, Pohang 37673, Republic of Korea.
Abstract:
The structure of the title compound, [(NH4)0.8K0.2][Cr(C5H7NO4)2] (C5H7NO4 is methyl-iminodi-acetate; mida), has been determined from synchrotron data. The Cr(III) atom is located on a centre of symmetry and is coordinated by two N atoms and four O atoms of two facially arranged tridentate mida ligands, displaying a slightly distorted octa-hedral coordination environment. The Cr-N and mean Cr-O bond lengths are 2.0792 (14) and 1.958 (14) Å, respectively. The cation site is located on a twofold rotation axis and shows occupational disorder, being occupied by ammonium and potassium cations in a 0.8:0.2 ratio. In the crystal, inter-molecular hydrogen bonds involving the N-H groups of the ammonium cation as donor and the two non-coordinating O atoms of the carboxyl-ate group as acceptor groups consolidate the three-dimensional packing.
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