Spectroscopy, Structure, and Ionization Energy of BeOBe

摘要

Electronic transitions of BeOBe have been investigated using laser-induced fluorescence and resonance enhanced multiphoton ionization techniques in the 27000-33000 cm-1 range. Vibronic progressions observed in these spectra were assigned to the symmetric and antisymmetric stretching vibrations in the excited electronic state. The nuclear spin statistics of the ground state, observed in the intensity patterns of rotationally resolved spectra, confirmed that the molecule is symmetric (BeOBe) and has 1Σg + symmetry. Analysis of the rotational structure yielded a value of 1.396(3) A for the BeO bond length. Ground state vibrational frequencies were determined using stimulated emission pumping. Photoionization efficiency curves were recorded that yielded a value of 8.119(5) eV for the BeOBe ionization energy. Multireference electronic structure calculations have been used to predict molecular constants and explore the orbital compositions of the ground and excited states.