High-resolution infrared spectroscopy of diacetylene below 1000 cm-1

Luca Bizzocchi (1) , Filippo Tamassia (2) , Claudio Degli Esposti (3) , Luciano Fusina (2) , Elisabetta Canè (2) , Luca Dore (3)

1 CAAUL - Centro de Astronomia e Astrofísica da Universidade de Lisboa
2 Dipartimento di Chimica Fisica e Inorganica [Bologna]
3 Dipartimento di Chimica "G. Ciamician"

The infrared spectrum of diacetylene has been recorded at high resolution between 500 and 1000 cm-1 by Fourier transform spectroscopy. More than 1200 transitions were assigned to 5 bands: the nu8 fundamental, the nu7+nu9 combination, and the nu3−nu9 difference bands as well as the most intense nu8+nu9−nu9 and nu7+2nu9−nu9 hot bands. The data were analysed together with the previously recorded millimetre-wave lines for the nu8−nu6 and nu8+nu9−(nu6+nu9) difference bands. Rotational and vibrational l-type resonances, together with the cubic anharmonic interactions which couple the v3 = 1 stretching state with the v8 = v9 = 1 combination and v7 = 2 overtone states have been considered in the least-squares fits to the observed wavenumbers in order to derive reliable spectroscopic parameters. The spectral analyses deliver very precise B0 and D0 parameters and experimental values of the anharmonicity constants for the bending-bending combination states of diacetylene below 1000 cm-1.

Mots clés: Physical Sciences

Domaines: Matière Condensée [cond-mat]

Luca Bizzocchi, Filippo Tamassia, Claudio Degli Esposti, Luciano Fusina, Elisabetta Canè, et al.. High-resolution infrared spectroscopy of diacetylene below 1000 cm-1. Molecular Physics, 2011, pp.1. ⟨10.1080/00268976.2011.604646⟩. ⟨hal-00723631⟩