Emission spectra of 1,2,3-butatriene cation H2CCCCH2+ by hollow-cathode glow discharge and extended negative glow discharge

- The 1,2,3-butatriene cation H2CCCCH2+ was observed in optical emission.
- H2CCCCH2+ was effectively produced by the discharge of 2-butyne (H3CCCCH3).
- The observed bands of H2CCCCH2+ were assigned to the 2B3u-X2B2g electronic transition.
- The frequency of the v = 0-0 origin band of the 2B3u-X2B2g electronic transition was evaluated to be 20 381 cm−1.