eCite Digital Repository

Cooperative Jahn-Teller Interactions in dynamic copper(II) complexes. Temperature dependence of the crystal structure and EPR spectrum of deuterated ammonium copper(II) sulfate hexahydrate

Citation

Hitchman, MA and Maaskant, W and van der Plas, J and Simmons, CJ and Stratemeier, H, Cooperative Jahn-Teller Interactions in dynamic copper(II) complexes. Temperature dependence of the crystal structure and EPR spectrum of deuterated ammonium copper(II) sulfate hexahydrate, Journal of the American Chemical Society, 121, (7) pp. 1488-1501. ISSN 0002-7863 (1999) [Refereed Article]

DOI: doi:10.1021/ja981831w

Abstract

The crystal structure of the deuterated Tutton salt (ND 4) 2[Cu(D 2O) 6](SO 4) 2 determined by X-ray diffraction at several temperatures between 100 and 321 K is reported. The intermediate and longest Cu-O bond lengths of the Jahn-Teller distorted octahedral Cu(D 2O) 6 2+ ion progressively converge as the temperature is raised above ~200 K, and this is accompanied by a partial rotation of the ammonium and sulfate groups. The g-values derived from the EPR spectrum of the compound exhibit similar behavior, as do those of ~1% Cu 2+ doped into the isomorphous zinc(II) compound. The temperature dependence of the g-values of Cu 2+doped (ND 4) 2[Zn(D 2O) 6](SO 4) 2 may be interpreted satisfactorily by a model which assumes a Boltzmann thermal distribution between two energy states which differ solely in the orientation of the Cu(D 2O) 6 2+ ion in the lattice. However, such a model does not Satisfactorily explain the behavior of pure (ND 4) 2[Cu(D 2O) 6](SO 4) 2, and it is suggested that this is due to cooperative interactions. A new model, in which the probable energy state of each complex is estimated after taking into account the likely orientations of its neighbors in the lattice, is described. Application of this model suggests that the thermal behavior is dominated by the cooperative interactions between complexes, these being transmitted via the hydrogen- bonding network. Comparisons are drawn with the cooperative interactions observed in more strongly coupled Jahn-Teller systems and in compounds for which the structural changes are associated with equilibria between two spin states.

Item Details

Item Type:Refereed Article
Research Division:Chemical Sciences
Research Group:Inorganic Chemistry
Research Field:Transition Metal Chemistry
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Chemical Sciences
Author:Hitchman, MA (Dr Michael Hitchman)
Author:Stratemeier, H (Dr Horst Stratemeier)
ID Code:16588
Year Published:1999
Web of Science® Times Cited:70
Deposited By:Chemistry
Deposited On:1999-08-01
Last Modified:2011-08-05
Downloads:0

Repository Staff Only: item control page