| As a kind of the interaction between light and material, the nature of Raman scattering is the inelastic collision of photons of the light and the electrons of the scattering material, which results in the change of the energy and the momentum of the incident photons. The scattered photons carrying the important informations of the molecular structure, chiefly the vibrational and rotational informations of the molecule, can be studied by Raman spectroscopy. So Raman spectroscopy has been playing an important role in the study of molecular structure. With the expansion of the frequency range of modern laser, the enrichment of light detection method and the increase of detection sensitivity, combining with other analytic method, Raman spectroscopy has been used in Physics, Chemistry, biology and material science.Nano-science and technology studies the motion laws, interactions and the application of the system which is composed by units whose size is among the range from 1 to lOOnm. Nano-particle means the fine particle in nano-scale. Different from bulk material, because the related-length of the electron wave-function is of the same magnitude, the electrons in nano-system can no longer be treated as classical particle. The dimension limit of nano-system also makes the electron states, the meta-exciton and the interactions different from the three-dimension system. Hence nano-material shows different properties with bulk one. The differences can be explained by quantum size effect, small size effect, surface effect and so on, which behave as special thermodynamic, electromagnetic and optical properties.This thesis consists of two part of work in spectral field: First, the spectral study of SnC>2 nano-particle.SnC>2 nano-particle was prepared by hydrothermal method. Annealed in different temperature we got SnO2 nano-particles whose size ranged from 4-80nm. The Raman spectroscopy and photoluminescence (PL) spectroscopy of these samples weremeasured. The experimental result shows that: (1) Compared with crystal SnO: the Raman band representing the rutile structure changed both its position and intensity. New Raman band appeared in SnC>2 nano-particles. We attribute the new band to the following factor: there are a large amount of defections, vacant positions, local crystal lattice disorder and the decrease of the spatial symmetry. (2) In the frequency range 1600-3600cm~' we find new Raman bands which have not been reported by other researcher before. We attribute it as the vibration of O-H and deduce the possibility that some oxygen atoms had been substituted by OH and there are HaO molecules adsorbed in the holes and the surface of SnCh nano-particles.(3) Crystal SnC>2 is transparent in the visible range without light emission and absorption. We observed a notable photoluminescence in SnC>2 nano-particle. With the decrease of particle size the frequency position and the intensity of the PL changed regularly. Our conclusion is that the PL is caused by the change of its energy band structure, including the exciton emission caused by quantum confine effect, the existence of defection energy level (additional energy level in the energy gap).Second, the Raman study of Phthalocyanine (Pc) compounds.Thin films of Phthalocyanine (Pc) compounds with different central atom (atoms) were prepared on silicon wafers. Raman spectrum was measured. Using a high sensitive CCD detector we reached high quality spectrum. A tentative bands assignment is made and the influence of different central atom (atoms) to the position and intensity of the Raman vibration is analyzed.
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