<title>Conducting molecular nanostructures assembled from charge-transfer complexes grafted onto silicon surfaces</title>

Abstract

Heterodimeric electon-donor/electron-acceptor charge-transfer complexes chemisorbed onto Au(111) by attachment of the electron-donor to the surface have been characterized by scanning tunneling microscopy and Kelvin probe experiments. Conductance measurements exhibit nearly Ohmic I(V) responses at low bias. The electrical properties of the charge-transfer complex are vastly different than those of the electron-donor alone which exhibits insulating behavior at low bias. In an extension of this work, strategies are being developed for attachment of chargetransfer complexes to semiconducting or insulating surfaces. Fabrication of nanoscale molecular electronic devices is being investigated by attaching one component of a charge-transfer complex to a silicon surface by chemically directed self-assembly. The single component-functionalized surface is then used as a substrate on which the second component of the charge-transfer complex is deposited by the atomic force microscopy method, dip-pen nanolithography (DPN). Derivatives of hexamethylbenze (electron-donor) with terminal olefins attached to crystalline silicon surfaces via hydrosilylation form monolayer-functionalized silicon surfaces that are expected to have insulating properties. Welldefined features can be "drawn" onto the donor-functionalized surfaces by DPN using tetracyanoethylene (electronacceptor) as the "ink." The resulting charge-transfer complex nanostructures have conducting properties suitable for device function and are flanked by an insulating monolayer, thus creating "wires" made from charge-transfer complexes.

Synthesis and styrene copolymerization of novel ring-substituted isobutyl phenylcyanoacrylates

“…3-Ethenyl-1,2,4,5-tetramethylbenzene is reported in synthesis of cyclopropyl ring by action of sodium amide on exo-methyleneammonium ions obtained from rearrangement of certain 2,6-dimethylbenzyltrimethylammonium ions [25], and in studies of thermal reactivity of polynuclear aromatic hydrocarbons [26]. 3,4,5,pentamethylbenzene was active in Manganese-catalysed divergent silylation of alkenes [27], in photoredox divergent 1,2-difunctionalization of alkenes with gem-dibromides [28], in mechanistic studies on Platinum(II) catalyzed hydroarylation of alkynes [29], in studies of conductivity molecular nanostructures assembled from charge-transfer complexes grafted onto silicon surfaces [30], in polymerization yielding poly(pentamethylstyrene) [31].…”