1. Department of Chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters National Tsing Hua University Hsinchu 300044 Taiwan
2. National Synchrotron Radiation Research Center Hsinchu 300092 Taiwan
3. Department of Chemistry National Tsing Hua University Hsinchu 300044 Taiwan
4. Department of Materials Science and Engineering National Yang Ming Chiao Tung University Hsinchu 30010 Taiwan
5. Department of Physics National Changhua University of Education Changhua 50007 Taiwan