You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 12,12-dimethyl-8-aza-11-azoniapentacyclo[9.7.2.02,7.08,20.015,19]icosa-1(18),2,4,6,9,11(20),15(19),16-octaene ?
user
C20H19N2+
assistant