[Ni(1,10-phenanthroline)2(H2O)2](NO3)2: A Simple Coordination Complex with a Remarkably Complicated Structure that Simplifies on Heating

Crystals

Timothy J. Prior²  Apinpus Rujiwatra¹ 

[1] Department of Chemistry and Centre for Innovation in Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; E-Mail:;Department of Chemistry, University of Hull, Cottingham Road, Hull, HU6 7RX, UK

关键词: hydrogen bond;    supramolecular assembly;    single crystal structure;    nickel;    1;    10-phenanthroline;    nitrate;    polymorphism;   

DOI  :  10.3390/cryst1030178

来源: mdpi

【 摘 要 】

Despite the simple chemical formula, [Ni(1,10-phenanthroline)₂(H₂O)₂](NO₃)₂, crystallizes with a remarkably complicated 3-D hydrogen bonding supramolecular assembly. The title compound crystallizes in the monoclinic space group P2₁/c, with an unusually long b axis and a large cell volume. A huge asymmetric unit has been identified, containing six discrete [Ni(1,10-phen)₂(H₂O)₂]²⁺ cations and twelve nitrate anions. Detailed analyses of the crystal structure and O-H⋯O and C-H⋯O hydrogen bonding interactions are reported and discussed. In this way the anion-directed assembly of the 3-D structure is illustrated. The thermal and spectroscopic properties of the compound are described. Upon heating to 308 K, the crystal undergoes a phase change to a much simpler structure with a single [Ni(1,10-phen)₂(H₂O)₂]²⁺ cation within the asymmetric unit and unit cell volume one sixth of that at low temperature. Although the crystal decomposed during data collection, it was possible to establish the molecular packing in the high temperature form and relate it to that at low temperature.

【 授权许可】

CC BY   
© 2011 by the authors; licensee MDPI, Basel, Switzerland.