The magnetic structures of the layer molecular-based ferrimagnets P(C6D5)(4)(MFe)-Fe-II(C2O4)(3) (M-II = Mn, Fe) have been investigated by neutron powder diffraction. The magnetic order in the MnFe compound is best represented by the R3c Shubnikov group with moments aligned along the c axis. In the FeFe compound only one magnetic reflection [201] is observed, indicating incomplete long-range order at 5 K, but with moments also parallel to c.