We report the growth of MgO[001]//Fe(6 nm)/MgO(7 nm) and MgO[001]//Fe(6 nm)/Pt(6 nm) by molecular beam epitaxy and show that the full characterization by spin-orbit ferromagnetic resonance (SO-FMR) allows the determination of magnetic anisotropies by classical FMR-only studies. The spin mixing conductance of the epitaxial Fe/Pt interface was measured to be g e ffect ? ? = 2.6 ± 0.5 × 10 19 m 2 , and the effective spin Hall angle (SHA) θ SHE e ffect was estimated at different in-plane crystalline directions. It was found that θ SHE e ffect is the same in all directions. When taking into account high enough excitation frequencies to achieve uniform precession of magnetization, the effective SHA for epitaxial Pt in Fe/Pt is θ SHE e ffect = 0.051 ± 0.005. We address about the proper conditions to determine those relevant spintronic parameters.