New experimental and theoretical assessment of the dissociation energy of C₂

ABSTRACT

The dissociation energy in the ${\mathrm{X}}^1{\mathrm{\Sigma }}_{\mathrm{g}}^{+}$ electronic ground state of the carbon dimer ${\mathrm{C}}_2$ is determined spectroscopically from a combined treatment involving resonant four-wave mixing experiments and highly accurate multi-reference configuration interaction calculations to be $(50370\pm 150)hc\mathrm{cm}{}^{-1}$ ($(6.24\pm 0.02)$ eV, $(602\pm 2)$ kJ mol⁻¹). This new value allows us to clarify current discrepancies among other experimental and theoretical results, which will be discussed.

GRAPHICAL ABSTRACT

Keywords:

• Double-resonant four-wave mixing spectroscopy
• explicitly correlated multi-reference configuration interaction
• combustion
• dissociation energy

Acknowledgments

We thank CNRS and Université de Strasbourg.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Bradley Visser http://orcid.org/0000-0002-9798-3079

Martin Beck http://orcid.org/0000-0002-4475-3587

Peter Bornhauser http://orcid.org/0000-0003-1293-2668

Gregor Knopp http://orcid.org/0000-0002-0786-3402

Jeroen Anton van Bokhoven http://orcid.org/0000-0002-4166-2284

Peter Radi http://orcid.org/0000-0003-1197-1091

Christophe Gourlaouen http://orcid.org/0000-0002-2409-2849

Additional information

Funding

This work has been supported by the European Cooperation in Science and Technology (COST) action CM1405 (MOLIM) and is also supported by the Swiss National Science Foundation (Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung) (Grant No. 200020_175490/1).