Chemists have discovered that an ‘impossible’ reaction at cold temperatures actually occurs with vigour, which could change our understanding of how alcohols are formed and destroyed in space.
To explain the impossible, the researchers propose that a quantum mechanical phenomenon, known as ‘quantum tunnelling’, is revving up the chemical reaction. They found that the rate at which the reaction occurs is 50 times greater at minus 210 degrees Celsius than at room temperature.
It’s the harsh environment that makes space-based chemistry so difficult to understand; the extremely cold conditions should put a stop to chemical reactions, as there isn’t sufficient energy to rearrange chemical bonds. It has previously been suggested that dust grains—found in interstellar clouds, for example—could lend a hand in bringing chemical reactions about.
The idea is that the dust grains act as a staging post for the reactions to occur, with the ingredients of complex molecules clinging to the solid surface. However, last year, a highly reactive molecule called the ‘methoxy radical’ was detected in space and its formation couldn’t be explained in this way.
Laboratory experiments showed that when an icy mixture containing methanol was blasted with radiation—like would occur in space, with intense radiation from nearby stars, for example –methoxy radicals weren’t released in the emitted gases. The findings suggested that methanol gas was involved in the production of the methoxy radicals found in space, rather than any process on the surface of dust grains. But this brings us back to the problem of how the gases can react under extremely cold conditions.
Read more at: Phys.org