\(\mu =\sqrt{n(n+2)} \)

\(1.73 =\sqrt{n(n+2)} \)

\(n =1\)

The configuration of vanadium when number of unpaired electron is \(1\) is given as,

\(V (23) =[ Ar ] 3 d^{3} 4 s^{2} \)

\(V ^{4+} =[ Ar ] 3 d^{1} 4 s^{0}\)

Therefore, the chloride has the formula \(VCl _{4}\)