A series of heavier group 14 element, terminal phosphide complexes, M(BDI)(PR2) (M = Ge, Sn, Pb; BDI = CH{(CH3)CN-2,6-iPr(2)C(6)H(3)}(2); R = Ph, Cy, SiMe3) have been synthesized. Two different conformations (endo and exo) are observed in the solid-state; the complexes with an endo conformation have a planar coordination geometry at phosphorus (M = Ge, Sn; R = SiMe3) whereas the complexes possessing an exo conformation have a pyramidal geometry at phosphorus. Solution-state NMR studies reveal through space scalar coupling between the tin and the isopropyl groups on the N-aryl moiety of the BDI ligand, with endo and exo exhibiting different J(SnC) values. The magnitudes of the tin-phosphorus and lead-phosphorus coupling constants, vertical bar J(SnP)vertical bar and vertical bar J(PbP)vertical bar, differ significantly depending upon the hybridization of the phosphorus atom. For Sn(BDI)(P{SiMe3}(2)), vertical bar J(SnP)vertical bar is the largest reported in the literature, surpassing values attributed to compounds with tin-phosphorus multiple-bonds. Low temperature NMR studies of Pb(BDI)(P{SiMe3}(2)) show two species with vastly different vertical bar J(PbP)vertical bar values, interpreted as belonging to the endo and exo conformations, with sp(2)- and sp(3)-hybridized phosphorus, respectively.