Zeolites and zeotype materials are well established in the field of catalytic science. Particularly notable is their use for shape selective, acid-catalyzed conversions of simple hydrocarbons to alcohols, alkenes and aromatics. H-ZSM5 is a well-established catalyst for the commercially important methanol-to-gasoline and methanol-to-olefin processes. For both of these, the first step is to activate methanol by chemisorbing it to the zeolite to generate a chemisorbed methoxy species. The aim of this proposal is to structurally characterise the chemisorbed methoxy group using total scattering neutron diffraction. This will be the first time a reaction intermediate has been structurally characterised inside a zeolite.