Improved Infrared Spectroscopic Method for the Measurement of 13C: 12C Ratios
- 1 January 1997
- journal article
- Published by SAGE Publications in Applied Spectroscopy
- Vol. 51 (1) , 17-21
- https://doi.org/10.1366/0003702971938911
Abstract
Pressure broadening of an infrared absorption band of gaseous CO2 makes measurement of a band intensity very much easier and also much more precise in comparison with the results obtained by measuring the intensity of a single line in a gas-phase spectrum. The isotopic shift of the v3 bands for carbon dioxide centered at 2350 cm−1 is sufficient to completely separate the P branch for 13CO2 from the two branches for 12CO2. The intensity ratios can be measured accurately on a low-resolution FT-IR spectrometer when the CO2 is pressurized to 10 bar (106N m−2) with N2, permitting isotope ratio differences as small as 0.02 atom % above the natural abundance of 1.11 atom % to be detected.Keywords
This publication has 14 references indexed in Scilit:
- The applicability of evacuated serological tubes for the collection of breath for isotopic analysis of CO2 by isotope ratio mass spectrometryJournal of Mass Spectrometry, 1988
- Measurement of carbon-13 dioxide/carbon-12 dioxide abundance by nondispersive infrared heterodyne ratiometry as an alternative to gas isotope ratio mass spectrometryAnalytical Chemistry, 1986
- High resolution infrared diode laser spectroscopy for isotope analysis—Measurement of isotopic carbon monoxideApplied Physics Letters, 1986
- Comparison of infrared and mass-spectrometric measurements of carbon-13/carbon-12 ratiosThe International Journal of Applied Radiation and Isotopes, 1985
- Infrared Spectrophotometric Determination of 13C EnrichmentApplied Spectroscopy, 1984
- Determination of13C in plant materials by infrared absorption spectrometry using a simple calibration methodSoil Science and Plant Nutrition, 1983
- Optical Analysis of 12C/13C and 12C/14C Ratios in Carbon Dioxide, by Measurements on the CO+ Spectrum in the Wavelength Interval between 210 and 250 nmApplied Spectroscopy, 1980
- Determination of carbon-13 by infrared spectrophotometry of carbon monoxideAnalytical Chemistry, 1970
- The infrared isotope analyzer IIPhysica, 1954
- Determination of Isotope Ratios, e.g., in Tracer Work, by an Infrared Absorption MethodThe Journal of Chemical Physics, 1951