Rovibration spectrum study of three hot bands with ν′′ ⩾ 18 in the second negative system ( [formula omitted]– [formula omitted]) of 16O 2+ ion

Abstract

The second negative ( A 2 Π u – X 2 Π g ) system of O 2 + was studied in the near infrared region at high resolution using a Ti–sapphire laser system. Optical heterodyne magnetic rotation enhanced velocity modulation technique was employed to record rich absorption spectrum, three new hot bands (3, 18), (4, 19), and (3, 19) were observed and rotationally analyzed for the first time by a nonlinear least-square fitting procedure using a standard Hamiltonian, thus, precise molecular constants of the states involved were obtained.