The combined inVia Raman and IlluminatIR? FT-IR spectrometer
The IlluminatIR? is a modular FT-IR spectrometer from SensIR Technologies, which may be easily mounted beneath the eyepieces of the research grade, infinity corrected, microscope of Renishaw?s inVia instrument (Fig. 1). This enables users to retain full use of the range of optical techniques available with the Leica? DMLM microscope.
The IlluminatIR? is commonly used with either a diamond contact ATR (attenuated total reflection) or a diffuse reflectance objective. The sample can be viewed, and Raman spectra collected, either through these objectives or through the high quality microscope objectives supplied with the inVia Raman microscope. Simple switching between video view, IR acquisition, and Raman acquisition allows IR and Raman spectra to be acquired sequentially from the same spot on the sample; this switching is fully software controlled on the inVia Reflex instrument.
This document will briefly explain the benefits of combined Raman and FT-IR analysis, and introduce some of the major application areas.
Infrared and Raman spectroscopy
Infrared (IR) absorption and Raman scattering are both commonly used to study and identify substances using the Vibrations with a large change in dipole moment or polarisability lead to stronger coupling between the photons and the vibrational transitions and hence give stronger IR absorption or Raman scattering, respectively. Therefore, groups such as carbonyls and nitriles give strong IR absorption, while aromatic rings and unsaturation lead to intense Raman bands.