Soleimannejad Janet, Derikvand Zohreh, Koleiae Farzaneh
School of Chemistry, College of Science, University of Tehran, Tehran, Iran.
Department of Chemistry, Faculty of Sciences, Khorramabad Branch, Islamic Azad University, Khorramabad, Iran.
Acta Crystallogr C Struct Chem. 2014 Jun;70(Pt 6):613-6. doi: 10.1107/S2053229614009668. Epub 2014 May 23.
A three-dimensional coordination polymer of Sr(II) based on dipicolinic acid (pydcH2) has been synthesized and characterized, namely poly[[diaquabis(μ3-6-carboxypyridine-2-carboxylato)bis(μ4-pyridine-2,6-dicarboxylato)tristrontium(II)] dihydrate], {[Sr3(C7H3NO4)2(C7H4NO4)2(H2O)2]·2H2O}n. The asymmetric unit consists of two unique Sr(II) centres (one of them situated on an inversion centre), two independent pydc(2-) ligands, and one coordinated and one uncoordinated water molecule. The two independent Sr(II) cations are surrounded by water and dipicolinate molecules in distorted square-antiprism and distorted tricapped trigonal prismatic geometries. The dipicolinate ligands adopt μ3- and μ4-bridging modes, linking the alkaline earth metal centres into a three-dimensional coordination framework. One dipicolinate ligand is doubly deprotonated, while the other is singly deprotonated.
