Recent reports have shown that magnetic materials exhibiting record large coercivities can be obtained by introducing weak magnetic interactions between strongly anisotropic one-dimensional, magnetic chains. This physical behaviour is however largely unexplained. Furthermore, the chains themselves are interesting as a metastable magnetization remains in the paramagnetic phase and persists, surprisingly, in the antiferromagnetically ordered phase. We have obtained several examples of magnetic chains by polymerizing the strongly anisotropic [Mn(III)-Re(IV)-Mn(III)] magnetic motif. Herein, the S = 5/2 units are coupled by weak ferromagnetic interactions along the chain and weak antiferromagnetic interactions between adjacent chains. We propose to employ neutron powder diffraction to determine the magnetic ground state (para- or antiferro-magnetic) and in addition determine the magnetic structure. Studies of a small family of chains with varying inter-chain separations (and therefore varying Néel temperatures) facilitate a magneto-structural correlation for this kind of molecular magnetic materials.