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Ventacon Limited


Designed and optimised exclusively for
Fourier Transform Raman Spectrometers



Series H-15-200 Hot Cell

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 180C.

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 500C (more detail will be found in the Higher Temperature section below).

Two cells operating to 200C are offered by Ventacon. The Model H-15-200 is a cell designed to examine powders, liquids or lumps of sample. Solids are pressed into a 2.5mm diameter stainless steel cavity and compressed with a cylindrical piston. Powders or solids should, if possible, be pressed to measure 1-3mm in depth. If the sample is very thin the spectrum will be weak. Liquids are held in 5mm diameter NMR tubes or MPt tubes.