Ventacon Hot Cell Systems provide users with the ability to heat solid, liquid or semi solid samples to elevated temperatures and to control the temperature of the sample precisely. It is not possible to raise temperatures to an unlimited extent. All hot samples emit black-body radiation and do so more and more as the temperature increases. The emission follows a well characterised profile whose maximum decreases in wavelength with increasing temperature. As a consequence, FT Raman users see a background whose intensity rises to increasing wavenumber shifts and the problem becomes dramatically worse as the temperature increases. It is therefore not feasible to measure complete FT spectra much above 180°C.
Spectroscopists with CCD/Dispersion instruments use
lasers emitting in the visible and deep red. In these experiments,
interference from black-body radiation is much less of a nuisance
than in FT Raman Spectrometry. As a result much higher temperatures
are accessible and Ventacon provides cells operating up to 300 and
even 500°C (more detail will be found
in the Higher Temperature section below).