The band spectra of scandium-, yttrium-, and lanthanum monoxides

The ordinary arc spectra of scandium, yttrium, and lanthanum show, in addi- tion to lines characteristic of neutral and ionized atoms, complex banded struc- tures which are ascribed to a molecular compound of the atoms with <\\ These bands have the same general appearance as those due to well-known diatomic molecules and are, therefore, attributed to ScO, YO, and LaO, rather than to the chemically stable oxides Sc2 3 , Y 2 3 , and La 2 3 .