1. Department of Chemistry, Princeton University, Princeton, NJ, USA
2. Program in Applied and Computational Mathematics, Princeton University, Princeton, NJ, USA
3. Department of Physics, Temple University, Philadelphia, PA, USA
4. Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing, People's Republic of China
5. Department of Mathematics, Princeton University, Princeton, NJ, USA
6. Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
7. Department of Physics and Princeton Institute for the Science and Technology of Materials, Princeton University, Princeton, NJ, USA