Modeling non-harmonic behavior of materials from experimental inelastic neutron scattering and thermal expansion measurements.

Loading...
Thumbnail Image

Date

2016-09-28

Journal Title

Journal ISSN

Volume Title

Repository Usage Stats

176
views
152
downloads

Citation Stats

Attention Stats

Abstract

Based on thermodynamic principles, we derive expressions quantifying the non-harmonic vibrational behavior of materials, which are rigorous yet easily evaluated from experimentally available data for the thermal expansion coefficient and the phonon density of states. These experimentally-derived quantities are valuable to benchmark first-principles theoretical predictions of harmonic and non-harmonic thermal behaviors using perturbation theory, ab initio molecular-dynamics, or Monte-Carlo simulations. We illustrate this analysis by computing the harmonic, dilational, and anharmonic contributions to the entropy, internal energy, and free energy of elemental aluminum and the ordered compound [Formula: see text] over a wide range of temperature. Results agree well with previous data in the literature and provide an efficient approach to estimate anharmonic effects in materials.

Department

Description

Provenance

Subjects

Citation

Published Version (Please cite this version)

10.1088/0953-8984/28/38/385201

Publication Info

Bansal, Dipanshu, Amjad Aref, Gary Dargush and Olivier Delaire (2016). Modeling non-harmonic behavior of materials from experimental inelastic neutron scattering and thermal expansion measurements. J Phys Condens Matter, 28(38). p. 385201. 10.1088/0953-8984/28/38/385201 Retrieved from https://hdl.handle.net/10161/11987.

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.

Scholars@Duke

Delaire

Olivier Delaire

Associate Professor of the Thomas Lord Department of Mechanical Engineering and Materials Science

The Delaire group investigates atomistic transport processes of energy and charge, and thermodynamics in energy materials. We use a combined experimental and computational approach to understand and control microscopic energy transport for the design of next-generation materials, in particular for sustainable energy applications. Current materials of interest include superionic conductors, photovoltaics, thermoelectrics, ferroelectrics/multiferroics, and metal-insulator transitions. Our group's studies provide fundamental insights into  atomic dynamics and elementary excitations in condensed-matter systems (phonons, electrons, spins), their couplings and their effects on macroscopic properties. We probe the microscopic underpinnings of transport and thermodynamics properties by integrating neutron and x-ray scattering, optical spectroscopy, and thermal characterization, together with quantum-mechanical computer simulations.


Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.