Two-photon spectroscopy of the low lying Rydberg states of NO. II. Application to the NO–Ar complex

Abstract

Two-photon spectroscopy of the low lying Rydberg states of NO. I. The 3p and 3d complexes

Interaction of the NO 3pπ (C 2Π) Rydberg state with RG (RG = Ne, Kr, and Xe): Potential energy surfaces and spectroscopy

“…Knowing the source of each spectral component allows insight into the assignment of the spectrum, and indicates that significant stretch/bend mixing occurs, even early on in the spectrum, while slightly higher in energy various Fermi resonance interactions are likely occurring, causing further mixing. The overall appearance of the NO-Ar and NO-Kr simulated spectra is similar to that achieved in earlier work by Mack et al 21 which were obtained employing the model of Meyer, 22 where the two-photon intensity was included explicitly. As noted previously, 1 we take this to imply that the explicit inclusion of the two-photon intensities is not required for this level of agreement.…”

“…We investigated this and it seemed that some of the experimental features to the red of the main bands could be attributable to hot features; however, it was not possible to be conclusive on this as the match in intensities was not overwhelmingly convincing. The experimental REMPI spectrum was mass-resolved and is of the NO-20 Ne isotopologue-it was found that the spectrum of the isotopologue NO- 22 Ne was identical within the experimental resolution. 20 We also note that in Ref.…”

“…20 and that of NO-Ar from Ref. 22. For the D 0 value for thẽ X state, we take a value of 94 cm −1 , which is between the two most recent determinations of 93.8 ± 0.9 cm −1 (Ref.…”

“…With the a axis being almost coincident with the intermolecular axis, we see that rotation about this axis is close to being solely NO rotation, and so we expect to be able to see the structure associated with this in the spectrum; this was considered in detail by Meyer. 22 We can represent this motion by a quantum number K a . On the other hand, the (almost equivalent) rotation of the whole complex about either of the b and c axes each has a very large moment of inertia, owing to the movement of the RG atom about the centre of mass.…”

“…21 Meyer and coworkers have suggested an interpretation of theC state spectra 20,21 in terms of progressions of intermolecular stretches and bends, but with associated structure attributable to rotation of the complex about the a inertial axis (almost coincident with the Jacobi R direction) being a key aspect of the spectrum. This interpretation built on the model put forward by Meyer to explain the NO-Ar spectrum 22 -see also Ref. 1.…”