1. Contribution from the School of Chemistry and Biochemistry and Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA; Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA; Department of Natural Sciences, New Mexico Highlands University, Las Vegas, New Mexico 87701, USA; Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia