1. Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
2. Centre for Molecular Simulation and Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
3. Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
4. Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
5. Centre for Molecular Simulation and Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada