Knowledge Bank

Lithium oxides of the form $Li2O$ and LiO have been produced for infrared study by the reaction of lithium atoms and nitrous oxide molecules at high dilution in nitrogen matrices. Analogous experiments using argon matrices produced no $Li2O$ or LiO species. Assignments made to LiO and the antisymmetric Li-O stretch of $Li2O$ are confirmed by isotopic substitutions of lithium and oxygen atoms, concentration studies, and comparison to earlier evaporative $Li2O$ work. Force constants calculated using the observed isotopic frequencies agree within 0.4% for four isotopic combinations of $Li2O$ and LiO. Normal coordinate calculations agree with earlier conclusions that $Li2O$ is a linear molecule.