The spectroscopic study of excited molecular cationCS2+ (Ã2πu ) by a different method is presented. In this technique the decay of excited states is monitored by measuring the photons emitted. The peaks in the photon spectrum would correspond to the energy levels of the ion. The vibrational-vibrational, vibrational-electronic interactions have been observed. Symmetry forbidden excitation of one quantum of bending vibration is observed which gives unperturbed value for the bending vibration. The Renner-Teller splitting for the δg and Σg- components of the bending mode (v2′ = 1) in the upper excited Ã2πu state has been observed. A tentative vibrational analysis of the Ã→ X system has been made.