Level anticrossing

Optical Nuclear Polarization (MI-ONP). Formal Equivalence of Microwave-Induced Level-Anticrossing Optical Nuclear Polarization. Extreme Values for Polarization. 

Level anticrossings between states with complex energies in the... 

The mechanism of the level-anticrossing is relatively well understood,... 

The level-crossing and anticrossing phenomena have been observed for the first time for hyperfine components of atomic energy levels.The level-anticrossing spectroscopy was then applied to the study of very weak singlet-triplet (or doublet-quadruplet) coupling in atoms" and in diatomic molecules (see, e.g.. Refs. 124 and 125 and references therein). 

The level-anticrossing techinque offers thus a unique possibility for detailed studies of electronic relaxation, because intramolecular parameters which determine the relaxation rate (the spacing of zero order ) and /) levels and of quasi-stationary a > and X) states, the mixing coefficients and vary in a well-defined way with the strength of the magnetic field. 

Level Anticrossing and Cross-Relaxation Effects A. The Level Anticrossing Experiment Cross-Relaxation Effects Microwave Studies Radiofrequency Studies Lifetime Measurements VI. Coherence Experiments A. The Rotating Frame Free Precession Spin Echoes... 

Fig. 16. Level anticrossing spectra of the lowest triplet states of 4,4 -difiuorobenzophenone, C-benzophenone, C-benzophenone, 4,4 -dichlorobenzophenone, and 4,4 -dibromobenzo-phenone in 4,4 -dibromodiphenylether with H at 1.6K. Asterisks denote weak satellites observed in the spectrum of DCBP (Mucha and Pratt, 1977b).

Fig. 17. Cross-relaxation model, which explains satellites observed in the level anticrossing spectra of triplet benzophenones in 4,4 -dibromodiphenylether. drawn approximately to scale for C-benzophenone with H z. The solid (dashed) arrows indicate field positions at which the triplet sublevel separations are equal to the Br ( Br) nuclear quadrupole frequencies of the host (Mucha and Pratt, 1977b).

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