| Abstract Scope |
Understanding the impact of atomic structure on thermal properties like thermal conductivity is crucial to the design of emerging materials used in energy applications. These key properties are governed by phonon anharmonicity, the non-linearity of interatomic forces. In this talk, a framework is presented for understanding phonon anharmonicity in relation to atomic structure. For example, using a model system, we investigate phonon anharmonicity as it relates to the shift in phonon eigenvectors between structures. A mode-matching algorithm allows for direct comparison of mode anharmonicities, showing that materials with similar mode shapes have similar mode anharmonicities regardless of differences in mode frequency. This suggests that eigenvector alignment relative to structural motifs plays a central role in determining the distribution and magnitude of phonon anharmonicity. Thus, a crystal chemistry perspective of lattice dynamics is likely to inform new strategies for tuning anharmonic properties of solids for the development of thermal materials. |