This proposal aims to study condensation transitions in nanoporous flexible materials by means of wide Q-range neutron diffraction. We plan to perform an in-situ gas adsorption/desorption experiment on the zeolitic imidazole framework ZIF-8 and monitor the behaviour of the adsorbate upon condensation within the pores during the “gate opening” structural transition. This neutron study complements our X-ray absorption and X-ray emission spectroscopy work performed at the I20 beamline at Diamond. With this combined study we expect to provide improved understanding of the microscopic details of the host-guest interactions for ZIF materials that will be very valuable for a molecular understanding of the framework flexibility and the “gate opening” phenomena.