1. Department
of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
2. Department of Chemistry, James Frank Institute, and The Institute for Biophysical Dynamics, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
3. Cherry L. Emerson Center for Scientific Computation, Department of Chemistry, Emory University, 1515
Dickey Drive, Atlanta, Georgia 30322, United States