Related Experiment Video
Updated: Jun 16, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Quantitative liquid-phase infrared spectra of several simple organic compounds
Abstract:
Many simple compounds exhibit pronounced changes in absorptivity between the vapor and liquid phases, particularly at longer wavelengths in the infrared. Therefore liquid-phase spectral data cannot be computed from available quantitative vapor spectra. Quantitative liquid spectra are presented for methanol, ethanol, formic acid, acetic acid, acetone, and diethyl ether in the region 2.5-13 microm. While phase-transition changes in absorptivity of these compounds do not approach those of water, they can be significant, and troublesome if not appreciated.
Related Concept Videos
Infrared (IR) Spectroscopy: Overview
Different compounds display unique properties due to their...
IR Spectrum
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...
IR Spectroscopy: Molecular Vibration Overview
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
IR Frequency Region: Fingerprint Region
The...
Spectroscopy of Carboxylic Acid Derivatives
In the...
IR and UV–Vis Spectroscopy of Aldehydes and Ketones

