THE (3S, 3D) 1-DELTA-G ELECTRONIC STATE OF NA2

Ultraviolet lines of both krypton-ion and argon-ion lasers excite levels in the C(2)1-PI-u state of Na2. Following efficient collisional transfer to (1)1-DELTA-g, the (0-0) sequence of the (1)1-DELTA-g-B(1)1-PI-u system appears strongly in the infrared around 7020 cm-1. High-resolution Fourier transform spectra have been analysed to derive constants of the 1-DELTA-g state, for which T(e) = 27338.46 cm-1. Its properties, with omega-e = 130.0 cm-1, B(e) = 0.1255 cm-1, D(e) 7857 cm-1, and a quantum defect of almost zero, are some way from those of a pure Rydberg state.