Graphene Defects (IMAGE) Penn State Caption This is the simulated collision path of a Krypton-ion (blue) with a defected graphene sheet and subsequent formation of a carbon vacancy (red). Red color shading indicates local strain in the graphene. Credit Kichul Yoon, 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.