Vibrational mode shifts

The lower spectrum corresponds to heavier NFP doping. The aromatic C=C and C=N vibration modes shifted to higher Trequency, from 1595 cm" for pristine PMQ3 to 1617 cm" for heavily doped PMQ3. The same phenomenon was also observed in iodine doped PMQ3, where the band shifted to 1610 cm" (Figure 8). This is attributed to an increase of the force constant for C=C and C=N bonds due to complexation with the acceptors. ... 

In accordance with the mixing of the guest-host modes, the presence of the guest hardens the mode and the host vibrational modes shift toward higher frequency region. This is viewed from the densities of state plotted in Fig. 3, where Hessian matrices for empty and filled with spherical propane are diagonalized. (For the... 

Single surface calculations with a vector potential in the adiabatic representation and two surface calculations in the diabatic representation with or without shifting the conical intersection from the origin are performed using Cartesian coordinates. As in the asymptotic region the two coordinates of the model represent a translational and a vibrational mode, respectively, the initial wave function for the ground state can be represented as. 

Raman spectroscopy is particularly useful for investigating the structure of noncrystalline solids. The vibrational spectra of noncrystalline solids exhibit broad bands centered at wavenumbers corresponding to the vibrational modes of the corresponding crystals (Figure 5). In silicate glasses shifts in the high-wavenumber bands... 

While the BC configuration for the B—H complex is now accepted, several aspects of the vibrational spectra of the acceptor-H complexes are not understood. The temperature dependence of the B—H complex has been examined by Raman spectroscopy (Stutzmann and Herrero, 1987) and IR absorption (Stavola et al., 1988a). The H-stretching vibration shifts from 1875 to 1903 cm 1 between room temperature and liquid He temperature. Frequency shifts of just a few cm 1 are more typical for local vibrational modes. The vibrational bands are also surprisingly broad. 

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