1. The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
2. Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States and Department of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
3. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
4. The Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
5. Department of Physics, Tsinghua University, Beijing 100084, China