1. Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-3400, United States
2. Condensed Matter Physics and Materials Science Department, Building 480, Brookhaven National Laboratory, Upton, New York 11973, United States
3. Center for Functional Nanomaterials, Building 735, Brookhaven National Laboratory, Upton, New York 11973, United States
4. Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, New York 11794-3800, United States