`CIF_(3)` exists but `FCl_(3)` does not-why?

Explanation

Cl has vacant d -orbitals in its valence shell. Therefore, it can exhibit an oxidation state of +3 by expanding its octet. In the first excited state, Cl contains three unpaired electrons which forms three covalent bonds with three F -atoms giving `CIF_(3)` . On the other hand, F has no vacant d -orbitals. So it cannot exhibit any higher oxidation state.