Electron parametric resonance

In impulsive multidimensional (1VD) Raman spectroscopy a sample is excited by a train of N pairs of optical pulses, which prepare a wavepacket of quantum states. This wavepacket is probed by the scattering of the probe pulse. The electronically off-resonant pulses interact with the electronic polarizability, which depends parametrically on the vibrational coordinates (19), and the signal is related to the 2N + I order nonlinear response (18). Seventh-order three-dimensional (3D) coherent Raman scattering, technique has been proposed by Loring and Mukamel (20) and reported in Refs. 12 and 21. Fifth-order two-dimensional (2D) Raman spectroscopy, proposed later by Tanimura and Mukamel (22), had triggered extensive experimental (23-28) and theoretical (13,25,29-38) activity. Raman techniques have been reviewed recently (12,13) and will not be discussed here. 

CD = circular dichroism CCD = charge coupled device EPR = electron paramagnetic resonance FTIR = fourier transform infra-red FWHM = full width (at) half maximum MCD = magnetic circular dichroism MLCT = metal-to-ligand charge-transfer NMR = nuclear magnetic resonance OPOs = optical parametric oscillators PSII = photosystem 11. 

This has been developed since 1986. The title letters stand for Localized Delocalized Response. The localized effect is Charton s preferred name for the inductive effect and delocalized effect is his preferred name for the resonance effect. Indeed, he would like to change the usual symbols from <7/ to 0/, and or to op for the purposes of the Extended Hammett (EH or LD) equation109. The response referred to is that of the substituent to the electronic demand of the site (i.e. reaction site in the correlation analysis of reactivity). Thus this equation, like the PSP equation, is concerned with the parametrization of substituent polarizability. 

The term has been deemed obsolescent or even obsolete (see mesomeric effect, resonance effect). Many have used phrases such as enhanced substituent resonance effect that imply the operation of the electromeric effect without using the term, and various modern theoretical treatments parametrize the response of substituents to electronic demand, which amounts to considering the electromeric effect together with the INDUCTOMERIC EFFECT. 

The scattering matrix elements implicitly depend on x via the parametric coordinate dependence of Edot and F. The tunnel coupling F homogeneously broadens the resonance energy levels E t- Therefore, the Lorentzian distribution of the scattering matrix element implies an exponential decay via the coupling of electrons to the environment across only a resonance window of density of states p(E)... 

Thus, In the vicinity of a shape resonance, the electronic transition moment varies rapidly with R. This parametric coupling was estimated In the adlabatlc-nuclel approximation by computing the net transition moment for a particular vibrational channel as an average of the R-dependent dipole amplitude, weighted by the product of the Initial- and final-state vibrational wavefunctlons at each R (40.43). 

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