Hexagonal cluster formation (IMAGE) University of Oxford Caption The study found that negatively charged silica microparticles suspended in water attracted each other to form hexagonally arranged clusters. Image credit: Cover image: Zhang Kang. Credit Cover image: Zhang Kang. Usage Restrictions The image can be used for editorial purposes only if credited. It CANNOT be distributed to third parties. License Original 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.