Chloro compound of vanadium has only spin magnetic moment of 1.73 BM. This vanadium chloride has the formula:

The spin magnetic moment is given as,

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

$$\begin{gathered} 1.73=\sqrt{n(n+2)} \\ \sqrt{3}=\sqrt{n(n+2)} \end{gathered}$$

$n=1$

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

$V(23)=[Ar]3d^{3}4s^2$
$V^{4+}=[Ar]3d^{1}4s^0$

Therefore, the chloride has the formula $VC{l}_4$.