Splitting-, resonance

The resonance splitting of intramolecular modes in the crystalline state is often called Davydov splitting or factor group splitting . In contrast to the static field effects of the crystal, this splitting is due to the dynamical interaction of the constituents in the primitive cell... 

Smaller values of the activation free energy due to (i) the distortion of the shape of the free energy surfaces and (ii) the increase of the resonance splitting, AJF, of the potential free energies for the classical subsystem due to the increased overlapping of the wave functions of the quantum particles. 

Resonance splitting, 38 447 Resonantly enhanced multiphoton ionization (REMPI),46 147... 

Chandross and Ferguson64 find that the absorption spectra of dimers, produced65 by photolytic cleavage of photodimers of anthracene and mono-derivatives in a rigid methylcyclohexane glass at 77°K, are consistent with a symmetrical sandwich configuration these dimers also emit the characteristic excimer fluorescence. On the other hand, it is necessary to assume a 60° rotation of one component about the intermolecular axis of the 9,10-di-chloroanthracene dimer (as in the crystalline compound) to account for the observed resonance splittings of both absorption bands.64... 

However, off-resonance multiplets are distorted, in that the multiplet lines on the side of the decoupling frequency are weaker than those on the opposite side. Further, off-resonance splittings of higher than first order may be observed for substructures such as... 

The carbon chemical shifts are assigned on the basis of the off-resonance splitting pattern and additivity principles and is... 

Both were recorded over 5000 Hz range in DMSO-dg on FT 80, 80 MHz NMR spectrometer, using 10 ml sample tube, and tetramethylsllane as reference standard at ambient temperature. The carbon chemical shifts assigned on the basis of additivity principle and off-resonance splitting pattern are given in Table 3. 

ABX See (35) Similar to AA X but with small (8a-8b) (typically 0.03 ppm) due to isotope shift Six-line multiplet similar to AA X, but with central resonance split see Fig. 13... 

Steric complications arise when the acceptor together with C2 forms a nine-membered ring. Hafner and coworkers88 89 have studied 10,10-bis(dimethylamino)methylene cyclo-nonatetraene (40) and found that the compound participates in a solvent-dependent equilibrium between a twisted form with low polarity (40a, Amax = 330 nm), favored by nonpolar solvents, and a nearly planar dipolar form (40b, Amax = 403 nm), favored by polar solvents and low temperature. The N—CH3 resonance splits into a doublet... 

A nucleus or group of nuclei coupled to a set of n nuclei with spin / will have its resonance split into 2nl + 1 lines. For the common case of / = y2, there... 

The V2 vibration will be observed as a doublet due to Fermi resonance splitting, a process that can occur if an overtone or combination energy level happens to fall near the energy level of a fundamental vibration and if both levels have the same symmetry. The frequency can be taken as the mean of the doublet peaks. From your values of v, V2, and v, deduce which combination band is involved in the Fermi resonance with v. ... 

The methods of geometrical analysis described are only a very rough solution because the intersection of the potential energy surfaces is not identical with the energy profile of the reaction path. Considerations of resonance splitting of potential energy surfaces in the transition complex range lead to further refinement [25-27],... 

F nuclear magnetic resonance data there is basically one resonance, split into a doublet Jp. = 585 c.p.s. S (from external trifluoroacetic acid reference) = — 44 p.p.m. (The checkers report 579 and —44.2, respectively.) Further splitting is due to coupling between fluorine atoms and protons of the alkyl groups. 

Fig. 9.2. Cartoon illustrating changes in the light scattering spectra when two noble metal nanoparticles are brought into close proximity to each other. The plasmon resonance splits into longitudinal and transverse modes, with scattering from the longitudinal mode more intense. This can be used as the basis for a plasmon ruler with application in single molecule biophysics...

The methyl resonance of the complex is a sharp singlet above -50°C. Below —72°C, the resonance splits reversibly into two peaks of not quite the same intensity. If the nitrogen molecule is doubly labeled with N, the H-decoupled N spectrum contains a sin-... 

Sn—Me resonance splits up into two resonances at positions of the pure compounds. Moreover, at this temperature the NMe2 and NCH2 resonances start to split up, which indicates that under these conditions the tin center is becoming configurationally stable on the NMR time scale. 

EI8.10 The structure of XeOFT is shown below. The e-NMR would consist of one resonance split into a 1 3 3 1 quartet due to the coupling to three equivalent F nuclei. 

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