Related Experiment Video
Updated: Aug 17, 2026

Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
FTIR Spectrum of the nu4 Band of DCOOD
1Faculty of Science, National University of Singapore, Lower Kent Ridge Road, 119260, Singaporee
Abstract:
The FTIR spectrum of the nu4 band of deuterated formic acid (DCOOD) has been measured with a resolution of 0.004 cm-1 in the frequency range of 1120 to 1220 cm-1. A total of 1866 assigned transitions have been analyzed and fitted using a Watson's A-reduced Hamiltonian in the Ir representation to derive rovibrational constants for the upper state (v4 = 1) with a standard deviation of 0.00036 cm-1. In the course of the analysis, the constants for the ground state were improved by a simultaneous fit of microwave frequencies and combination differences from the infrared measurements. Due to the relatively unperturbed nature of the band, the constants can be used to accurately calculate the infrared line positions for the whole band. Although the band is a hybrid type A and B, only a-type transitions were strong enough to be observed. The band center is at 1170.79980 +/- 0.00002 cm-1. Copyright 1999 Academic Press.
More Related Videos
Related Concept Videos
IR Spectrum Peak Broadening: Hydrogen Bonding
However, the extent of hydrogen bonding influences the observed stretching frequency and band broadening. Intermolecular or intramolecular hydrogen bonding...
IR and UV–Vis Spectroscopy of Carboxylic Acids
However, the stretching absorptions for the C=O bond vary depending on the structure of carboxylic acids. The C=O bond of the free carboxylic acids shows a higher stretching frequency, 1760 cm−1, while H-bonded carboxylic acids (dimers) exhibit stretching absorptions at a lower frequency, 1710 cm−1. The C=O bond of the...
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 Absorption Frequency: Delocalization
In IR spectroscopy,...
IR Frequency Region: X–H Stretching
IR Frequency Region: Fingerprint Region
The...

