ELECTRONIC-STRUCTURE OF NE-2 BELOW THE 1ST IONIZATION LIMIT

Results from new laser excitation spectra of Ne-20(2) have been combined with previously published experimental and theoretical data to provide a consistent picture describing many of the Rydberg states observed below the first ionization limit. These states are found to fall mainly into Rydberg series converging on the ...3-sigma(u) X (2)SIGMA(u)+ ground core of Ne2+. Spectral data for the np-sigma (3)SIGMA(g)+ <-- a (3)SIGMA(u)+ and np-pi (3)PI(g) <-- a (3)SIGMA(u)+ series support the current assignments of the upper states. Although (0-0) bands dominate these series, other vibronic transitions are observed. The 6-23p-sigma (3)SIGMA(g)+-a(0-0) bands are more perturbed than the np-pi (3)PI(g)-a(0-0) series; hence, data for 4-17p-pi (3)PI(g)+-a(0-0) and 4-6f-lambda((3)SIGMA(g)+,(3)PI(g)+)-a(0-0) were used to determine a value of 34 409 +/- 2 cm-1 for the lowest ionization limit of Ne-20(2). Rotational constants for the upsilon = 0 levels of 4-17p-pi (3)PI(g) and 10-23p-sigma (3)SIGMA(g)+ also are presented.