“…A second and even more general synthesis of hydrides is a modification of the direct synthesis where the hydrogen is activated by a glow discharge. The reaction of atomic hydrogen with metals and compounds of metals has been studied extensively, and with the possible exception of cadmium, chromium, iron, mercury, palladium, tungsten, and zinc, hydrides of practically all the hydride-forming elements have been so prepared (26,27,28,29,30). The hydrides formed in some cases, although giving correct analyses, appear to be different from those prepared by other means; this is possibly due to polymerization or possibly due to the absence of metallic impurities.…”