1. Department
of Chemistry, Southern Methodist University, 3215 Daniel Avenue, Dallas, Texas 75275-0314, United States
2. Laboratory
of Computational Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
3. Q-Chem Inc., 6601 Owens Drive,
Suite 105, Pleasanton, California 94588, United States