title: Crystal structure of ammonium bis-(pyridine-2,6-di-carboxyl-ato-κ(3) O,N,O')chromate(III) from synchrotron data.
abstract: The structure of the title compound, (NH4)[Cr(pydc)2] (pydc is pyridine-2,6-di-carboxyl-ate, C7H3NO4), has been determined from synchrotron data. The Cr(III) ion and the N atom of the ammonium cation are located on a crystallographic fourfold rotoinversion axis (-4). The Cr(III) cation is coordinated by four O atoms and the two N atoms of two meridional pydc ligands, displaying a distorted octa-hedral geometry. The Cr-N and Cr-O bond lengths are 1.9727 (15) and 1.9889 (9) Å, respectively. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the N-H groups of the ammonium cation and pyridine C-H groups as donors and the non-coordinating carbonyl O atoms as acceptors.
authors: Pohang Accelerator Laboratory, POSTECH, Pohang 790-784, Republic of Korea.
authors: Dohyun
authors: D
authors: Moon
authors: Department of Chemistry, Andong National University, Andong 760-749, Republic of Korea.
authors: Jong-Ha
authors: JH
authors: Choi
keywords: Crystal structure; ammonium cation; chromate(III) complex; hydrogen bonding; meridional configuration; pyridine-2,6-di­carboxyl­ate; synchrotron radiation