1. Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan
2. Molecular Science and Technology, Taiwan International Graduate Program, Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 115, Taiwan
3. Department of Chemistry, National Tsing Hua University, Hsinchu 300, Taiwan
4. Department of Chemistry, Fu Jen Catholic University, New Taipei City 242, Taiwan
5. Department of Physics, National Taiwan University, Taipei 106, Taiwan
6. Nano-Science and Technology Program, Taiwan International Graduate Program, Academia Sinica, Taipei 106, Taiwan
7. Center for Condensed Matter Sciences, National Taiwan University & Center of Atomic Initiative for New Materials, National Taiwan University, Taipei 106, Taiwan