A full description of the potential curve of the B 1Πu state of Li27

Abstract

An accurate potential curve for the bound and quasibound region of the B 1Πu state of Li27 is produced by analyzing high resolution sub-Doppler B 1Πu←X 1Σg+ excitation spectra in conjunction with lower resolution data of Hessel and Vidal [J. Chem. Phys. 70, 4439 (1979)] and of Russier et al. [J. Mol. Spectrosc. 168, 39 (1994)]. The bound and quasibound part of the curve is generated by the direct fit of molecular energies to a numerical potential; the outermost (repulsive) part of the curve is calculated by an asymptotic method using Coulombic and exchange parameters determined from the 1 1Πg and A 1Σu+ states of the lithium dimer. The full potential energy curve of the B 1Πu state reproduces all measured energies of f parity, and the widths of the predissociated lines, to within the experimental accuracy.