3576. ---------------. [VON STACKELBERG, M.] [Crystal Structures of Several Carbides and Borides.] Ztschr. Elektrochem., vol. 37, 1931, pp. 542-545; Chem. Abs., vol. 25, 1931, p. 5812.
In order to form a carbide of the CaC2 type, hydrolyzing to C2H2 with H2O, a minimum metal-ion size is necessary. The metallic properties of most carbides of this formula are due to the presence of 2 extra valence electrons. Ca, Sr, Ba, La, Ce, and Th form borides of formula MeB6 with CsCl-type cubic lattice.