Vibrational and thermodynamic properties of high-pressure phases in LiYF4
A. Sen, S. L. Chaplot, R. Mittal
Abstract
Possible variations in the dynamical behaviour of LiYF4 due to its structural changes following several pressure-induced phase transitions are examined by making use of the complementary techniques of quasi-harmonic lattice dynamics and molecular dynamics simulation. The phonon spectra in the entire Brillouin zone and the respective Gibbs free energies are calculated for the three high-pressure polymorphs of LiYF4 that are stable at T = 0, with an aim to understand their relative stabilities as functions of pressure and temperature in terms of volume compression and vibrational entropy. Molecular dynamics simulations provide qualitative impressions about a temperature-driven second-order transformation and also of kinetic effects in the subsequent pressure-driven first-order phase transition. In addition, the calculations predict anomalous thermal expansion at low temperature in phases I and IIa while irreversibilty of phase II phase III transition on subsequent pressure release.
Create a lesson
Related papers
Access Rate-Dependent Endurance Behavior of Ferroelectric Hafnium Zirconium Oxide Capacitors
Roberto Guido, Julie Laguerre, Pramoda Vishnumurthy et al.
Identification of carbon-related color centers in hBN by high-resolution ab initio photoluminescence modeling
Vytautas Žalandauskas, Marek Maciaszek, Marianne Etzelmüller Bathen et al.
Sorption Molecular Dynamics of Point Defects in 2D Materials with a Machine Learning Potential
Nils-Ruben Skogemyr, Albin Sjöstedt, Isak Wernroth et al.
Transverse magneto-gyrotropy driven by spin-induced ferroaxiality
Yoshihiro Okamura, Takumi Kagawa, Ayano Nakamura et al.
A practical route to amorphous solid-state electrolyte structures by hybrid reverse Monte Carlo with foundation potentials
Xintian Wang, Xinyu Zhang, Denys Butenko et al.
Nonadiabatic polaron dynamics from machine-learned hopping trajectories
Daniela Mangano, Luca Leoni, Zhongfei Xu et al.