1. Center for Computational Molecular Science and Technology, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30318, USA
2. Molecular Structure and Design, Bristol Myers Squibb Company, P.O. Box 5400, Princeton, New Jersey 08543, USA
3. Center for Computational Molecular Science and Technology, School of Chemistry and Biochemistry and School of Computational Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30318, USA