Molecular Knots (IMAGE) Université de Genève Caption Chemical structure of one of the molecular knots under study. Below, it is shown with a simplified representation that the same knot can be tight or loose. In the molecular world, the tight knots have different properties from the loose knots. Credit © UNIGE 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.