K-L and partially exchanged Li-L and Cs-L zeolites were characterised at ambient conditions by performing high-resolution X-ray diffraction measurements. To optimise the resolution, overnight scans (scan speed 0.1°min -1 with step size 0.02° across a 2θ range from 1 to 40°) were performed on a Rigaku Smartlab diffractometer with a high flux rotating copper anode X-ray source (monochromator, λ = 1.544414 Å) at the materials characterisation lab, ISIS Neutron and Muon Source.