Molecular Structure (IMAGE) Penn State Caption Each diffusion path for an oxygen atom (red) moving across a graphene ring composed of carbon atoms (gray ) is considered a 'distortion' and is indexed by a unique 'distortion symmetry group' indicated below each image. The symmetry group contains all the essential information about the properties of the material system as the diffusion occurs, including the ability to help determine the minimum energy pathway. In this case, the minimum energy pathway is when oxygen moves around the ring (right image) rather than across it (left image). Credit Venkat Gopalan, Penn State Usage Restrictions non commercial use only 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.