an alkali metal to produce a liquid material of the form m 3 ga in another embodiment of this invention the new liquid alloy li 3 ga can be used as a hsm this can be hydrogenated to form the solid compound li 3 gah 6 which has a hydrogen content of 6 3 wt hydrogen very close to criterion 1 stated above another suitable hsm according to the invention is na 3 gah 6 which will release h 2 around 100 u00b0 c the liquid nature of the depleted li 3 ga renders it mobile and significantly enhances its rehydrogenation to li 3 gah 6 and the process circumvents the poor kinetic uptake of h 2 associated with many hsms which are solid in the discharged state q v in other embodiments of the invention the liquid alloy may be na 3 ga corresponding to na 3 gah 6 with 4 1 wt hydrogen or a mixed ternary alloy such as namgga corresponding to namggah 6 with 4 9 wt hydrogen for these hsms the lower hydrogen content may be compensated by superior hydrogenation and dehydrogenation characteristics materials of the type m 3 gah 6 may be prepared using the following two methods the first of these involves direct synthesis under a hydrogen atmosphere as.