Raman, infrared, and surface-enhanced Raman spectroscopies were applied to the vibrational characterization of the most stable conformer of the 10-isopropyl-10H-phenothiazine-5-oxide derivative. To find the optimized structure and the computed vibrational wavenumbers of the title compound, ab initio calculations at the Hartree−Fock level of theory and density functional theory calculations at the BPW91 and B3LYP levels of theory were performed. The comparison of the surface-enhanced Raman (SER) spectra, obtained only on activated silver colloids, with the corresponding Raman spectra reveals small shifts (Δν ≤ 5 cm-1) and proves the partial chemisorption of the molecules on the silver surface via the lone pair electrons of the oxygen atom; the electromagnetic mechanism is the main mechanism of the enhancement. Variations of the SER spectra with the change of pH were attributed to the orientational changes of the adsorbed molecules with respect to the silver surface.

Fourier transform (FT) Raman and surface-enhanced Raman spectroscopy (SERS) were applied to the vibrational characterization of isoquinoline and 4-methylquinoline. The assignment of the vibrational modes was carried out on the basis of results obtained from density functional theory calculations. The comparison of SER spectra with the FT-Raman spectra reveals remarkable changes attributed to the chemical interaction between the molecules and the silver substrate. The SER spectra of the adsorbed molecules depend strongly on the pH conditions. Variation in SER spectra with change of pH is attributed to a change in orientation of the absorbed isoquinoline molecules with respect to the silver surface and to a change in the chemical nature of the 4-methylquinoline molecules.

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Lithiation of triphenyl((trimethylsilyl)imino)phosphorane, Ph 3 PdNSiMe 3 (1), with MeLi gives the ortho-metalated species [Li(o-C 6 H 4 PPh 2 NSiMe 3 )] 2 ‚Et 2 O (2). It has all the requirements of an organometallic ligand capable of sidearm donation: the deprotonated ortho phenyl carbon atom leads to metal-carbon σ bonds in reactions with metal halides, and the Ph 2 PdNSiMe 3 moiety donates an electron pair to that metal via the imine nitrogen atom. In reactions with InCl 3 the In(III) organometallic complex [In(o-C 6 H 4 PPh 2 NSiMe 3 ) 3 ] (3) was obtained, while with FeCl 2 a new example of the rare iron(II) 14-VE complexes [Fe(o-C 6 H 4 -PPh 2 NSiMe 3 ) 2 ] (4) was obtained. Reaction of 2 with Ph 3 GeCl gave [Ph 3 Ge(o-C 6 H 4 PPh 2 -NSiMe 3 )] (5). While in 4 both imino sidearms coordinate to the metal, because of steric crowding only two of the three present coordinate in 3. Because of the low Lewis acidity of the tetraorganogermanium moiety the imino sidearm does not donate to the central germanium atom in 5.

The Raman spectrum of 2-formylfuran in the liquid phase shows pairs of bands whose temperature and solvent dependence behavior can be interpreted in terms of cis-trans conformational equilibrium. Density functional theory (DFT) calculations performed at the BPW91/6-311+G * and B3LYP/6-311+G * theoretical levels show that the trans-isomer is more stable than the cis-isomer by 2.81 and 3.12 kJ mol −1 , respectively. The theoretical 1H values obtained at these theoretical levels [2.99 kJ mol −1 (BPW91) and 3.2 kJ mol −1 (B3LYP)] are very close to the experimental value 1H = 2.52 kJ mol −1 determined from the plots of logarithmic relative intensities of the band pairs 1673/1692, 1477/1465 and 1396/1371 cm −1 of these isomers against reciprocal temperature. The surface-enhanced Raman spectrum of 2-formylfuran in silver colloid suggests the chemisorption of this molecular species on the silver surface both through the ring oxygen and the oxygen atom of the substituent group, the cis-form being preferred in the adsorption state. The adsorbed molecules are oriented perpendicular or least tilted with respect to the silver surface.