US Patent 5,214,173
United States Patent and Trademark Office
University of Iowa Research Foundation (Iowa City, IA, US)
Novel cyclopentadienyl dicarbollide complexes of titanium, zirconiun and hafnium constitute a new class of neutral, 14-electron, d°, mixed-ring, bent-metallocene alkyl complexes which are useful as polymerization catalysts.
Jordan, Richard F. and Crowther, Donna J. Cyclopentadienyl dicarbollide complexes of titanium, zirconium and hafnium. US Patent 5,214,173 filed December 31, 1991 and issued May 25, 1993. https://ir.uiowa.edu/patents/104