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An infrared spectroscopy correlation table (or table of infrared absorption frequencies) is a list of absorption peaks and frequencies, typically reported in wavenumber, for common types of molecular bonds and functional groups.
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify ...
The vibrational frequencies of most molecules correspond to the frequencies of infrared light. Typically, the technique is used to study organic compounds using light radiation from the mid-infrared, 4,000–400 cm −1. A spectrum of all the frequencies of absorption in a sample is recorded.
Peak maxima for liquid water are observed at 3450 cm −1 (2.898 μm), 3615 cm −1 (2.766 μm) and 1640 cm −1 (6.097 μm). [14] Direct measurement of the infrared spectra of aqueous solutions requires that the cuvette windows be made of substances such as calcium fluoride which are water-insoluble.
Fourier transform spectroscopy is a less intuitive way to obtain the same information. Rather than shining a monochromatic beam of light (a beam composed of only a single wavelength) at the sample, this technique shines a beam containing many frequencies of light at once and measures how much of that beam is absorbed by the sample. Next, the ...
Two-dimensional infrared spectroscopy (2D IR) is a nonlinear infrared spectroscopy technique that has the ability to correlate vibrational modes in condensed-phase systems. This technique provides information beyond linear infrared spectra, by spreading the vibrational information along multiple axes, yielding a frequency correlation spectrum.
In spectroscopy, an absorption band is a range of wavelengths, frequencies or energies in the electromagnetic spectrum that are characteristic of a particular transition from initial to final state in a substance. According to quantum mechanics, atoms and molecules can only hold certain defined quantities of energy, or exist in specific states. [1]
At any given temperature, there is a frequency f max at which the power emitted is a maximum. Wien's displacement law, and the fact that the frequency is inversely proportional to the wavelength, indicates that the peak frequency f max is proportional to the absolute temperature T of the black body. The photosphere of the sun, at a temperature ...