The Helical Structure of Diallylamine in the Solid State

Abstract

In the solid state diallylamine forms supramolecular helices with four molecules per pitch that are held together by hydrogen bonding. The helical structure is the result of competing length scales at which hydrogen bonding and second-neighbour Van-der-Waals interactions occur. The structure features two crystallographically independent helices and four unique molecules in the asymmetric unit (Z′ = 4). The high Z′ value is partly a consequence of the centrosymmetric pseudo-hexagonal packing of helical columns, which is incompatible with helical spacegroup symmetries.Graphic