how to do atr correction using essential ftir

What makes infrared absorption spectroscopy even more useful is the fact that it is capable to analyze all gas, liquid and solid samples. Most molecules are infrared active except for several homonuclear diatomic molecules such as O 2, N 2 and Cl 2 due to the zero dipole change in the vibration and rotation of these molecules.

Therefore, by analyzing the infrared spectrum, one can readily obtain abundant structure information of a molecule. The intensity of absorption peaks is related to the change of dipole moment and the possibility of the transition of energy levels. The number of absorption peaks is related to the number of vibrational freedom of the molecule. The frequency of the absorption peak is determined by the vibrational energy gap. Consequently, the vibrational energy levels of sample molecules transfer from ground state to excited state. When exposed to infrared radiation, sample molecules selectively absorb radiation of specific wavelengths which causes the change of dipole moment of sample molecules. Infrared spectrum is molecular vibrational spectrum. Infrared absorption spectroscopy is the method which scientists use to determine the structures of molecules with the molecules’ characteristic absorption of infrared radiation. Since then, scientists have established various ways to utilize infrared light.

The discovery of infrared light can be dated back to the 19th century. The range of Infrared region is 12800 ~ 10 cm -1 and can be divided into near-infrared region (12800 ~ 4000 cm -1), mid-infrared region (4000 ~ 200 cm -1) and far-infrared region (50 ~ 1000 cm -1).

How to do atr correction using essential ftir