You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-chloro-5-fluoro-1-(2-fluoroethyl)-2-[5-(imidazol-1-ylmethyl)pyridin-3-yl]benzimidazole is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H14ClF2N5
assistant