1. Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
2. Department of Chemistry, University of California, Berkeley, California 94720, USA; Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; and The Sackler Center for Computational Molecular and Materials Science, Tel Aviv University, Tel Aviv 69978, Israel
3. Department of Physics, Nagoya University, Nagoya 464-8602, Japan