Ambient pressure chemical vapour deposition of 5,5′-bis((2-(trifluoromethyl)phenyl)ethynyl)-2,2′-bithiophene provides ultrapure needle-shaped crystals. The crystal‘s supramolecular structure consists of an array of hydrogen bonds and π-π interactions leading to anisotropic arrangements. The cyan emitting crystals exhibit an optical waveguiding tendency with guided polarised optical emissions due to anisotropic molecular arrangements. © 2021 Wiley-VCH GmbH