1. Department of Chemistry and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, Department of Theoretical Foundations of Biomedical Sciences and Medical Informatics, Ludwik Rydygier Medical University, ul. Jagiellońska 13, 85-067 Bydgoszcz, Poland, and Institute of Physics, Nicholas Copernicus University, ul. Grudzia̧dzka 5, 87-100 Toruń, Poland