Excited rotational states

The dependence of Av, the frequency spread, on results in a much larger value for an excited electronic state, typically 30 MHz, than for an excited rotational state, typically 10 Hz, because of the much greater v for an excited electronic state. 

M. Quack The situation Prof. Woste refers to corresponds to excited rotational states of highly excited ion pair (electronic) states, which are well known for diatomic molecules, for example. 

Fig. 12.5. Zeroth-order potentials Veff(R-,j,Sl,J) defined in (12.7) for fl = 0 and several total angular momentum quantum numbers J. The excited rotational states can decay either by tunneling (shape resonances) or by rotational predissociation ( Feshbach resonances) as indicated by the horizontal arrows. The excitation through the IR photon originates from the vibrational ground state n = 0 which is not shown in the figure.

Beswick, J.A., Glass-Maujean, M., and Roncero, O. (1993). On the orientation of photofragments produced in highly excited rotational states, J. Chem. Phys. 96, 7514-7527. 

In product state spectra, the pump laser wavelength is fixed and the probe laser is scanned to obtain product rovibronic spectra. Analyses show how the product state distributions depend on the portion of the potential surface initially excited. Rotational state distributions of IlgHfX Z, V, N) were obtained using the A n,/2 <- X Z system. 

Radiation in the far (long-wavelength) infrared and microwave regions of the electromagnetic spectrum excites rotational states of molecules. In order to absorb radiation, the molecule must have a permanent dipole moment. Moreover, for a heteronuclear diatomic molecule, absorption of light is possible only between... 

Figure 1. Schematic representation of radiative recombination of an exciton bound to a neutral donor where the final state is the donor in the ground or in the excited configuration. The inset shows the initial state of the neutral-donor-bound exclton in the ground and several excited rotational states. (Reproduced with permission from Ref. 24. Copyright 1983 American Physical Society.)...

It must be mentioned that Ricehas postulated a different mechanism for the dissociation of a diatomic molecule. He assumes that only ordinary thermal collisions of molecules excited into extremely high vibrational states are responsible for the dissociation. The effect of the rotation is then only to increase the density of these excited states. We4 instead believe that the probability of the high-energy collisions and of the excited rotational states is comparable with that of the high vibrational excited states, and that all these probabilities must be added with the proper weight. 

He in the orbiting resonance is not spherical because of interference in the scattered waves from the I atom centers. And since 12 rotates very slowly, no individual resonance is subject to rotational averaging. Of course, all angles of approach of the atom to the I, and all impact parameters, are represented in the ensemble of resonances. Therefore, in addition to generating a force along the Ij bond, in any particular resonance the atom exerts different forces on the two I atoms when the vibrational transition is generated, excited rotational states of the relaxed are also... 

As a final note on numerical aspects in the three-dimensional model, we mention the availability of a complete set of computer routines for the calculation of rotational spectra and rovibrational interactions for triatomic molecules. These routines are quite complex because they must deal with matrix elements of the operators introduced in Section IV.D. In short, the practical calculations of rovibrational spectra of triatomic molecules can be rather demanding from a purely computational point of view, because of the large, complex matrices necessary to account for highly excited rotational states. 

Forrey, R.C., Cooling and trapping of molecules in highly excited rotational states, Phys. Rev. A, 63, 051403(R), 2001. 

The crossing between the ground and the first excited rotational states now occurs at 5 = For this particular value of the magnetic field, the matrix 4.11 can be... 

The improved finite element method gives accurate ground state eigenvalues with only a few elements. However, it still requires a fairly large mesh to accurately produce the highly excited rotational states. 

Ref. [21] at E Q ai = 0.50, 0.60, 0.70 and 1.183 eV. In all, 441330 trajectories were calculated, of which 8447 reacted. At all four eneigies it was found that reactant rotational eneigy is very effective in promoting the reaction and that the products are formed in highly excited rotational states [21]. This behaviour is similar to that discussed above for the CSDW cross sections at lower values of... 

Different standard radiation fields are found in the literature. We chose to take the values given by Mathis et al (1983) which extend from the ultraviolet to the far infrared. The chemical equilibrium and the populations of the excited rotational states of and HD are sensitive to the vacuum ultraviolet part of the radiation field (912 As A 2000 which is badly determined, whereas we have verified that the rotational excitation of Cj depends mainly on the red and infrared range corresponding to the radiative pumping in the Phillips band system. This red and infrared part of the radiation field is well constrained by photometric data and cannot be increased arbitrarily. 

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