ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMonolayers in Three Dimensions: NMR, SAXS, Thermal, and Electron Hopping Studies of Alkanethiol Stabilized Gold ClustersRoger H. Terrill, Timothy A. Postlethwaite, Chun-hsien Chen, Chi-Duen Poon, Andreas Terzis, Aidi James E. Hutchison, Michael R. Clark, George Wignall, Cite this: J. Am. Chem. Soc. 1995, 117, 50, 12537–12548Publication Date (Print):December 1, 1995Publication History Published online1 May 2002Published inissue 1 December...

The structure of self-assembled monolayers thiophenols (I), benzyl mercaptans (II), biphenylthiols (III), and 4-biphenylmethanethiols (IV) on the surface Au(111) are compared using cyclic voltammetry, reflection absorption infrared spectroscopy, scanning tunneling microscopy, ellipsometry contact angle measurement. results suggest that benyzyl form closely packed ordered monolayer, irrespective length a p-alkoxy substituent. For thiophenol biphenylthiol, film lower coverage was formed. A...

Reported here is an efficient recognition of K+ by 15-crown-5 functionalized gold nanoparticles in aqueous matrix containing physiologically important cations, such as Li+, Cs+, NH4+, Mg2+, Ca2+, and excess amount Na+. Upon exposure to K+, the colloidal solution changes from red blue, response surface plasmon absorption dispersed aggregated nanoparticles. The concentration ranges detected this study are 0.099-0.48 mM 7.6 microM-0.14 mM, when concentrations 54.9 7.1 nM, respectively....

We propose a two-step approach to functionalize gold nanoparticles prepared by reducing tetrachloroauric acid trisodium citrate in water. The chloride and physisorbed on the are first displaced thioctic (TA), which is then exchanged thiols containing desired functionality during second step. TA bears carboxylate group disulfide; at high pH, negative charge of former stabilizes disulfide develops two S−Au bonds, retarding desorption kinetics upon further functionalization. slow crucial...

An alternative string theory: The current-versus-potential behavior of metal atom strings (Ni, Co, Cr) is dependent on the strength d-orbital coupling along chain. Penta- and heptachromium each exhibit two sets primary I–V curves, which depend whether CrCr bonds alternate are localized, or delocalized (see picture).

One of the critical issues for realization molecular electronics is development ideal molecule-electrode contacts that render efficient charge transportation and thus attenuate unwanted voltage drop power loss. The conductance at single-molecule level has long been expected to be correlated strongly with electrode materials. However, other than gold, systematic studies a homologous series molecules extract headgroup-metal contact (G(n=0)) have not reported. Carefully examined herein are...

Abstract The study of metal string complexes with 1D transition‐metal frameworks began in the early 1990s. As these provide great insights into metal–metal multiple bonds and may have potential applications as molecular wires, this field research has grown past 20 years. such, electronic structures simplest trinuclear complexes, supporting ligand systems, single‐molecular conductance are discussed. This review introduces development summarizes some important results newly designed...

Electrodes with the functionality of amino acids can be easily prepared by taking advantage strong sulfur−gold interactions and immersing gold electrodes into cysteine solutions. Such exhibit excellent sensitivity selectivity toward copper(II) determination, because bidentate chelation is effective far superior than that any other metal ions. In this study, we demonstrate at a preconcentration time 5 min cysteine-modified electrode has dynamic range 2 orders magnitude (from 5.0 to 0.050...

Local color: Gold nanoparticles (GNPs) bifunctionalized with a crown ether and thioctic acid can be used for the rapid sensing of target analyte naked eye. A color transformation occurs when interparticle hydrogen bonds aggregated GNPs are broken forming dispersion. For example, detection PbII takes only 1 s (see picture).

A record high PCE of up to 3.2% demonstrates that the efficiency hybrid solar cells (HSCs) can be boosted by utilizing a unique mono-aniline end group PSBTBT-NH2 as strong anchor attach CdTe nanocrystal surfaces and simultaneously exploiting benzene–1,3-dithiol solvent–vapor annealing improve charge separation at donor/acceptor interface, which leads efficient transportation in HSCs. Detailed facts importance specialist readers are published "Supporting Information". Such documents...

A switch in time: Gel–sol transitions of a urea-based [2]rotaxane gelator are controlled by the degree solvent exposure hydrogen-bond-donating urea station and orientation hydrogen-bond-accepting CO groups interlocked ethylene glycol based macrocycle (N blue, O red, phenyl green). Both acid/base anion-exchange control can be used to reversibly transition rotaxane 1-pentanol between solution gel states.

Abstract A one‐pot synthesis of large size and high quality AuAg alloy nanoparticles (NPs) with well controlled compositions via hot organic media is demonstrated. Amid the synthesis, complexation between trioctylphosphine (TOP) metal precursors found, which slows down rate nucleation leads to growth large‐size nanoalloys. The wavelength relative intensities resulting plasmon bands are readily fine‐tuned during synthetic process using different Au/Ag molar ratios. In polymer solar cells, a...

Linear metal string complexes of [MnL4(NCS)2] (Scheme 1, M = NiII, CoII, or CrII; n 3 5; L dpa- tpda2- where is dipyridylamido anion and tripyridyldiamido dianion) are studied for the fundamental understanding effect inter-nuclei interactions on electron transfer (ET). The strings isolated within n-alkanethiol monolayers properties ET through various differentiated by scanning tunneling microscopy. Although very similar in physical dimension, their apparent heights against same alkanethiol...

Reported here is a cooperative effect that the sensing efficiency of active group on gold nanoparticles (GNPs) can be significantly influenced by another proximal functional group. We previously developed visual scheme for K+ 15-crown-5-CH2O(CH2)12SH functionalized GNPs in aqueous matrix. Upon adding K+, GNP solution changes from red to blue. Such transform triggered 2-to-1 sandwich complexation crown resulting shift surface plasmon absorption due aggregation. Herein, we discover introducing...

Close to original: A DNA-like double-stranded polymer is synthesized by ring-opening metathesis polymerization of a bisnorbornene derivative containing rigid ferrocene spacer. The forms helices (see picture), supercoils, and ladders, which are observable scanning tunneling microscopy. Supporting information for this article available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2006/z503406_s.pdf or from author. Please note: publisher not responsible content functionality any...

Two new linear pentanickel complexes [Ni5(bna)4(Cl)2][PF6]2 (1) and [Ni5(bna)4(Cl)2][PF6]4 (2; bna=binaphthyridylamide), were synthesized structurally characterized. A derivative of 1, [Ni5(bna)4(NCS)2][NCS]2 (3), was also isolated for the purpose conductance experiments carried out in comparison with [Ni5(tpda)4(NCS)2] (4; tpda=tripyridyldiamide). The metal framework complex 2 is a standard [Ni5]10+ core, isoelectronic that [Ni5(tpda)4Cl2] (5). Also as 5, has an antiferromagnetic ground...

A new class of polymers, which have a double-stranded polybinorbornene skeleton with multilayer planar oligoaryl linkers, defined as polymeric ladderphanes, are synthesized. The structures these ladderphanes determined by spectroscopic means. Photophysical studies and time-resolved fluorescence investigations reveal that there is strong interaction between the chromophore linkers. Thus, Soret band splitting in absorption spectrum polymer porphyrin linker (12e), significant quenching linkers...

The use of single-molecule junctions for various functions constitutes a central goal molecular electronics. functional features and the efficiency electron transport are dictated by degree energy-level alignment (ELA), that is, offset potential between electrode Fermi level frontier orbitals. Examples manifesting ELA rare owing to experimental challenges large energy barriers typical model compounds. In this work, organometallic compounds with five metal centers joined in collinear fashion...

A thiolated bis(cobalt) cofacial diporphyrin chemisorbed on an edge plane pyrolytic graphite electrode has the electrocatalytic activity of a four-electron (n ≥ 3.6) dioxygen reduction catalyst. When gold surface, same catalyst exhibits only two-electron catalyst, producing hydrogen peroxide = 2.1). The surface thus plays crucial, but not understood, role in designed catalysis. Analysis X-ray photoelectron spectroscopy and UV−vis results is consistent with rings porphyrins being coplanar to...

In undergoing a DNA-like replication process, the single-stranded polynorbornene acts as template for norbornene monomer adhesion through ester linkages (see scheme). Polymerization of adhered monomers affords corresponding unsymmetric double-stranded polymer, which produces complementary carboxylic acid after hydrolysis. The overall process involves pass information from polymer to daughter polymer.

EMACs (extended metal-atom chains) offer a unique platform for the exploration of metal-metal interactions. There has been significant advances on synthesis EMACs, such as lengthening chains up to 11 metal atoms thus far, integrating naphthyridine moieties tuning charge carried at centers, and manipulation However, centers in hitherto are limited first row transition metals which more labile than those relatively inert ones with electrons filled 4d 5d shells. In this Communication,...

Abstract One‐dimensional nanostructures containing heterojunctions by conjugated polymers, such as nanowires, are expected to greatly facilitate efficient charge transfer in bulk‐heterojunction (BHJ) solar cells. Thus, a combined theoretical and experimental approach is pursued explore spontaneous nanowire formation. A dissipative particle dynamics simulation first performed study the morphologies formed rodlike polymers with various side‐chain structures. The results surprisingly predict...