Knowledge Bank

Photodissociation infrared spectra of mass selected LiD$\mathrm{2+}$ and LiH$\mathrm{2+}$ have been obtained in the D-D and H-H stretch region respectively, using a tandem mass spectrometer and detecting the Li$+$ loss channel. For the first time rotationally resolved spectra of these complexes are available providing structural parameters and allowing direct comparison with theoretical data } \textbf{96}, 2004, 205-216}. For LiD$\mathrm{2+}$ around 100 lines of the K=0$\leftarrow$K=0, K=1$\leftarrow$K=1, and K=2$\leftarrow$K=2 parallel transitions were fitted to a Watson A-reduced Hamiltonian. The analysis of the spectrum was supported by quantum chemical calculations using the program TRIATOM } \textbf{75}, 1993, 339-364.} and the potential from Gianturco \textit{et al.} } \textbf{119}, 2003, 11241-11248}. The LiD$\mathrm{2+}$ complex was found to have T-shaped structure in agreement with theoretical predictions. An analogous analysis has been performed for the LiH$\mathrm{2+}$ spectrum which differs from the LiD$\mathrm{2+}$ spectrum due to larger rotational constants and an altered ortho:para ratio.