The NO Dimer: Jet-Cooled Study of ν1and ν5Transitions

Uniform Supersonic Expansion for FTIR Absorption Spectroscopy: The ν5 Band of (NO)2 at 26 K

“…We selected the NO dimer as a test molecule and compared the performances of our FTIR/uniform expansion apparatus to those achieved using cryogenic (31,32) and free-jet coolings (33). The two Laval nozzles (number 1 and 2) tested to produce NO dimers are listed in Table 1.…”

The NO Dimer

“…This has been done for some jet-cooled spectrum of (NO) 2 recorded with a molecular jet coupled to a high-resolution spectrometer and appeared in a recent paper (17). This has been done for some jet-cooled spectrum of (NO) 2 recorded with a molecular jet coupled to a high-resolution spectrometer and appeared in a recent paper (17).…”

Infrared combination and difference bands of the NO dimer

“…In the mid-infrared region, there are two strong fundamental N-O stretching bands, m 1 at 1868.252 and m 5 at 1789.098 cm À1 . The former exhibits lines which are only slightly broadened (0.006 cm À1 ) by predissociation, and so it can be analyzed in detail [7][8][9][10][11]. The latter has greater predissociation broadening (0.13 cm À1 ), meaning that only an approximate profile analysis is possible [7,10,[12][13][14][15][16], as opposed to a line-by-line fit.…”

“…The former exhibits lines which are only slightly broadened (0.006 cm À1 ) by predissociation, and so it can be analyzed in detail [7][8][9][10][11]. The latter has greater predissociation broadening (0.13 cm À1 ), meaning that only an approximate profile analysis is possible [7,10,[12][13][14][15][16], as opposed to a line-by-line fit. The overtone region of the N-O stretch has also been characterized [12], most reliably for the 2m 5 and m 1 + m 5 bands which were observed under supersonic jet conditions in a study of NO dimer photodissociation dynamics [2].…”