Absorption in the near-ultraviolet wing of the Kr2F*(410 nm) band

An intracavity laser technique has been used to study the absorption of electron-beam pumped Ne/Kr/F
2
gas mixtures (196 and 300 K) in the "blue wing" of the Kr
2
F emission continuum. The experiments were conducted at 358 nm using the
\upsilon' = 0 \rightarrow \upsilon" = 1
transition of the N
2
(
C \rightarrow B
) laser. Comparing the results with the predictions of a computer model, the species primarily responsible for absorption have been identified as Ne+
2
, Kr+
2
, and Kr
2
F*. The photoabsorption cross sections for Ne+
2
and Kr
2
F (Kr+
2
F-) at 358 nm have been estimated to be
8.1 \cdot 10^{-19}
and
5.4 \cdot 10^{-18}
cm
²
, respectively. The Kr
2
F* absorption cross section is roughly 20 percent of that reported for Kr+
2
at the same wavelength. The fluorescence efficiency of Kr
2
F* in
e
-beam excited 94.93 percent Ne/5 percent Kr/0.07 percent F
2
(
P_{total} = 4000
torr) gas mixtures has been found to be a factor of 2.8 higher than that of the N
2
(
C \rightarrow B
) band in Ar/5 percent N
2
mixtures. Also, the rate constant for quenching of Kr
2
F* by F
2
was measured to be
(4.1 \pm 0.5) \cdot 10^{-10}
cm
³
. s
^-1
at 300 K and
(3.0 \pm 0.5) \cdot 10^{-10}
cm
²
. s
^-1
at 196 K.