YUTAKA MIYAMOTO, ZDENEK ZELINGER, YOSHIHIRO NAKASHIMA AND KEIICHI TANAKA, Department of Chemistry, Faculty of Sciences, Kyushu University, Fukuoka, 812-8581 JAPAN.
The visible and near infrared emission spectrum in the 480 - 900 nm region of ICN+ was measured by Fourier transform spectrometer (Bruker IFS 120HR). The ICN+ was produced by Penning ionization of ICN with metastable He*. The ICN+ ion has much larger spin-orbit interaction constant (A=-4343 cm-1) than those of the ClCN+(-276 cm-1) and the BrCN+(-1477 cm-1)\footnoteJ. Fulara et al. , J. Phys. Chem. , 89, 4213-4219, (1985). The Renner-Teller effect appears in the
2 excited state of X2
. It is interesting to study the Renner-Teller effect of ICN+. Eight vibronic bands of the A2
+-X2
transition (both for the
=1/2 and 3/2 spin components) of ICN+ were observed. So far, the rotational analysis was performed for two vibronic bands, A2
+(000) -X2
3/2(000) and A2
+(000) - µ2
(010). Molecular constants, including the band origin, the effective rotational constant, centrifugal distortion constant and spin-rotation interaction constant, were determined for the A2
+ and X2
3/2 states.
Due to the Renner-Teller effect, the X2
(010) state was split into four vibronic components, µ2
,
2
, and 2
P(P=3/2 and P=5/2). For the A2
+ - µ2
band, P1, P2, R1 and R2-branch were observed. For the µ2
vibronic state,
-type doubling constant was determined as well as the rotational constant and centrifugal distortion constant. Renner parameter
for the X2
state was determined to be -0.197 from the
-type doubling constant. The determined Renner parameter (
=-0.197) was close to that of BrCN+(-0.185). We are now analyzing the spectrum for the
=1/2 spin component, A2
+(000) -X2
1/2(000) and A2
+(000) -
2
(010), to study the Renner-Teller effect in more detail.