Which of following will have the most negative electron gain enthalpy and which the least negative? F, P, S, Cl

$\mathrm{Cl}\to \left[\mathrm{Ne}\right]3{\mathrm{s}}^{2}3{\mathrm{p}}^5$

$\mathrm{P}\to \left[\mathrm{Ne}\right]3{\mathrm{s}}^{2}3{\mathrm{p}}^3⟶\text{ stable half-filled configuration }$

$\text{ Most negative electron gain enthalpy }\to \mathrm{Cl}$

$\text{ Least negative electron gain enthalpy }\to \mathrm{P}$