Abstract: | The peptide di‐l ‐phenylalanine (FF) has emerged as a highly potent candidate for the development of novel nanomaterials. The unprotected peptide was dissolved in 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP) mixed with tetrahydrofuran (THF) and single crystals of the THF monosolvate, C18H20N2O3·C4H8O, were grown by slow evaporation in a `vial‐in‐closed‐bottle' system. THF is a molecule that can only act as a hydrogen‐bond acceptor. Thus, the hydrogen‐bond patterns observed in the crystal structures at 100 and 299 K are different compared to that of crystals grown from water and methanol [Mason et al. (2014). ACS Nano. 8 , 1243–1253]. |