You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2',5'-bis(9-phenylcarbazol-3-yl)spiro[fluorene-9,7'-indeno[2,1-b]carbazole];7,7-dimethyl-2,5-bis(9-phenylcarbazol-3-yl)indeno[2,1-b]carbazole into its molecular formula.
user
C124H80N6
assistant