Lithium Dihydrogen Fluoride—An Approach to Metallic Hydrogen

The possibility of making a new form of hydrogen in the metallic state through preparation of the compound Li${\mathrm{H}}_2$F is discussed. A proposed structure is specified which is believed to be nearly stable under ambient conditions. The pressures needed to stabilize this compound and to convert it to a metal are estimated. It may have an exceptionally high hydrogen density, high electrical conductivity, high Debye temperatures in the hydrogen sublattice, and perhaps a high superconducting transition temperature.