Pressure induced electronic and structural transition in Ba2NiTeO6

This study explores the high-pressure evolution of Ba2NiTeO6 employing experimental and computational techniques. For the study of high pressure structural and vibrational properties, sychrotron XRD and micro-Raman spectroscopic experiments have been carried out. DFT calculates the structural and vibrational properties as a function of pressure to support the experimental findings. Also the electronic and magnetic properties as a function of pressure are investigated using DFT. Our study revealed a structural phase transition from a rhombohedral R-3m to a monoclinic C2/m phase at high pressure, with the emergence of new Bragg peaks and changes in lattice parameters, accompanied by a significant increase in bulk modulus. Some anomalies are observed in Raman mode frequencies along with the FWHM, indicate the presence of both electronic and structural transitions at different pressure values. These observations provide valuable insights into the pressure-driven behavior of Ba2NiTeO6 , emphasizing its complex interplay between structural, electronic, and vibrational properties. The signature of Raman modes as a function of pressure also showed an increasing nature of anharmonicity above 10 GPa, which is the possible precursur of the structural transition. These results highlight the importance of Ba2NiTeO6 in understanding the fundamental properties under pressure.