Channel forming organic crystals: guest alignment and properties

Purely organic solid state materials providing nanometre sized parallel channels are suited for physical property design. In this tutorial review, key materials in this field are reviewed along with new directions forming porous covalent and polymeric networks. Among many known host materials, perhydrotriphenylene (PHTP), tris-(o-phenylenedioxy)-cyclotriphosphazene (TPP) and members of the 2,4,6-tris-(4-halo-phenoxy)-1,3,5 triazine (4-X-POT) family are prime materials for hosting guest molecules featuring diverse physical functionality.