The distillation of binary mixtures of metals in vacuo . Part I.―Isolation of a compound of magnesium and zinc

A product of the formula AuCd has been isolated by Heycock and Neville by placing a known quantity of gold, together with a considerable excess of cadmium, in a hard glass tube exhausted by a mercury pump, and distilling the mixture for five or six hours at a temperature as high as the glass was capable of withstanding. The composition of the non-volatile residue always approximated closely to that required by the formula AuCd, and the authors concluded that the product was a definite inter-metallic compound. It would appear, however, from the work of Vogel, that these two metals are capable of forming the compounds Au 4 Cd 3 and AuCd 3 . The compound Au 4 Cd 3 forms a series of solid solutions with cadmium, and this author concludes that the product AuCd isolated by Heycock and Neville "dürfte daher als ein kadmium-reicherer Mischkristall der Verbindung Au 4 Cd 3 aus der Reihe Be, seine Zusammensetzung als eine zufällige zu betrachten sein. At the suggestion of Mr. Heycock, the author has commenced a general investigation of the distillation of binary mixtures of metals, one of which at least is readily volatile, in order to ascertain if this method is of general applicability as a means of isolating inter-metallic compounds.