• Differing pressure response of lattice structure in LaTMSb$_2$ (TM = Au or Ag) ternary antimonides

• Fulltext

https://www.ias.ac.in/article/fulltext/boms/045/0189

• Keywords

Ternary antimonides; charge density wave; synchrotron powder XRD; hydrostatic high pressure; Raman.

• Abstract

Ternary antimonides LaTMSb$_2$ (TM = Au or Ag) share identical lattice symmetry and exhibit the charge density wave (CDW) phenomenon. The CDW is found to be tunable either by physical or chemical pressure, triggering the investigation of the pressure response of these systems. Here, we compare the lattice structure response of the two systems to the hydrostatic pressure. Under hydrostatic pressure, the lattice structure of LaAgSb$_2$ transformed from tetragonal to a mixed tetragonal (${\ge}$4 GPa) followed by monoclinic (4–9 GPa) and then to a mixed monoclinic and orthorhombic (9–41.8 GPa) phases. In contrast, our synchrotron X-ray diffraction results on LaAuSb$_2$ reveal that the tetragonal structure is stable in the pressure range of 0–12.2 GPa. Our experimental investigation is well supported by the density functional theory (DFT) calculations. We have used DFT to identify the experimental Raman vibrational modes at ambient conditions. We highlight the importance of structural subtleties in the differing pressure response of the ternary antimonides.

• Author Affiliations

1. Centre for High Pressure Research, School of Physics, Bharathidasan University, Tiruchirappalli 620024, India
2. Elettra-Sincrotrone Trieste S.C. p. A., S.S. 14, Km 163.5 in Area Science Park, 34149 Basovizza, Italy
3. Department of Physics, National Cheng Kung University, Tainan 70101, Taiwan
4. Taiwan Consortium of Emergent Crystalline Materials, Ministry of Science and Technology, Tapei 10601, Taiwan
5. Department of Chemistry, Centre for Materials Science and Nanotechnology, University of Oslo, Blindern, Oslo 0318, Norway

• Bulletin of Materials Science

Volume 46, 2023
All articles
Continuous Article Publishing mode

• Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020