- FTIR is based on the principle that molecules absorb specific frequencies of infrared light, resulting in characteristic vibrational transitions. - A sample is exposed to a broad spectrum of infrared light, and the transmitted or reflected light is analyzed.
- The key component is the interferometer, which splits the incoming infrared beam into two paths. - One beam travels through the sample, while the other travels through a reference. - The two beams are recombined, and the resulting interference pattern is analyzed using a Fourier transform to obtain the infrared spectrum.
- The resulting spectrum represents the absorption of infrared radiation at different frequencies. - Peaks in the spectrum correspond to specific vibrational modes of functional groups within the sample. - By comparing the obtained spectrum to reference spectra or databases, the chemical composition of the sample can be identified.
- FTIR is widely used in various scientific and industrial applications, including chemistry, biology, pharmaceuticals, food analysis, and material science. - It is valuable for identifying organic and inorganic compounds, determining molecular structures, and monitoring chemical reactions.
- Samples are typically prepared as thin films, pellets, or liquids to facilitate the transmission of infrared light. - Solid samples may be ground with a suitable matrix, and liquid samples can be placed in special cells.
- FTIR provides high-resolution spectra with improved signal-to-noise ratios. - It allows for rapid data collection and is non-destructive, making it suitable for a wide range of samples.
- Water vapor and other atmospheric gases can interfere with measurements, requiring careful sample handling. - Some materials may require special sample preparation or analysis techniques.