L. Krim et N. Lacome, THE NO DIMER, N-14 AND N-15 ISOTOPOMERS ISOLATED IN ARGON MATRIX - A NEAR-INFRARED, MID-INFRARED, AND FAR-INFRARED STUDY, The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory, 102(13), 1998, pp. 2289-2296
A near- and far-infrared study of (NO)-N-14-(NO)-N-14 and its isotopom
ers, (NO)-N-14-(NO)-N-15 and (NO)-N-15-(NO)-N-15, isolated in argon ma
trix has been carried out. Infrared active fundamental vibrational mod
es, nu(1), nu(2), nu(3), nu(5), and nu(6), for each species of the dim
er have been observed, as well as overtone bands 2 nu(1), 2 nu(5) and
combination bands nu(1) + nu(5), nu(1) + nu(6), nu(5) + nu(6), and nu(
4) + nu(5). Frequency of the nonactive v4 mode was also retrieved from
combination bands. From the knowledge of the 18 available frequencies
of the three isotopic species, force constants for the cis-ON-NO have
been calculated. The force constants characterizing the N-N stretchin
g mode and the ONN bending mode are found to be 0.39 mdyn/Angstrom and
0.42 mdyn Angstrom/rad(2), respectively. The potential energy distrib
ution calculated for each vibration showed that the nu(2) and nu(3) mo
des are strongly coupled and that there is no pure N-N stretching mode
. In the same way, the nu(1) mode could be considered as a pure NO str
etching mode while the vs one is coupled to the ONN bending.