The crystal structures and magnetic ordering of layered compounds that have been modified by low temperature chemical methods will be probed using neutrons. The systems Sr2MnO2Cu1.5-zS2 are obtained by the removal of some of the copper from Sr2MnO2Cu1.5S2 using an iodine solution. This process is topotactic and conserves the basic structure, but the details of the crystal structure are sensitive to the concentration of copper ion vacancies and the magnetic behaviour is sensitive to the oxidation of manganese which occurs in these reactions. Variable temperature neutron diffraction is a key probe of the magnetic order and the structural behaviour and will give insight into the fundamental magnetic, electronic and transport properties of these materials.