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Title: Communication: Electronic transition of the l–C 6 + cation at 417 nm
A new electronic transition is reported for the linear C 6 + cation with an origin at 416.8 nm. This spectrum can be compared to the matrix isolation spectra at lower energies reported previously by Fulara et al. [J. Chem. Phys. 123, 044305 (2005)], which assigned linear and cyclic isomers, and to the gas phase spectrum reported previously by Campbell and Dunk [Rev. Sci. Instrum. 90, 103101 (2019)], which detected the same cyclic-isomer spectrum reported by Fulara. Comparisons to electronically excited states and vibrations predicted by various forms of theory allow assignment of the spectrum to a new electronic state of linear C 6 + . The spectrum consists of a strong origin band, two vibronic progression members at higher energy and four hot bands at lower energies. The hot bands provide the first gas phase information on ground state vibrational frequencies. The vibrational and electronic structure of C 6 + provide a severe challenge to computational chemistry.  more » « less
Award ID(s):
2154011
PAR ID:
10414953
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
12
ISSN:
0021-9606
Page Range / eLocation ID:
121102
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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