FourierTransformationsInfrarotspektrometer

Fourier Transform Infrared Spectroscopy, often abbreviated as FTIR, is an analytical technique used to identify chemical compounds. It works by measuring the absorption of infrared light by a sample. Infrared radiation causes molecular vibrations, and the specific wavelengths of light absorbed are unique to the chemical bonds present within the molecule. This creates a unique spectral fingerprint for each substance.

The core of an FTIR spectrometer is the interferometer. This device splits an infrared beam into two paths and then recombines them. One path contains a fixed mirror, while the other has a moving mirror. As the moving mirror travels, the path lengths of the two beams vary, causing constructive and destructive interference. This interference pattern, known as an interferogram, contains information about all the infrared frequencies simultaneously.

The interferogram is then processed using a mathematical operation called a Fourier transform. This transform converts the interferogram from the time domain (where signal intensity varies with mirror position) to the frequency domain, yielding the infrared spectrum. The resulting spectrum shows which infrared wavelengths were absorbed by the sample and at what intensity, allowing for identification and quantification of the compound. FTIR is widely used in chemistry, materials science, pharmaceutical research, and environmental monitoring due to its speed, sensitivity, and ability to analyze a wide range of samples.