1. Department of Materials Science and Engineering and California NanoSystems Institute, University of California Los Angeles, Los Angeles, CA 90095, USA.
2. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
3. Department of Chemistry, University of California, Los Angeles, CA 90095, USA.
4. Department of Physics, Marmara University, 34722 Ziverbey, Istanbul, Turkey.
5. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
6. Center for Materials Research, Washington State University, Pullman, WA 99164, USA.
7. Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.