The Far-Infrared Spectrum of HI

✍ Scribed by K.V. Chance; T.D. Varberg; K. Park; L.R. Zink

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 367 KB
• Volume: 162
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1993.1272

✦ Synopsis

We have measured the rotational spectrum of (\mathrm{H}^{127} \mathrm{I}) from 0.38 to (4.58 \mathrm{THz}\left(13-153 \mathrm{~cm}^{-1}\right)), encompassing the (R(0)) through (R(11)) rotational lines. using the (\mathrm{CO}_{2}) laser difference method for generating coherent far-infrared radiation at the National Institute of Standards and Technology. A total of 49 features were measured and fitted to obtain parameters for a molecular Hamiltonian which includes terms up to octic in rotational angular momentum, the iodine quadrupole coupling constant and its rotational dependence, and the iodine nuclear spin-rotation interaction. The measured features include mostly fully resolved lines, which permit an accurate determination of the hyperfine structure. There are also three groupings of lines where independent fits to the hyperfine components are not possible; these latter groupings are fitted with fixed quadrupole and spin-rotation splittings determined from the fully resolved lines. to obtain further information on the rotational constants. The rotational dependence of eqQ( (\left.{ }^{127} I\right)) measured here is combined with previous measurements of its vibrational dependence to determine the electric field gradient at the ({ }^{127} I) nucleus and its first two derivatives with respect to the internuclear distance. : 1993 Academic Press. Inc.