Metavalent bonding in crystalline solids: how does it collapse?
Abstract
The chemical bond is one of the most powerful, yet controversial concepts in chemistry, explaining property trends in solids. Recently, a novel type of chemical bonding has been identified in several higher chalcogenides, characterized by a unique property portfolio, unconventional bond breaking and sharing of about one electron between adjacent atoms. Metavalent bonding is a fundamental type of bonding besides covalent, ionic and metallic bonding, raising the pertinent question, if there is a well-defined transition between metavalent and covalent bonding. For three different pseudo-binary lines, namely GeTe1-xSex, Sb2Te3(1-x)Se3x and Bi2-2xSb2xSe3, a sudden drop in several properties, including the optical dielectric constant, the Born effective charge, the electrical conductivity as well as the bond breaking is observed once a critical Se or Sb concentration is reached. This finding provides a blueprint to explore the impact of metavalent bonding on attractive properties utilized in phase change materials and thermoelectrics.
Cite
@article{arxiv.2008.10219,
title = {Metavalent bonding in crystalline solids: how does it collapse?},
author = {L. Guarneri and S. Jakobs and A. von Hoegen and S. Maier and O. Cojocaru-Mirédin and M. Raghuwanshi and M. Drögeler and C. Stampfer and R. P. S. M. Lobo and A. Piarristeguy and A. Pradel and M. Xu and M. Wuttig},
journal= {arXiv preprint arXiv:2008.10219},
year = {2020}
}