Strong-coupling effect

The H spectra of both compounds show all facets of spectral appearance, well resolved spectral regions as well as regions with heavy signal overlap and simple first order multiplets as well as complex multiplet structures caused by strong coupling effects. 

The present analysis relies on - and extends - the comprehensive theoretical study of Refs. [23,24] on the multi-state interactions in the manifold of the X — E states of Bz+. Like this recent work, it utilizes an ab initio quantum-dynamical approach. In Refs. [23,24] we have, in addition, identified strong coupling effects between the B — C and B — D electronic states, caused by additional conical intersections between their potential energy surfaces. A whole sequence of stepwise femtosecond internal conversion processes results [24]. Such sequential internal conversion processes are of general importance as is evidenced indirectly by the fluorescence and fragmentation dynamics of organic closed-shell molecules and radical cations [49,50]. It is therefore to be expected that the present approach and results may be of relevance for many other medium-sized molecular systems. 

P. Pfaendler, G. Bodenhausen, Strong Coupling Effects in z-Filtered 2-D NMR Correlation Spectra, J.Magn.Reson., 72, (1987), 475-492. 

FACTORS THAT INFLUENCE THE SIGN AND MAGNITUDE OF/ SECOND-ORDER (STRONG) COUPLING EFFECTS... 

SLANTING MULTIPLETS AND SECOND-ORDER (STRONG COUPLING) EFFECTS 145... 

There is a common misconception that strong coupling effects need not be considered at higher field, because accidental chemical equivalences or near equivalences are much less likely to occur than at lower magnetic fields. Of course, that is true. However, symmetric, not accidental, chemical equivalence is the basis for the effect shown in Fig. 6.13[Pg.175]

In which of the following molecules are strong coupling effects of the type illustrated in Fig. 6.13 likely to appear at high magnetic field ... 

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