Saturation excitation profiles

Soft-pulse multiple irradiation In this method, pre-saturation is done using shaped pulses having a broader excitation profile. Therefore, it is a more suitable method for the suppression of multiplets. This technique is very effective, easy to apply and easy to implement within most NMR experiments. In aqueous solutions, however, slowly exchanging protons would be detectable due to the occurrence of transfer of saturation. In addition, the spins with resonances close to the solvent frequency will also be saturated. 

Saturation Broadening in Flames and Plasmas As Obtained by Fluorescence Excitation Profiles... 

Direct Measure- ment Fluorescence "" Excitation Profile Saturation Broadening ... 

The details of the mechanism of decay of states in alkanes retain their interest. The effect of deuterium on fluorescence lifetimes has been discussed in terms of the theory of radiationless transitions. Analysis of fluorescence line shapes and Raman excitation profiles of tetradesmethyl-p-carotene in isopentane has been carried out at 190 and 230K . Solvation occurs over a time scale of about 100 fs whilst vibrational relaxation has a time scale of about 250 fs. The kinetics of the interaction of alcohols with the excited state of triethylamine shows involvement of a charge transfer exciplex . Ionizing radiation is a means of exciting saturated hydrocarbons and the complexity of three component systems containing saturated hydrocarbons, aromatic solvent, and fluorescent solute has been examined. ... 

Partial saturation of the HO absorption and use of excitation line widths wider than the HO absorption line width are in general undesirable, because they may produce spurious HO while exciting HO fluorescence with less than 100% efficiency (103). However, the issue is not as simple as matching the HO absorption profile exactly and avoiding all saturation. For instance, a matched laser excitation line width is more difficult to achieve and to keep tuned to the HO absorption, and the... 

Fig. 8.14 a Differential absorption spectra (visible and near-infrared) obtained upon femtosecond flash photolysis (387 nm) of 6b in nitrogen-saturated THF solutions with a time delay of 3000 ps at room temperature, indicating the fullerene Triplet-triplet features, b Time-absorption profiles of the spectra shown above at 500 and 705 nm, monitoring the decay of the singlet excited-state and formation of the triplet excited state... 

Spatial density profiles of atomic (and molecular) species can also be made via saturation fluorescence approaches. For a "2-level" atom, like Sr, a plot of 1/Bp vs 1/E (Bp is the fluorescence radiance, in J s 1m-2sn l, and Ex is the excitation spectral irradiance, in J s nT nm ) allows estimation of the quantum efficiency, Y of the fluorescence process (and thsu estimation of "radiationless" rate constants) and the total number density nj, of the species of interest by means of... 

The quantum yield of the photodissociation was estimated by using the excitation dependence of the diffraction efficiency from the anharmonic thermal grating (section III.F.l) created by a saturated absorption [116,117], The rate constant of the nongeminate recombination of photo-dissociated iodine in solution was extracted from the temporal profile of the TG signal. 

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