International first: Gas-phase carbonic acid isolated

Jan 11, 2011
Innsbruck scientists were first in producing two types of carbonic acid crystals. Credit: University of Innsbruck

A team of chemists headed by Thomas Loerting from the University of Innsbruck and Hinrich Grothe from the Vienna University of Technology (TU Wien) in Austria have prepared and isolated gas-phase carbonic acid and have succeeded in characterizing the gas-phase molecules by using infrared spectroscopy. The results were published in the journal Angewandte Chemie International Edition.

In textbooks and other media the widespread belief still prevails that stable carbonic acid cannot be produced in pure form and is practically non-existent as it immediately decomposes to and water. However, Innsbruck chemists headed by Erwin Mayer (Institute of General, Inorganic and ) refuted this persistent dogma in chemistry several years ago. They belong to only a handful of scientists who have prepared pure solid carbonic acid experimentally. In an international first, the scientists have now produced gas-phase carbonic acid and, together with a research group headed by Hinrich Grothe at the Vienna University of Technology, they have also succeeded in proofing the existence of these molecules. "Carbonic acid is composed of at least three different species in the gas-phase: a cyclic dimer consisting of two molecules and two different types of ," explains Thomas Loerting (Institute of ) the result of the comprehensive study.

For this experiment the researchers prepared carbonic acid in the laboratory in Innsbruck. It was then stored in and transported to Vienna by PhD student Jürgen Bernard. At the Institute of Materials Chemistry at the TU Wien the solid carbonic acid was warmed to minus 30 degrees Celsius. "During this process the carbonic acid molecules entered the gas-phase," says Loerting. This is a surprising result because many experts in the field believed that carbonic acid immediately decomposes to carbon dioxide and water. The Austrian scientists trapped the carbonic acid vapor in a solid matrix of the inert gas argon and cooled it down. "This produced a frozen image of the carbonic acid vapor, which we analyzed by using high-resolution at the TU Wien," says Hinrich Grothe. "The spectrum we produced is extremely precise and we were able to assign the spectral bands to the vibration of each single molecule." For more than a decade, the chemists have been supported in their experimental research by Klaus Liedl from the Institute of Theoretical Chemistry in Innsbruck. His team of scientists has helped to interpret the experimental data with computational models. Additional calculations have been performed by Oscar Galvez from CSIC Madrid (Spanish National Research Council).

This experiment not only is of high importance for basic research but also for astronomy. The identification of gas-phase carbonic acid in the atmosphere of celestial bodies may be facilitated by the detailed spectra of gas-phase carbonic acid described in this study. "Conditions in space environments suggest that gas-phase carbonic acid may be found in the coma of comets or the poles of Mars," says Thomas Loerting. "However, infrared spectra currently measured in extraterrestrial environments are still too imprecise to be comparable to the results produced in our laboratory."

Explore further: Researchers create materials that reproduce cephalopods' ability to quickly change colors and textures

Provided by University of Innsbruck

5 /5 (1 vote)
add to favorites email to friend print save as pdf

Related Stories

Climate Is Regulated By Water

Aug 01, 2005

About one hundred years ago, S. Arrhenius brought forward a hypothesis that the atmospheric temperature of at the surface of the Earth was increasing under the influence of the glasshouse effect created by carbonic acid gas. ...

Russian-Style Hunting For Helicobacter Pylori

Oct 21, 2005

Due to the 2005 Nobel Prize in physiology and medicine received by Robin Warren and Barry Marshall, the name of the Helicobacter pylori bacterium is now a buzz word. According to contemporary overview, the bacterium gets ...

Blood Enzyme Could Help Realize Clean Coal

Dec 03, 2009

(PhysOrg.com) -- An enzyme in our blood that enables our lungs to exhale carbon dioxide could be the key to isolating carbon dioxide emissions from coal plants in order to store them safely underground. A ...

Formation of the smallest droplet of acid

Jun 19, 2009

Exactly four water molecules and one hydrogen chloride molecule are necessary to form the smallest droplet of acid. This was the result of work by the groups of Prof. Dr. Martina Havenith (physical chemistry) ...

Recommended for you

Separation of para and ortho water

6 hours ago

(Phys.org) —Not all water is equal—at least not at the molecular level. There are two versions of the water molecule, para and ortho water, in which the spin states of the hydrogen nuclei are different. ...

User comments : 0