Ferroelectric Phase Transitions from First Principles

Abstract

An effective Hamiltonian for the ferroelectric transition in $PbTi{O}_3$ is constructed from first-principles density-functional-theory total-energy and linear-response calculations through the use of a localized, symmetrized basis set of ``lattice Wannier functions.'' Preliminary results of Monte Carlo simulations for this system show a first-order cubic-tetragonal transition at 660 K. The involvement of the Pb atom in the lattice instability and the coupling of local distortions to strain are found to be particularly important in producing the behavior characteristic of the $PbTi{O}_3$ transition. A tentative explanation for the presence of local distortions experimentally observed above $T_c$ is suggested. Further applications of this method to a variety of systems and structures are proposed for first-principles study of finite-temperature structural properties in individual materials.

14 pages, harvmac, 4 uuencoded figures

References in corpus (5)

• Multicanonical Ensemble: A New Approach to Simulate First-order Phase Transitions
• Phase transitions in BaTiO${}_3$ from first principles
• Phonon Properties of Knbo3 and Ktao3 from First-Principles Calculations
• Path Integral Monte Carlo Study of a Model 2D Quantum Paraelectric
• Gamma phonons and microscopic structure of orthorhombic KNbO3 from first-principles calculations

Cited by in corpus (1)

• Ab Initio Study of the Structural Phase Transition in Cubic Pb_3GeTe_4