Development and applications of a dispersive Raman spectrometer
The opening section describes the development of the instrument from an existing Raman spectrometer operating in the visible region with Ar-ion laser excitation. In the first part of this section the steps carried out to improve the performance of the visible Raman system are outlined. In the second part, the development of the near-IR Raman system is described. The near-IR region was used because the radiation in this region has insufficient energy to induce a molecular transition to an electronically excited state and hence cause fluorescence. The system comprised of a Nd-YAG laser as a source in conjunction with a Ge detector. In the third part, the computer programs written to increase the capabilities of the data manipulation software are described. In the second section, a comparison is made of the near-IR system with Fourier Transform Raman spectroscopy, this being the most widely used technique used today to overcome the fluorescence problem. A wide range of samples were investigated and conclusions drawn concerning the future applicability of the near-IR dispersive technique. The third section describes the applications of the dispersive system: (a) to study the complexing of BBr3 with (i) PBr3 and (ii) P4S3; (b) to study, in conjunction with IR spectroscopy, the complexing of Me2SnCl2 with a range of pyridine and quinoline derivatives.