Bulk modulus and non-uniform compression of Nb₃Te₄ and In_xNb₃Te₄ (x <1) channel compounds

Summary, in English

The crystal structures of Nb₃Te₄ and In_xNb₃Te₄ [x = 0.539 (4)] are reported for a series of pressures between 0 and 40 GPa. Both compounds crystallize in space group P6₃/m with a = b = 10.671 and c = 3.6468 Å for Nb₃Te₄, and a = b = 10.677 and c = 3.6566 Å for In_xNb₃Te₄ at ambient conditions. Phase transitions were not observed. High-pressure X-ray powder diffraction was measured using a diamond anvil cell and synchrotron radiation. Full Rietveld refinements provided the values of the lattice parameters and the values of the atomic coordinates at each pressure. The bulk modulus is found as K₀ = 70 (5) GPa for Nb₃Te₄ and as K₀ = 73 (4) GPa for In_xNb₃Te₄. The analysis of the pressure dependences of the detailed crystal structures shows that the compression along c involves the folding up of the quasi-one-dimensional zigzag chains of Nb. The compression perpendicular to c is entirely due to the reduction of the diameter of the channels. The presence of intercalated In atoms is found to have hardly any influence on the compression behaviour up to 40 GPa.

• Author: Markus Wunschel; Robert E. Dinnebier; Stefan Carlson; Sander Van Smaalen
• Publishing year: 2001-10
• Language: English
• Pages: 665-672
• Publication/Series: Acta Crystallographica. Section B: Structural Science
• Volume: 57
• Issue: 5
• Links: http://dx.doi.org/10.1107/S0108768101011685
• Document type: Journal article
• Publisher: Wiley-Blackwell
• Status: Published
• ISBN/ISSN/Other: ISSN: 0108-7681