18-Jan-2011 - Universität Innsbruck

International First: Gas-phase Carbonic Acid Isolated

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 carbon dioxide and water. However, Innsbruck chemists headed by Erwin Mayer (Institute of General, Inorganic and Theoretical Chemistry) 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 vapor is composed of at least three different species in the gas-phase: a cyclic dimer consisting of two molecules and two different types of monomers,“ explains Thomas Loerting (Institute of Physical Chemistry) the result of the comprehensive study.

Surprising result

For this experiment the researchers prepared carbonic acid in the laboratory in Innsbruck. It was then stored in liquid nitrogen 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 infrared spectroscopy 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).

Infrared spectra in research

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.“

More about Universität Innsbruck
  • News

    Researchers find a way to check that quantum computers return accurate answers

    Quantum computers become ever more powerful, but how can we be sure that the answers they return are accurate? A team of physicists from Vienna, Innsbruck, Oxford, and Singapore solves this problem by letting quantum computers check each other. Quantum computers are advancing at a rapid pac ... more

    Supersolid in a new dimension

    Quantum matter can be solid and fluid at the same time – a situation known as supersolidity. Researchers led by Francesca Ferlaino have now created for the first time this fascinating property along two dimensions. They now report in the journal Nature on the realization of supersolidity al ... more

    Scrambled supersolids

    Supersolids are fluid and solid at the same time. Physicists from Innsbruck and Geneva have for the first time investigated what happens when such a state is brought out of balance. They discovered a soft form of a solid of high interest for science. As the researchers led by Francesca Ferl ... more

More about TU Wien
  • News

    A Sandblaster at the Atomic Level

    From semiconductors to moon rocks: Many materials are treated with ion beams. A research group at TU Wien has now been able to explain how this process depends on the roughness of the surface. If you want to remove a layer of paint from a metal surface, you can use a sandblaster: Countless ... more

    Anchoring single atoms

    There is a dictum to “never change a running system”. New methods can however be far superior to older ones. While to date chemical reactions are mainly accelerated by catalytic materials that comprise several hundreds of atoms, the use of single atoms could provide a new approach for catal ... more

    How ions get their electrons back

    Very unusual atomic states are produced at TU Wien: Ions are created by removing not just one but 20 to 40 electrons from each atom. These “highly charged ions” play an important role in current research. For a long time, people have been investigating what happens when such highly charged ... more

  • Videos

    Epoxy Resin

    A flash of ultraviolet light sets off a chain reaction which hardens the whole object. more

    Noreia

    The coating machine Noreia was built at TU Wien. This time-lapse video shows the construction process. more

    Shaping Drops: Control over Stiction and Wetting

    Some surfaces are wetted by water, others are water-repellent. TU Wien (Vienna), KU Leuven and the University of Zürich have discovered a robust surface whose adhesive and wetting properties can be switched using electricity. This remarkable result is featured on the cover of Nature magazin ... more