A internal mold view showing the pores/tunnels in gaidonnayite, with some of the tunnels shown in cross-section.  The inside of the tunnels/cages are shown as purple, the outside is shown in tan colors.  There are large cages where atoms, like cesium and sodium, can be held; however there are bottlenecked tunnels between these cages (labeled as 7MR), which make it hard for atoms to move around unless hydrogen is there to prop open tunnels and relieve the bottleneck.  Made with OLEX2, \cite{Celestian_2019}.