Spectroscopic characterization of the Zn(4s2)·Ne[1Σ+] and Zn(4s4pπ)·Ne[1Π1] van der Waals states

The Zn(4s2)·Ne[1Σ+] and the Zn(4s4pπ)·Ne[1Π1] states have been characterized by laser-induced fluorescence spectroscopy. Bond lengths were determined from simulations of the partially-resolved rotational structure of the 1Π ← 1Σ+ transitions, while bond strengths were estimated from a Birge–Sponer extrapolation with allowance for consistent errors resulting from similar procedures in the analogous Cd·Ne and Hg·Ne transitions. The van der Waals bonding in these states is discussed briefly and compared to that in the analogous M·RG states, where M=Mg, Zn, Cd, Hg and RG=Ne, Ar, Kr, Xe.