Spectra and energy levels

Besides these differences in electronic energy levels and spectra, atomic spectroscopy differs from UV-VIS molecular spectroscopy in the following ways ... 

Dalton, B. J. (1971), Nonrigid Molecule Effects on the Rovibronic Energy Levels and Spectra of Phosphorous Pentafluoride, J. Chem. Phys. 54,4745. de Shalit, A., and Talmi, 1. (1963), Nuclear Shell Theory, Academic Press, N.Y. 

Use the dipolar Hamiltonian in Eq. 7.8 to compute the energy levels and spectra for the A part of an AX spin system. Ignore chemical shifts and indirect coupling. Use wave functions and other pertinent results from Chapter 6. 

Photophyskal Steps. The energy levels and spectra of these complexes have been described [13,28-30]. The ground, lowest quartet, and lowest doublet states are designated in Figure 1 with the pseudo-octahedral symbols. Excitation to T2 or to a higher quartet state is followed by rapid vibrational deactivation to the thermalized T2 or prompt intersystem crossing to the doublet manifold. With rare exceptions, E is below T2 and the emission is a narrow E => A2 spectrum. 

So far all we have said about energy levels and spectra applies to what are called weakly coupled spin systems. These are spin systems in which the differences between the Larmor frequencies (in Hz) of the spins are much greater in magnitude than the magnitude of the couplings between the spins. 

Theissing, H. H., and P. J. Caplan, Spectroscopic Calculations for a Multielectron Ion, Interscience-Wiley, 1966 (an exhaustive discussion of the energy levels and spectra of the Cr3+ ion). 

Figure13.1. Energy levels and spectra in ESR spectroscopy. A Energy levels for an unpaired electron in a magnetic field. B ESR absorption peak RF power (P) absorbed vs. magnetic field. C ESR first-derivative presentation—change of power absorbed per unit change in magnetic field vs. magnetic field. AH is the peak-to-peak line width. The first-derivative spectrum is the usual form obtained using ESR spectrometers, since phase-sensitive crystal detection of the microwave power absorbed by the sample is usually employed.

Musgtove, A., and R. Zalubas, 1985, Bibliography on Atomic Energy Levels and Spectra 1979-1983, NBS, Special Publication 363, suppl. 3 (U.S. Department of Commerce, Washington, DC) see also suppl. 1 and 2 this series. 

Hagan, L. Bibliography on Atomic Energy Levels and Spectra, July 1971 through June 1975, NBS-SP-363-Suppl. 1 [1977] C.A. 87 [1977] No. 109309. 

Experimental Techniques Evaluation of the Moments of Inertia Rigid-Rotor Energy Levels and Spectra Centrifugal Distortion Effects Rotation-Vibration Interactions Internal Rotation... 

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