Spectroscopic characterization of the hydrogen bonded OC–HI in supersonic jets

Publisher Website
Google Scholar
Abstract
The hydrogen bond OC–HI has been characterized using high resolution microwave and infrared spectroscopies in supersonic seeded molecular jets. Ground state molecular parameters of the 16O12C–HI and 16O13C–HI isotopic species determined by the pulsed‐nozzle Fourier transform microwave supersonic jet technique include: for 16O12C–HI, B 0 (MHz)=900.9522(1), D J (kHz)=2.519(1), C N (kHz)=0.94(18), χ(MHz)=−1346.238(13), χ J (kHz)=−8.27(31). The corresponding values for 16O13C–HI are 882.5997(2), 2.404(2), 0.87(19), −1349.481(17), and −7.76(28). This analysis is consistent only with a linear equilibrium dimer structure in which the proton is bound to the carbon atom of carbon monoxide. Other derived dimer parameters include: r(C–I)=4.271(2) Å, αav=24.8°, k σ(N m−1)=1.713. Infrared diode laser investigations provide a band origin frequency ν0 of 2148.549 040(29) cm−1 for the ν2 C≡O stretching fundamental vibration. This corresponds to a blue shift of 5.277 28(37) cm−1 relative to free monomer CO. Excited state molecular constants B 2=898.2728(33) MHz. and D J (2)=2.614(24) kHz are also determined. Line profiles are consistent with an excited state lifetime ≥0.54 ns.