1. Department of Chemistry, Bioscience and Environmental Engineering, Faculty of Science and Technology, University of Stavanger, N-4036 Stavanger, Norway
2. Beijing International Center for Gas Hydrate & College of Engineering, Peking University, Beijing 100871, China
3. Johannes Gutenberg-Universität Mainz, Department of Chemistry, Duesbergweg 10−14, 55128 Mainz, Germany