Abstract
We report on an extensive study of ZnO materials with cagelike motifs in clusters and bulk phases through structural searches using the minima hopping method. A novel putative ground state was discovered for the cluster with a tubelike structure, closely related to the previously reported ground-state cage geometry. Furthermore, the effect of ionization on the geometries and energetic ordering of clusters with was studied by directly sampling the energy landscape of the ionized system. Our results indicate that the transition from ring and planar structures to three-dimensional cages occurs at larger cluster sizes than in the neutral system. Inspired by the bottom-up design philosophy and the predominance of cagelike structures in medium-sized clusters, a search for crystalline ZnO was conducted aimed specifically at low-density polymorphs, resulting in the discovery of 57 novel metastable phases. The voids in these low-density materials closely resemble the hollow cage structures of small clusters with . Analogous to clathrate materials, these voids could serve to accommodate guest atoms to tailor the materials properties for various applications.
5 More- Received 16 February 2017
- Revised 3 July 2017
DOI:https://doi.org/10.1103/PhysRevB.96.064108
©2017 American Physical Society