Laser-induced fluorescence of matrix-isolated HCCCCCN+ and HCCCCCCCN+

✍ Scribed by Alice M. Smith; Jürgen Agreiter; Vladimir E. Bondybey

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 599 KB
• Volume: 244
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00915-q

✦ Synopsis

The cyanodiacetylene (HCsN +) and cyanotriacetylene (HCTN +) cations were produced in a pulsed supersonic discharge through a dilute cyanoacetylene (HC3N) neon mixture, and isolated in solid neon at 5-7 K. The A 2 H-X 2II transitions of these cations were investigated by means of laser excitation and Fourier-transform emission spectroscopy. New ground-state vibrational information is obtained for HCsN + and HC7 N+. The latter is identified with the help of a particle-in-a-box model of electronic transition energies of these long-chain linear ions. Its identity is confirmed by analysis of the observed vibronic structure. Interesting matrix site effects lead to the observation of the AI2 = + 1 transitions for one of the two sites. These yield the spin-orbit splitting constants Aoo = 92 cm-l and A o = 17 cm-i for HCsN + and At~ = 91 cm-~ and A 0= 19cm -I forHC7 N+.