1. Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
2. State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China
3. Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
4. National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
5. Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
6. Department of Physics, Florida A&M University, Tallahassee, Florida 32307, United States