n-Nonadecane shows a phase transition from orthorhombic to so called a phase near 22.8·C and melts at 32°C. Temperature dependence studies of infrared and Raman spectra of n-nonadecane and of selectively deuterated nonadecanes (2D, and IOD,) allow one to obtain a detailed description of the structural changes which take place at the phase transition and melting. Experiments are interpreted on the basis of normal mode calculations. Comparison with the information available in the literature from other experiments or calculations shows that additional information are derived in this work. A model for the mechanism of phase transition is proposed.

The adsorption of 1,2,3-triazole on silver and gold colloidal nanoparticles is studied by means of surface enhanced Raman scattering (SERS). Further information about the adsorption mechanism on silver is obtained by recording the normal Raman spectra of the Ag(I)/1,2,3-triazole coordination compound. SERS data are interpreted with the help of density functional theoretical calculations of models of the ligand bound to silver or gold surface adatoms. 1,2,3-Triazole interacts with both silver and gold substrates in its anionic form through the lone pairs of the N 1 and N 3 atoms with a tilted orientation with respect to the metal surface.

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In this paper we report on the laser-excited Raman and luminescence spectroscopy of a series of ceria−zirconia mixed oxides, containing trivalent lanthanide ions as unintentional impurities, using 488.0-, 514.5-, and 1064.0-nm excitation wavelengths. We assigned the main bands located at Stokes shifts higher than 800 cm-1 from the laser lines to f−f emission transitions of Pr3+, Nd3+, Ho3+, and Er3+ ions. These ions can also be used as spectral probes of the cation sites in the solid solutions as their transition intensities are found to be dependent on the local symmetry of the sites in which they are accommodated. f−f emission transitions have also been found to overlap the vibrational Raman bands for Stokes shifts lower than 800 cm-1 from the laser lines. To overcome possible ambiguities in the structural information extracted from the Raman spectra, at least two laser excitation lines must be used.