Calix[4]arenes at the upper rim substituted with two (thio)urea moieties, 2a-c and 4, or substituted with two acetamido groups, 5, adopt a pinched cone conformation in CDCl 3 solution. The pinched cone conformation is the result of diametrical, intramolecular hydrogen bonds and was studied by 1 H NMR dilution and variable-temperature experiments, NOESY spectroscopy, and FTIR experiments. The pinched cone conformation in these novel calix[4]arenes is stable in C 2 D 2 Cl 4 up to at least 120°C. The bis(ureido)calix[4]arenes 2b,c give a hydrogen-bonded dimer in the pinched cone conformation.

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High quality opal‐like photonic crystals containing graphene are fabricated using evaporation‐driven self‐assembly of soft polymer colloids. A miniscule amount of pristine graphene within a colloidal crystal lattice results in the formation of colloidal crystals with a strong angle‐dependent structural color and a stop band that can be reversibly shifted across the visible spectrum. The crystals can be mechanically deformed or can reversibly change color as a function of their temperature, hence their sensitive mechanochromic and thermochromic response make them attractive candidates for a wide range of visual sensing applications. In particular, it is shown that the crystals are excellent candidates for visual strain sensors or integrated time‐temperature indicators which act over large temperature windows. Given the versatility of these crystals, this method represents a simple, inexpensive, and scalable approach to produce multifunctional graphene infused synthetic opals and opens up exciting applications for novel solution‐processable nanomaterial based photonics.