The following table lists infrared spectroscopy absorptions by frequency regions.

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.

This article will provide a table containing IR spectrum absorbtion frequency values and what they represent.

2023年2月11日 · Table of Common IR Absorptions. Note: strong, medium, weak refers to the length of the peak (in the y axis direction). Note: spectra taken by ATR method (used at CSB/SJU) have weaker peaks between 4000-2500 cm -1 compared to reference spectra taken by transmittance methods (typical on SDBS and other sites).

Table 1. Characteristic IR Absorption Peaks of Functional Groups* * Abbreviations: s = strong; m = medium; w = weak; br = broad; sat. = saturated; conj. = conjugated ** Alcohols, Esters, Carboxylic Acids, and Anhydrides also absorb in the fingerprint region due to the C-O stretch (1300 – 1000, s). Table 2.

The carbonyl stretching absorption is one of the strongest IR absorptions, and is very useful in structure determination as one can determine both the number of carbonyl groups (assuming peaks do not overlap) but also an estimation of which types.

IR peaks are not 100% reliable. Peaks tend to be stronger (more intense) when there is a large dipole associated with a vibration in the functional group and weaker in less polar bonds (to the point of disappearing in some completely symmetrical bonds). There are also weak overtone bands between 1660 and 2000, but are not shown here.

1100-1300 cm -1 (two bands - distinction to ketones, which do not possess C-O!) The absorptions in this range do not apply only to bonds in organic molecules. IR spectroscopy is useful when it comes to analysis of inorganic compounds (such as metal complexes or …

Table of Characteristic IR Absorptions m=medium, w=weak, s=strong, n=narrow, b=broad, sh=sharp frequency, cm –1 bond functional group 3640–3610 (s, sh) O–H stretch, free hydroxyl alcohols, phenols 3500–3200 (s,b) O–H stretch, H–bonded alcohols, phenols

FT-IR Spectroscopy; IR Absorption Frequencies ; Typical IR Absorption Frequencies For Common Functional Groups. Bond Functional Group Frequency in cm −1 (Intensity*) C–H: Alkane: 3000–2850 (s) –CH 3: 1450 and 1375 (m)