Research Article: Poly[[tetra­aqua­di-μ4-oxalato-μ2-oxalato-dineo­dymium(III)] dihydrate]

Date Published: March 01, 2012

Publisher: International Union of Crystallography

Author(s): Gao-Juan Cao, Cheng Rong, Qing-lu Li, Wen-Jing Jiang.


The title compound, {[Nd2(C2O4)3(H2O)4]·2H2O}n, was synthesized hydro­thermally in the presence of bis­(carb­oxy­ethyl­germanium) sesquioxide. It is isostructural with the corresponding Pr compound [Yang et al. (2009). Acta Cryst. E65, m1152–m1153]. The Nd3+ cation is nine-coordinated and its coordination polyhedron can be described as a distorted tricapped trigonal prism. Two Nd3+ ions are connected by two O atoms from two oxalate ions to give a dinuclear Nd2 unit. The unit is further linked to four others via four oxalate ions yielding a layerparallel to (0-11). The linkages between the layers by neighbouring oxalate anions lead to a three-dimensional framework with channels along the c axis. The coordinating and free water mol­ecules are located in the channels and make contact with each other and the host framework by weak O—H⋯O hydrogen bonds.

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For the application of lanthanide compounds, see: Kido & Okamoto (2002 ▶). For background to lanthanide oxalates, see: Kahwa et al. (1984 ▶); Trombe & Jaud (2003 ▶); Wang et al. (2008 ▶). For the isostructural Pr compound, see: Yang et al. (2009 ▶).