Related Experiment Video

Updated: Jun 12, 2026

Improving Infrared Spectroscopy Characterization of Soil Organic Matter with Spectral Subtractions
08:57

Improving Infrared Spectroscopy Characterization of Soil Organic Matter with Spectral Subtractions

Published on: January 10, 2019

Infrared measurements of increased CF(2)Cl(2) (CFC- 12) absorption above the South Pole

C P Rinsland, A Goldman, F J Murcray

    Applied Optics
    |June 5, 2010
    PubMed

    More Related Videos

    Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers08:51

    Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers

    Published on: August 18, 2017

    Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy07:49

    Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy

    Published on: February 20, 2020

    Related Concept Videos

    IR Frequency Region: Fingerprint Region01:03

    IR Frequency Region: Fingerprint Region

    IR spectra are divided into two main regions: the diagnostic region and the fingerprint region. The diagnostic region of the spectrum lies above 1500 cm−1. The absorptions resulting from single-bond vibrations of the N–H, C–H, and O–H stretch at higher wavenumbers and appear on the left side of the spectrum. The stretching absorptions of the C≡C and C≡N occur between 2100–2300 cm−1. In contrast, those arising from stretching absorptions of the C=O, C=N, and C=C occur between 1600–1850 cm−1.
    The...
    IR Spectrum Peak Intensity: Amount of IR-Active Bonds00:55

    IR Spectrum Peak Intensity: Amount of IR-Active Bonds

    When infrared radiation is passed through a molecule, absorption occurs if the molecule's vibration leads to a substantial change in its bond dipole moment. Transitions between vibrational energy levels, typically corresponding to infrared frequencies (4000–400 cm−1), allow absorption if the vibration significantly alters the dipole moment, making the molecule infrared active. The molecular bonds have different stretching and bending vibrations, resulting in various peaks with varying...
    IR Frequency Region: Alkene and Carbonyl Stretching01:29

    IR Frequency Region: Alkene and Carbonyl Stretching

    Double bonds in alkenes and carbonyl compounds exhibit stretching frequencies in the diagnostic region of the IR spectrum. In addition, alkenes exhibit vinylic C–H stretching and C–H out-of-plane bending absorptions that are useful for identifying substitution patterns.
    Stretching frequencies are affected by several factors, such as resonance, inductive effects, ring strain, dipole moment, and hydrogen bonding. Consequently, the stretching frequency of the carbonyl double bond varies in...
    IR Spectrum Peak Intensity: Dipole Moment01:20

    IR Spectrum Peak Intensity: Dipole Moment

    The dipole moment of a bond is the product of the partial charge on either atom and the distance between them. Dipole moments influence the efficiency of IR absorption and the peak intensity. When a bond with a dipole moment is placed in an electric field, the direction of the field determines if the bond is compressed or stretched. Electromagnetic radiation consists of an electric field component that rapidly reverses direction. It follows that polar bonds are alternately stretched and...
    Spectroscopy of Carboxylic Acid Derivatives01:26

    Spectroscopy of Carboxylic Acid Derivatives

    Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and unsymmetrical carbonyl vibration.
    In the...
    IR Spectrum01:19

    IR Spectrum

    When infrared (IR) radiation passes through a molecule, the bonds stretch or bend by absorbing the radiation. This absorption creates the molecule's absorption spectrum, which is the plot of its percentage transmittance versus wavenumber.
    Transmittance is defined as the ratio of the radiant power passing through a sample to that from the radiation's source. Multiplying the transmittance by 100 gives the percent transmittance (%T), which varies between 100% (no absorption) and 0% (complete...