title: Self-assembly of decoupled borazines on metal surfaces: the role of the peripheral groups.
abstract: Two borazine derivatives have been synthesised to investigate their self-assembly behaviour on Au(111) and Cu(111) surfaces by scanning tunnelling microscopy (STM) and theoretical simulations. Both borazines form extended 2D networks upon adsorption on both substrates at room temperature. Whereas the more compact triphenyl borazine 1 arranges into close-packed ordered molecular islands with an extremely low density of defects on both substrates, the tris(phenyl-4-phenylethynyl) derivative 2 assembles into porous molecular networks due to its longer lateral substituents. For both species, the steric hindrance between the phenyl and mesityl substituents results in an effective decoupling of the central borazine core from the surface. For borazine 1, this is enough to weaken the molecule-substrate interaction, so that the assemblies are only driven by attractive van der Waals intermolecular forces. For the longer and more flexible borazine 2, a stronger molecule-substrate interaction becomes possible through its peripheral substituents on the more reactive copper surface.
authors: Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL (UK).
authors: Nataliya
authors: N
authors: Kalashnyk
authors: Praveen
authors: P
authors: Ganesh Nagaswaran
authors: Simon
authors: S
authors: Kervyn
authors: Massimo
authors: M
authors: Riello
authors: Ben
authors: B
authors: Moreton
authors: Tim S
authors: TS
authors: Jones
authors: Alessandro
authors: A
authors: De Vita
authors: Davide
authors: D
authors: Bonifazi
authors: Giovanni
authors: G
authors: Costantini
mesh_terms: D001896:Boron Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D008958:Models, Molecular; D012834:Silver / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D001896:Boron Compounds; D012834:Silver; D003300:Copper; C522695:borazine
keywords: borazines; molecular dynamics; scanning tunnelling microscopy; self-assembly; surface chemistry