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Published on: May 29, 2018
Pressure Dependence Investigation of the Low-Temperature Structure of TlAu(CN)(2) by High-Resolution Neutron Powder
Peter Fischer1, Joël Mesot, Brian Lucas
1Laboratory for Neutron Scattering, ETH Zurich & Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland, Department of Physics, The University of Queensland, Brisbane, Queensland 4072, Australia, Institut für anorganische, analytische und physikalische Chemie, Universität Bern, CH-3000 Bern, Switzerland, Department of Chemistry, University of Maine, Orono, Maine 04469, and Institut Laue-Langevin, BP 156, F-38042 Grenoble Cédex 9, France.
Abstract:
In contrast to the anomalous increase of the lattice parameter b and associated reorientation of the [Au(3)(CN)(2)](-) ion with decreasing temperature, the unit cell volume and the lattice parameters of TlAu(CN)(2) are found to decrease (at T = 62 K) linearly for external hydrostatic pressures up to 4.5 kbar. The [Au(CN)(2)](-) ions do not essentially change orientation with pressure. The structural results suggest that the change in luminescence energy with pressure is due to changes in Tl.Au as well as in Au.Au interatomic separations, which again illustrates the importance of Tl.Au covalent interactions in this compound.
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