Matrix Isolation Spectroscopy of Bismuth Atoms and Molecules
Tomonari Wakabayashi, Asuka Endo, Miho Hatanaka, Yusuke Morisawa
Department of Chemistry, Kindai University, Higashi-Osaka 577-8502, Japan,
[email protected]
Bismuth atoms and molecules have unique properties stemming from the atomic configuration of
6p3 for showing large spin-orbit coupling in such a heavy element [1,2]. The mixing of different
spin states results in relatively slow emission of photons from low-lying excited electronic states.
We have investigated matrix-isolated bismuth atoms and molecules in solid neon matrices by
laser-induced fluorescence (LIF) spectroscopy with selective excitation of Bi, Bi2, and Bi3 [3-5].
Recent studies of the Bi/Ne system lead us to identify four low-lying excited states in the trimer,
Bi3, through the observation of a series of new near-infrared (NIR) photoemission band systems
in transition energies of 6600-13500 cm-1, exhibiting vibrational progression of 150 cm-1 [4,5].
Bismuth dimer, Bi2, has extensively studied in
its vapor phase, as is known for its strong
emission lines in the A-X system with the origin
band at 17720 cm-1 [1]. We observed dispersed
fluorescence spectra (DF) for the A-X transition
in Bi2 in solid Ne to obtain the ground-state
vibrational frequency of 174 cm-1, reconfirming
the result in the literature by Raman
spectroscopy [2].
Photoexcitation of Bi atoms in solid Ne is
followed by slow emission of photons from the
low-lying electronic states stemming from the
same 6p3 configuration as that for the 4S3/2
ground state [3]. Figure 1 shows a typical time
profile of the photoemission for the 2D5/2-4S3/2
transition following the 2P1/2-4S3/2 excitation.
Rise and decay are apparent in the population at
the upper 2D5/2 level.
[1] G. Gerber et. al., J. Chem. Phys. 64, 3410 (1976)
[2] V. E. Bondybey et al., Chem. Phys. Lett. 76, 30 (1980)
[3] A. Fukumi et al., Prog. Theor. Exp. Phys., 04D002 (2012)
[4] T. Wakabayashi et al., Eur. Phys. J. D 67, 36 (2013)
[5] T. Wakabayashi et al., J. Phys. Chem. A 119, 2644 (2015)
Fig. 1. Time profile of the 2D5/2-4S3/2 emission
following the 2P1/2-4S3/2 excitation of Bi atoms in
solid Ne. Rise and decay are apparent for the cascade
of relaxation processes. Inset shows the level scheme
for all the possible states from 6p3 configuration of
atomic Bi in the gas phase.