  The intermetallic compound \PFA\ that possesses a three-dimensional network
structure of Al polyhedra centered at the transition metal element Fe and the
rare earth Pr is investigated through neutron powder diffraction and inelastic
neutron scattering in order to elucidate the magnetic ground state of Pr and Fe
and the crystal field effects of Pr. Our neutron diffraction study confirms
long-range magnetic order of Pr below $T_N $ = 4.5~K in this compound.
Subsequent magnetic structure estimation reveals a magnetic propagation vector
$k$ = ($\frac{1}{2}$~0~$\frac{1}{2}$) with a magnetic moment value of
2.5~$\mu_\mathrm{B}$/Pr along the orthorhombic $c$-axis and evidence the lack
of ordering in the Fe sublattice. The inelastic neutron scattering study
reveals one crystalline electric field excitation near 19~meV at 5~K in \PFA.
The energy-integrated intensity of the 19~meV excitation as a function of |$Q$|
$(A^{-1})$ follows the square of the magnetic form factor of Pr$^{3+}$ thereby
confirming that the inelastic excitation belongs to the Pr sublattice. The
second sum rule applied to the dynamic structure factor indicates only
1.6(2)~$\mu_\mathrm{B}$ evolving at the 19~meV peak compared to the
3.58~$\mu_\mathrm{B}$ for free Pr$^{3+}$, indicating that the crystal field
ground state is magnetic and the missing moment is associated with the
resolution limited quasi-elastic line. The magnetic order occurring in Pr in
\PFA\ is counter-intuitive to the symmetry-allowed crystal field level scheme,
hence, is suggestive of exchange-mediated mechanisms of ordering stemming from
the magnetic ground state of the crystal field levels.
