Espectroscopia FTIR: Análise de Vibrações Moleculares

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FTIR spectroscopy:
FTIR, or Fourier transform infrared spectroscopy, is a technique used to analyze the molecular vibrations of a sample by measuring the absorption or transmission of infrared radiation through the sample. It is a powerful analytical tool that can provide information about the chemical composition, structure, and functional groups of a wide range of materials, including solids, liquids, and gases.
FTIR works by passing an infrared beam through a sample, and measuring the intensity of the transmitted or reflected light as a function of the wavelength of the infrared radiation. The resulting spectrum provides a unique “fingerprint” of the sample’s molecular vibrations, which can be used to identify the sample and determine its chemical composition.
In FTIR, the infrared radiation is first directed onto an interferometer, which splits the radiation into two beams. One beam passes through the sample, while the other passes through a reference material. The two beams are then recombined, and the resulting interference pattern is analyzed to determine the absorbance or transmission of the sample.
The resulting spectrum shows the absorbance or transmission of the sample as a function of the wavelength of the infrared radiation. The peaks in the spectrum correspond to specific molecular vibrations of the sample, which can be used to identify the chemical composition of the sample. For example, the position and shape of the peaks can provide information about the functional groups present in the sample, such as carbonyl, hydroxyl, or amine groups.
FTIR is a non-destructive technique that can be used to analyze samples in their native state, without the need for preparation or modification. It is widely used in materials science, chemistry, and biology, and has applications in fields such as pharmaceuticals, polymers, food science, and environmental analysis.