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  • Crystal structures, phase transition, and Hirshfeld surface analyses of the bromide and chloride congeners of aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) halide
Title: Crystal structures, phase transition, and Hirshfeld surface analyses of the bromide and chloride congeners of aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) halide
During the course of exploring crystallization conditions in generating metal–organic frameworks (MOFs) for use in the crystalline sponge method, two discrete metal–organic complexes, namely, aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) bromide, [Zn(C18H12N6)(H2O)]Br2, and aqua[2,4,6-tris(pyridin-4-yl)-1,3,5-triazine]zinc(II) chloride, [Zn(C18H12N6)(H2O)]Cl2, were encountered. Structures in the orthorhombic space groupPnma(No. 62) for the bromide congener at 299 K and the chloride congener at 100 K were obtained. A phase transition for the bromide congener occurred upon cooling from 299 to 100 K, yielding a crystal polymorph with four domains that exhibits monoclinicP21/mspace-group symmetry (No. 11), which arises from conformational changes. The main intramolecular contacts that contribute to the crystal packing in all observed structures are H...H, Halide...H/H...Halide, C...H/H...C, and N...H/H...N. Intramolecular hydrogen bonding between the Zn-bound water and non-Zn-bound pyridyl N atoms is a prominent feature within the three-dimensional networks. Aromatic π-stacking between the non-Zn-bound pyridine rings and contacts involving the halide ligands further stabilize the crystal packing.  more » « less
Award ID(s):
2117502
PAR ID:
10560856
Author(s) / Creator(s):
; ;
Publisher / Repository:
International Union of Crystallography
Date Published:
Journal Name:
Acta Crystallographica Section C Structural Chemistry
Volume:
80
Issue:
9
ISSN:
2053-2296
Page Range / eLocation ID:
545 to 552
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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