IR Spectroscopy Instrumentation

IR spectroscopy instrumentation is used to elucidate what groups are present in a sample.

The IR radiation band comprises wavelengths of 800-1,000,000 nanometers. This light is invisible to the human eye, although the effects of IR radiation are felt as heat.

The radiation range used in IR spectroscopy instrumentation is 2,500-16,000 nanometers. This range is called the group frequency region.

Chemical bonds in a molecule can be made to stretch, bend or twist when exposed to IR radiation. This occurs at a wavelength that is unique for each bond and each type of vibration.

Therefore, the presence of a specific bond is characterized on an IR spectrum by the absorption of radiation at a discrete set of wavelengths.

Conventional IR spectroscopy instrumentation requires a source of radiation, a container for the sample and IR sensors to detect which wavelengths have passed through the sample.

The traditional IR spectrometer is called a dispersive grating spectrometer. This works by dividing the radiation from the IR source into two streams, with one stream passing though the sample and the other being used as a control.