Methanol-molecule (IMAGE) Max-Planck-Gesellschaft Caption Schematic image of the methanol molecule. The black sphere represents the central carbon atom, the red one an oxygen atom and the grey spheres represent hydrogen atoms. The yellow arrow represents the internal rotation of the molecule, whose impediment causes a quantum tunnel effect. Credit VU University of Amsterdam / Paul Jansen Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.