You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 7-chloro-6-[1-(4-fluorophenyl)ethylsulfanyl]-2,3,4,5-tetrahydro-1H-3-benzazepine by IUPAC nomenclature, provide its molecular formula.
user
C18H19ClFNS
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