UV absorption spectrum of allene radical cations in solid argon

Chih-Hao Chin; Meng-Yeh Lin; Tzu-Ping Huang; Yu-Jong Wu

doi:10.1016/j.saa.2018.02.028

UV absorption spectrum of allene radical cations in solid argon

Spectrochim Acta A Mol Biomol Spectrosc. 2018 May 5:196:233-237. doi: 10.1016/j.saa.2018.02.028. Epub 2018 Feb 8.

Authors

Chih-Hao Chin¹, Meng-Yeh Lin¹, Tzu-Ping Huang¹, Yu-Jong Wu²

Affiliations

¹ National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan.
² National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan; Department of Applied Chemistry, National Chiao Tung University, 1001, Ta-Hsueh Road, Hsinchu 30010, Taiwan. Electronic address: yjwu@nsrrc.org.tw.

PMID: 29454251
DOI: 10.1016/j.saa.2018.02.028

Abstract

Electron bombardment during deposition of an Ar matrix containing a small proportion of allene generated allene cations. Further irradiation of the matrix sample at 385 nm destroyed the allene cations and formed propyne cations in solid Ar. Both cations were identified according to previously reported IR absorption bands. Using a similar technique, we recorded the ultraviolet absorption spectrum of allene cations in solid Ar. The vibrationally resolved progression recorded in the range of 266-237 nm with intervals of about 800 cm^-1 was assigned to the A²E ← X²E transition of allene cations, and the broad continuum absorption recorded in the region of 229-214 nm was assigned to their B²A₁ ← X²E transition. These assignments were made based on the observed photolytic behavior of the progressions and the vertical excitation energies and oscillator strengths calculated using time-dependent density functional theory.

Keywords: C(3)H(4)(+); Electronic transition; Matrix isolation; UV absorption spectrum.