Atomistic modelization of the H-bonded ferroelectric KH2PO4 (poster)

J. LASAVE; R. L. MIGONI; J. KOHANOFF; S. KOVAL

Xi'an, China

Congreso; 12th International Meeting on Ferroelectricity; 2009

Xi'an Jiaotong University

A shell model (SM) for KH2PO4 (KDP), the prototype compound of the family of H-bonded ferroelectric materials, has been constructed by adjusting the interaction parameters to first-principles calculations. Structural properties, energy barriers, phonons, and the relative stability between the ferroelectric (FE) phase and a relevant antiferroelectric metastable structure associated to domain walls, compare very favorably to available first-principles and experimental data. Molecular dynamics simulations show that the model behaves satisfactorily within the FE phase. This model will be used to study the elusive structure of the paraelectric (PE) phase and the nature of the FE-PE phase transition.