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Infrared and Raman spectra are reported for 10 complexes of rare earth nitrate with Schiff base from o-vanillin (2-hydroxy-3-methoxy-benzaldehyde) and 1-naphthylamine in the range 100–4000 cm −1 and 100–1799 cm −1 . Some absorption bands are assigned and the results of them are used to discuss the coordinated structure of the complexes.

Coordination compounds of rare earth chlorides with Schiff base derived from vanillin (3-methoxy-4-hydroxy-benzaldehyde) and 2-naphthylamine have been prepared and characterized. The general formula of the coordination compounds, [LnL2Cl2(H20)2] Cl H20 (where Ln - La, Ce, Pr, Nd, Eu, Gd, Dy, Ho, Tm, Lu; L = Schiff base), are based on the elemental analyses, infrared spectra, ultraviolet spectra, Raman Spectra, Molar conductance and thermal analyses.

The pressure dependences of the Raman-active graphite layer shearing modes in highly oriented pyrolytic graphite (HOPG) and FeCl3-HOPG acceptor intercalation compounds for stage indices n=1, 2 and 3 have been measured in diamond anvil cell by use of a Spex-1403 Ramalog system. The results of high-pressure Raman spectra show that both the interior and neighbouring modes exhibit a frequency shift upwards with increasing pressure, which has been attributed to an in-plane lattice contraction. In stage-3 FeCl3-HOPG, the pressure-induced staging transition from stage 3 to stage 4 has been found from the change in intensity ratio of the interior to neighbouring modes at 8.39 GPa. This finding confirmed firstly that the pressure-induced staging transitions are not just confined to the alkali-metal graphite donor intercalations but are valid for the acceptor graphite intercalation compounds.

High pressure Raman spectra of Melamine (C3H6N6) have been studied up to 8.7 GPa. The pressure effect on Raman spectra reveals that the discrepancy between intra and inter-molecule bonds tends to shrink with increasing pressure. The experimental results show that Melamine probably undergoes two structural transitions at 2 and 6 GPa respectively and the structure of the new phase has C1 1 i symmetry probably at 2GPa

Raman spectra of liquid and crystalline CHCl3 and CHBr3 have been measured at pressures up to 102 kbar and room-temperature. The pressure dependences of the internal modes (for CHCl3 and CHBr3) and the external modes (for CHBr3) are reported. The results for CHCl3 show that all of the E modes (ν4, ν5, ν6) are split into two peaks at the liquid-solid phase transition point (7.9 kbar). Another phase transition is suggested by the discontinuities of the internal mode slopes (dν/dp) at about 60 kbar. For CHBr3, three pressure-induced phase transitions were observed: the one at 3.3 kbar is a liquid-solid phase transition (liquid to α), and the other two at 8.0 kbar (α to β) and in the range 51.5–95 kbar (β + γ), respectively, are solid-solid phase transitions. The pure γ phase is obtained at above 95 kbar. Comparison of the spectra at high pressure and 293 K with that at low temperature and 1 bar indicates their structures are similar.