Bulk modulus and non-uniform compression of Nb3Te4 and InxNb3Te4 (x < 1) channel compounds

• Published in: Acta crystallographica. Section B, Structural science Structural science, 2001-10, Vol.57 (5), p.665-672
• Main Authors: Wunschel, Markus, Dinnebier, Robert E., Carlson, Stefan, Van Smaalen, Sander
• Format: Article
• Language: English
• Subjects: bulk modulus; channel compounds; compression; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Halides, chalcogenides and analogous compounds of group vb; High-pressure and shock-wave effects in solids and liquids; Inorganic compounds; Mechanical and acoustical properties of condensed matter; Physics; Structure of solids and liquids; crystallography; Structure of specific crystalline solids; X-ray powder diffraction
• ISSN: 0108-7681; 1600-5740
• DOI: 10.1107/S0108768101011685

The crystal structures of Nb3Te4 and InxNb3Te4 [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 InxNb3Te4 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 InxNb3Te4. 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.