title: The halogen-bonded adduct 1,4-bis(pyri-din-4-yl)buta-1,3-diyne-1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexa-deca-fluoro-1,8-diiodo-octane (1/1).
abstract: In the crystal structure of the title compound, C8F16I2·C14H8N2, the mol-ecules form infinite chains parallel to [2-11] through two symmetry-independent C-I⋯N halogen bonds (XBs). As commonly found, the perfluoro-alkyl mol-ecules segregate from the hydro-carbon ones, forming a layered structure. Apart from the XBs, the only contact below the sum of van der Waals radii is a weak H⋯F contact. The topology of the network is a nice example of the paradigm of the expansion of ditopic starting modules; the XB leads to the construction of infinite supramolecular chains along [2-11] formed by alternating XB donors and acceptors.
authors.affiliation: NFMLab, Department of Chemistry, Materials and Chemical Engineering, "G. Natta", Politecnico di Milano, Via Mancinelli, 7, I-20131 Milano, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Cavallo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Marras
authors.forename: Pierangelo
authors.initials: P
authors.lastname: Metrangolo
authors.forename: Tullio
authors.initials: T
authors.lastname: Pilati
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Terraneo