Electronic Structure and Spectroscopy of CuBe.

Electronic spectra for CuBe were recorded using resonantly enhanced one-color, two-photon ionization techniques. Several vibronic progressions were observed, permitting characterization of the 4(2)Σ(+), 5(2)Σ(+), 3(2)Π and 4(2)Π excited states. Rotational resolution was achieved for a few bands, permitting determination of the ground state rotational constant. Attempts to record laser-induced fluorescence or two-color ionization spectra were unsuccessful. This was attributed to predissociation of the excited states. Density functional theory and ab initio electronic structure calculations were used to facilitate assignment of the observed states. Potential energy curves obtained from these calculations indicated that states arising from the Cu(3d(9)4s(2)) + Be(2s(2)) dissociation asymptote were well-positioned to cause predissociation of the observed states.