In this paper, we present a thorough investigation of vibrational, structural, and electronic properties of perovskite-type rhombohedral Ba2ZnTeO6 (BZTO) under systematic application of pressure. To carry out the analysis, we have performed pressure-dependent Raman spectroscopic measurements, synchrotron XRD, and density functional theory-based calculations. At ambient conditions, BZTO stabilizes in R3ˉm space group, which under pressure undergoes a structural transition to a monoclinic phase with space group C2/m at around 18~GPa. In-depth Raman analysis reveals softening of a phonon mode Eg (∼ 28cm−1) leads to the structural phase transition. First principle DFT calculations also indicate that the doubly degenerate soft mode associated with the in-phase TeO6 octahedral rotation drives the structure to a lower symmetry phase C2/m.
@article{arxiv.2503.11971,
title = {Soft mode induced structural phase transition in Ba$_2$ZnTeO$_6$ at high pressure},
author = {Bidisha Mukherjee and Surajit Adhikari and Mrinmay Sahu and Asish Kumar Mishra and Bhagyashri Giri and Priya Johari and Konstantin Glazyrin and Goutam Dev Mukherjee},
journal= {arXiv preprint arXiv:2503.11971},
year = {2025}
}