This picture is taken from the birefringent hydrogel with a lamellar structure. This sample is composed of disc-like clay-particles (Laponite) with a positively charged rim, in the presence of the small, barrel-shaped molecule cucurbit[7]uril (CB[7]). More information can be found from our recently published paper: P. Xu, Y. Lan, L. Dai, T. O’Neill, I. Stoev and E. Eiser Discotic ’liquid crystals of cucurbit[7]uril-functionalized Laponite clays’ J. Mol. Phys., accepted (2018).