The Fourier transform in infrared spectroscopy
The Fourier transform is a fundamental mathematical technique used in the field of signal analysis.
It makes it possible to decompose a complex signal into a series of sinusoidal components, thus revealing the different frequencies that make it up.
This theory finds significant application in infrared spectrophotometry.
In infrared spectroscopy, the Fourier transform is used to convert a time signal into a frequency spectrum. Concretely, it is used in the technique of Fourier transform infrared spectroscopy (FTIR), a powerful method for analyzing the chemical composition of samples.
When an infrared beam passes through a sample, certain wavelengths are absorbed by specific chemical bonds present in the substance. The detector then measures the intensity of the transmitted light at different wavelengths. The resulting signal is a complex temporal recording.
This is where the Fourier transform comes in. By applying this transformation, the signal in the time domain is converted into a spectrum in the frequency domain. This makes it possible to precisely identify the characteristic absorption frequencies of each chemical bond present in the sample.
The advantages of Fourier transform infrared spectrophotometry are numerous. First, it offers high spectral resolution, enabling the precise detection of functional groups. Additionally, this method is fast and provides results in real time. It is also non-destructive, meaning that the samples analyzed are not altered during the process.
Since its creation, the CNEP has used infra-red spectrophotometers with Fourier Transform in order to guarantee the precision and quality of our spectral analyses.
