A Study on the Compression Law of H- Ions in the Alkali Hydride Crystals by the Ionic Overlap-Compression Model

By using the ionic overlap-compression model, the parameter describing the state of H- by ions in the alkali hydride crystals (LiH, NaH and KH) was calculated by variation method. Then the numerical relations of and the relative radius of H- ions with the pressure were determined. The results show that the compression of H- ions has occurred before the pressure is added, and the compression law almost has nothing to do with the crystal structures. These two points are physically reasonable and were confirmed indirectly by the experiments.