Muonium hydride: The lowest density crystal

A muonium hydride molecule is a bound state of muonium and hydrogen atoms. It has half the mass of a parahydrogen molecule and very similar electronic properties in its ground state. The phase diagram of an assembly of such particles is investigated by first-principles quantum simulations. In the bu...

Full description

Bibliographic Details
Main Authors: Youssef Kora, Massimo Boninsegni, Dam Thanh Son, Shiwei Zhang
Format: Article
Language:English
Published: American Physical Society 2021-05-01
Series:Physical Review Research
Online Access:http://doi.org/10.1103/PhysRevResearch.3.023113
Description
Summary:A muonium hydride molecule is a bound state of muonium and hydrogen atoms. It has half the mass of a parahydrogen molecule and very similar electronic properties in its ground state. The phase diagram of an assembly of such particles is investigated by first-principles quantum simulations. In the bulk limit, the low-temperature equilibrium phase is a crystal of extraordinarily low density, lower than that of any other known atomic or molecular crystal. Despite the low density and particle mass, the melting temperature is surprisingly high (close to 9 K). No (metastable) supersolid phase is observed. We investigated the physical properties of nanoscale clusters (up to 200 particles) of muonium hydride and found the superfluid response to be greatly enhanced compared to that of parahydrogen clusters. The possible experimental realization of these systems is discussed.
ISSN:2643-1564