IR Spectrum Analysis Steps: Decoding Information from Spectra to Compounds

Infrared spectroscopy is a common analytical tool that helps scientists determine the structure and function of compounds. By analyzing infrared spectra, we can understand the presence and type of functional groups and chemical bonds in the compounds. This article will detail the steps of infrared spectroscopy analysis, helping readers to better understand and interpret infrared spectra.

 

Obtain Infrared Spectrum

Before performing infrared spectroscopy analysis, the first step is to obtain the infrared spectrum of the compound to be analyzed. This can be achieved using an infrared spectrometer. The infrared spectrometer emits infrared light into the sample to be analyzed, then measures the sample's absorption of light at different wavelengths. Through this process, we can obtain an infrared spectrum.

 

Observe the Overall Shape of the Spectrum

Once we have obtained an infrared spectrum, we first need to observe the overall shape of the spectrum. Infrared spectra are typically plotted with wavenumber as the x-axis and absorption intensity as the y-axis. We can note the absorption peaks and absorption bands in the spectrum. Absorption peaks generally indicate the presence of specific functional groups, while absorption bands signify the presence of chemical bonds.

 

Determine the Positions of Absorption Peaks

Next, we need to determine the positions of the absorption peaks in the infrared spectrum. Different functional groups and chemical bonds have specific absorption positions in infrared spectra. By comparing the infrared spectra of known compounds with that of the compound to be analyzed, we can initially determine the positions of the absorption peaks.

 

Interpret the Intensity of Absorption Peaks

In addition to the position of absorption peaks, the intensity of absorption peaks is also an important piece of information in infrared spectroscopy analysis. The intensity of absorption peaks can reflect the content of specific functional groups or chemical bonds in the compound. By comparing the intensities of absorption peaks, we can infer the relative contents of different functional groups or chemical bonds in the compound.

 

Analyze the Shape of Absorption Bands

In addition to absorption peaks, the absorption bands in infrared spectra also provide important information. The shape of absorption bands can help us determine the type of chemical bonds. For example, C=O bonds usually manifest as a sharp absorption band, while -OH bonds appear as a wide and flat absorption band.

 

Analyze the Compound by Combining the Above Information

By observing the position, intensity, and shape of absorption peaks and bands in the infrared spectrum, we can gradually analyze the structure and function of the compound. By comparing the infrared spectrum of the compound to be analyzed with known infrared spectral databases, we can find similar spectra and thus determine the structure and function of the compound.

 

Infrared spectroscopy analysis is an important method in chemical analysis, helping scientists determine the structure and function of compounds. By observing the position, intensity and shape of absorption peaks and bands in an infrared spectrum, we can analyze the information about the compound. Hope this article helps readers understand the steps of infrared spectroscopy analysis, and be able to better interpret infrared spectra in practical applications.