You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(1H-benzimidazol-2-ylsulfanyl)-1-[4-(1,1,2,2,3,3,3-heptafluoropropylsulfanyl)phenyl]ethanone;hydrobromide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H12BrF7N2OS2
assistant