TY - JOUR
T1 - Photophysics of C2- (B2Σ u+) in rare gas lattices
T2 - Vibrational relaxation through intermediate a 4Σu+ levels
AU - Bondybey, V. E.
AU - Brus, L. E.
PY - 1975
Y1 - 1975
N2 - Time and wavelength resolved fluorescence techniques are used to investigate C2- (B2Σ) radiationless transitions following pulsed, tunable laser excitation. The purely radiative lifetimes in each host are Ne, ≃64 nsec; Ar, ≃40 nsec; Kr, ≃38 nsec; and Xe, ≃34 nsec. The principal B2Σ vibrational relaxation mechanism is a sequential process: crossing into a 4Σ, vibrational relaxation within 4Σ, and reverse crossing into B2Σ. The observed intermediate lifetimes strongly suggest that ν = 04Σ lies between ν = 0 and 1 of B2Σ; this fact allows assignment of gas phase B 2Σ ↔ a4Σ rotational perturbations reported by Herzberg and Lagerqvist. The unperturbed a4Σ constants are Te = 19448.4 cm-1, ωe = 1074.04 cm-1, Be = 1.1348 cm-1, ωexe = 24.68 cm-1, and αe = 0.0035 cm-1. Vibrational relaxation within a4Σ, and intersystem crossing, show a strong multiphonon relaxation energy gap law. The variation in behavior among the 12-12, 12-13, and 13-13 isotopes indicates that the photophysics is dominated by accidental near degeneracies with A2 II (and probably X2Σ) levels in addition to 4Σ levels.
AB - Time and wavelength resolved fluorescence techniques are used to investigate C2- (B2Σ) radiationless transitions following pulsed, tunable laser excitation. The purely radiative lifetimes in each host are Ne, ≃64 nsec; Ar, ≃40 nsec; Kr, ≃38 nsec; and Xe, ≃34 nsec. The principal B2Σ vibrational relaxation mechanism is a sequential process: crossing into a 4Σ, vibrational relaxation within 4Σ, and reverse crossing into B2Σ. The observed intermediate lifetimes strongly suggest that ν = 04Σ lies between ν = 0 and 1 of B2Σ; this fact allows assignment of gas phase B 2Σ ↔ a4Σ rotational perturbations reported by Herzberg and Lagerqvist. The unperturbed a4Σ constants are Te = 19448.4 cm-1, ωe = 1074.04 cm-1, Be = 1.1348 cm-1, ωexe = 24.68 cm-1, and αe = 0.0035 cm-1. Vibrational relaxation within a4Σ, and intersystem crossing, show a strong multiphonon relaxation energy gap law. The variation in behavior among the 12-12, 12-13, and 13-13 isotopes indicates that the photophysics is dominated by accidental near degeneracies with A2 II (and probably X2Σ) levels in addition to 4Σ levels.
UR - http://www.scopus.com/inward/record.url?scp=0346440542&partnerID=8YFLogxK
U2 - 10.1063/1.431605
DO - 10.1063/1.431605
M3 - Article
AN - SCOPUS:0346440542
SN - 0021-9606
VL - 63
SP - 2223
EP - 2231
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 5
ER -