Jd. Howe et al., RESONANCE-ENHANCED MULTIPHOTON IONIZATION SPECTROSCOPY OF THE PF RADICAL, The Journal of chemical physics, 104(8), 1996, pp. 2789-2800
PF radicals in both their ground (X(3) Sigma(-)) and metastable (a 1 D
elta) electronic states have been produced by the gas phase reaction o
f F atoms with phosphine in a discharge flow reactor and detected by m
ass selective resonance enhanced multiphoton ionization (REMPI) spectr
oscopy in the wavelength range 410-225 nm. Analysis of the longer wave
length end of this spectrum (lambda>328 nm) has enabled identification
and spectroscopic characterization of five hitherto unknown Rydberg s
tates of this radical. These we label the h(1) Sigma(+) (T-0=57 324.9
cm(-1)), D (3) Delta (T-0=58 223.0 cm(-1)), E (3) Sigma(-)(T-0=58 690
cm(-1)), i 1 Delta (T-0=59 881.6 cm(-1)), and j (1) Sigma(-) (T-0=61 8
73.9 cm(-1)) states, respectively. [Origins, relative to the lowest ro
vibrational level of the ground (X (3) Sigma(-)) state are indicated b
y the numbers in brackets.] Quantum defect arguments suggest that all
five states derive from the electronic configuration [(2) Pi]4p pi(1).
Within the shorter wavelength region we identify two additional sets
of poorly resolved resonances which we associate with a further two Ry
dberg states belonging to series converging to the ground state ioniza
tion limit, followed by two extensive progressions of bands. Possible
assignments for these two progressions are considered. (C) 1996 Americ
an Institute of Physics.