Circular Attenuated Total Reflection CATR

The mechanical simplicity of an FTIR spectrometer contrasts sharply with its theoretical complexity. The only moving part is the mirror, which rides on air or mechanical bearings to facilitate maintenance and improve reliability. The round cross-section of the FTIR beam is especially advantageous in situations where a circular attenuated total reflectance (CATR) accessory for liquids is used. For heat-sensitive compounds it is important to note that the sample is not heated significantly during the FTIR measurement. 

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