The crystal structure of the 'pentamethylcyclopentadienyl cation' is that of the pentamethylcyclopentenyl cation.
The recently reported X-ray crystal structure of the [B(C6F5)4]- salt of the 'pentamethylcyclopentadienyl cation' is actually that of pentamethylcyclopentenyl tetrakis(pentafluorophenyl)borate.
Jones
Jamie N
JN
Department of Chemistry, University of Texas at Austin, Austin, TX 78712, USA.
Cowley
Alan H
AH
Macdonald
Charles L B
CL