1. Department of Chemistry University of California-Berkeley Berkeley California 94720 U.S.A.
2. Kavli Energy NanoSciences Institute Berkeley California 94720 U.S.A.
3. Dipartimento di Chimica Università degli Studi di Milano Milano 20133 Italy
4. Samara Center for Theoretical Materials Science (SCTMS) Samara State Technical University Samara 443100 Russia