Hepta- and Octacoordinate Boron in Molecular Wheels of Eight- and Nine-Atom Boron Clusters: Observation and Confirmation

Hua-Jin Zhai, Anastassia N. Alexandrova, K. Alexander Birch, Alexander I. Boldyrev, Lai-Sheng Wang
Angewandte Chemie International Edition
Volume 42, Issue 48, 2003. Pages 6004-6008