Charge transport in molecular electronic junctions: compression of the molecular tunnel barrier in the strong coupling regime.

Abstract:

:Molecular junctions are essentially modified electrodes familiar to electrochemists where the electrolyte is replaced by a conducting "contact." It is generally hypothesized that changing molecular structure will alter system energy levels leading to a change in the transport barrier. Here, we show the conductance of seven different aromatic molecules covalently bonded to carbon implies a modest range (< 0.5 eV) in the observed transport barrier despite widely different free molecule HOMO energies (> 2 eV range). These results are explained by considering the effect of bonding the molecule to the substrate. Upon bonding, electronic inductive effects modulate the energy levels of the system resulting in compression of the tunneling barrier. Modification of the molecule with donating or withdrawing groups modulate the molecular orbital energies and the contact energy level resulting in a leveling effect that compresses the tunneling barrier into a range much smaller than expected. Whereas the value of the tunneling barrier can be varied by using a different class of molecules (alkanes), using only aromatic structures results in a similar equilibrium value for the tunnel barrier for different structures resulting from partial charge transfer between the molecular layer and the substrate. Thus, the system does not obey the Schottky-Mott limit, and the interaction between the molecular layer and the substrate acts to influence the energy level alignment. These results indicate that the entire system must be considered to determine the impact of a variety of electronic factors that act to determine the tunnel barrier.

authors

Sayed SY,Fereiro JA,Yan H,McCreery RL,Bergren AJ

doi

10.1073/pnas.1201557109

subject

Has Abstract

pub_date

2012-07-17 00:00:00

pages

11498-503

issue

29

eissn

0027-8424

issn

1091-6490

pii

1201557109

journal_volume

109

pub_type

杂志文章
  • Photochemical dimerization of parinaric acid in lipid bilayers.

    abstract::Parinaric acid (9,11,13,15-octadecatetraenoic acid), a conjugated tetraene fatty acid, undergoes a second-order photochemical reaction in phospholipid bilayers. The reaction results in the loss of the characteristic absorption of this chromophore and the development of new absorption demonstrating the presence of a tr...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.77.1.26

    authors: Morgan CG,Hudson B,Wolber PK

    更新日期:1980-01-01 00:00:00

  • RNA synthesis in isolated brian nuclei after administration of d-lysergic acid diethylamide (LSD) in vivo.

    abstract::RNA synthesis in isolated brain nuclei was analyzed 2.5 hr after the intravenous administration of d-lysergic acid diethylamide (LSD) to young rabbits. The drug stimulated transcription by 54% in brain stem nuclei and by 13% in cerebral hemisphere nuclei expressed over saline controls. Both nucleoplasmic and nucleolar...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.72.3.837

    authors: Brown IR

    更新日期:1975-03-01 00:00:00

  • Isolation and characterization of DNA sequences amplified in multidrug-resistant hamster cells.

    abstract::The mechanism by which mammalian cells acquire resistance to chemotherapeutic agents has been investigated by using molecular genetic techniques. LZ and C5, two independently derived multidrug-resistant Chinese hamster cell lines, share specific amplified DNA sequences. We demonstrate that commonly amplified DNA seque...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.83.2.337

    authors: Gros P,Croop J,Roninson I,Varshavsky A,Housman DE

    更新日期:1986-01-01 00:00:00

  • Fibulin-4 exerts a dual role in LTBP-4L-mediated matrix assembly and function.

    abstract::Elastogenesis is a hierarchical process by which cells form functional elastic fibers, providing elasticity and the ability to regulate growth factor bioavailability in tissues, including blood vessels, lung, and skin. This process requires accessory proteins, including fibulin-4 and -5, and latent TGF binding protein...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.1901048116

    authors: Kumra H,Nelea V,Hakami H,Pagliuzza A,Djokic J,Xu J,Yanagisawa H,Reinhardt DP

    更新日期:2019-10-08 00:00:00

  • Quality-control mechanisms targeting translationally stalled and C-terminally extended poly(GR) associated with ALS/FTD.

    abstract::Maintaining the fidelity of nascent peptide chain (NP) synthesis is essential for proteome integrity and cellular health. Ribosome-associated quality control (RQC) serves to resolve stalled translation, during which untemplated Ala/Thr residues are added C terminally to stalled peptide, as shown during C-terminal Ala ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.2005506117

    authors: Li S,Wu Z,Tantray I,Li Y,Chen S,Dong J,Glynn S,Vogel H,Snyder M,Lu B

    更新日期:2020-10-06 00:00:00

  • Crystal structure of human aquaporin 4 at 1.8 A and its mechanism of conductance.

    abstract::Aquaporin (AQP) 4 is the predominant water channel in the mammalian brain, abundantly expressed in the blood-brain and brain-cerebrospinal fluid interfaces of glial cells. Its function in cerebral water balance has implications in neuropathological disorders, including brain edema, stroke, and head injuries. The 1.8-A...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0902725106

    authors: Ho JD,Yeh R,Sandstrom A,Chorny I,Harries WE,Robbins RA,Miercke LJ,Stroud RM

    更新日期:2009-05-05 00:00:00

  • Pathogenic polyglutamine proteins cause dendrite defects associated with specific actin cytoskeletal alterations in Drosophila.

    abstract::Whereas the neurodegeneration associated with various polyglutamine (polyQ) diseases has prompted extensive studies of polyQ-induced cell death, the neuronal loss that typically appears during late stages of the diseases may not account for the preceding movement and mental disorders. The cellular basis for polyQ-indu...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.1113573108

    authors: Lee SB,Bagley JA,Lee HY,Jan LY,Jan YN

    更新日期:2011-10-04 00:00:00

  • HLA class II allelic variation and susceptibility to pemphigus vulgaris.

    abstract::The autoimmune dermatologic disease pemphigus vulgaris (PV) is associated with the HLA serotypes DR4 and DRw6. Susceptibility to PV could be conferred either by sequences shared between the DR4 and DRw6 haplotypes or by different sequences in these haplotypes. We have examined the distribution of DR and DQ beta-chain ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.85.10.3504

    authors: Scharf SJ,Friedmann A,Brautbar C,Szafer F,Steinman L,Horn G,Gyllensten U,Erlich HA

    更新日期:1988-05-01 00:00:00

  • The long cytoplasmic tail of gp41 is required in a cell type-dependent manner for HIV-1 envelope glycoprotein incorporation into virions.

    abstract::Lentiviruses, including HIV-1, have transmembrane envelope (Env) glycoproteins with cytoplasmic tails that are quite long compared with those of other retroviruses. However, mainly because of the lack of biochemical studies performed in cell types that are targets for HIV-1 infection, no clear consensus exists regardi...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.97.1.343

    authors: Murakami T,Freed EO

    更新日期:2000-01-04 00:00:00

  • Transductional and structural principles of the mitochondrial transducing unit.

    abstract::The electromechanochemical model has been reformulated to take account of the close connection between energy coupling and catalysis. In catalysis the protein is programmed to utilize thermal energy to produce local strains in the catalytic cavity and to generate conformational states that favor substrate --> product ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.70.3.904

    authors: Green DE,Ji S

    更新日期:1973-03-01 00:00:00

  • A glycoprotein associated with the non-A, non-B hepatitis agent(s): isolation and immunoreactivity.

    abstract::A glycoprotein was isolated and purified to homogeneity from the serum of a patient with chronic non-A, non-B hepatitis. NaDodSO4/PAGE of the glycoprotein revealed a single major band at Mr approximately 77,000. Antibodies to this glycoprotein were shown to possess the following immunoreactivity: (i) they reacted by r...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.82.15.4934

    authors: Seto B,Gerety RJ

    更新日期:1985-08-01 00:00:00

  • An in vivo correlate of exercise-induced neurogenesis in the adult dentate gyrus.

    abstract::With continued debate over the functional significance of adult neurogenesis, identifying an in vivo correlate of neurogenesis has become an important goal. Here we rely on the coupling between neurogenesis and angiogenesis and test whether MRI measurements of cerebral blood volume (CBV) provide an imaging correlate o...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0611721104

    authors: Pereira AC,Huddleston DE,Brickman AM,Sosunov AA,Hen R,McKhann GM,Sloan R,Gage FH,Brown TR,Small SA

    更新日期:2007-03-27 00:00:00

  • Phospholipase D is present on Golgi-enriched membranes and its activation by ADP ribosylation factor is sensitive to brefeldin A.

    abstract::ADP ribosylation factor (ARF) is a small guanosine triphosphate (GTP)-binding protein that regulates the binding of coat proteins to membranes and is required for several stages of vesicular transport. ARF also stimulates phospholipase D (PLD) activity, which can alter the lipid content of membranes by conversion of p...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.92.11.4952

    authors: Ktistakis NT,Brown HA,Sternweis PC,Roth MG

    更新日期:1995-05-23 00:00:00

  • Resources and energetics determined dinosaur maximal size.

    abstract::Some dinosaurs reached masses that were approximately 8 times those of the largest, ecologically equivalent terrestrial mammals. The factors most responsible for setting the maximal body size of vertebrates are resource quality and quantity, as modified by the mobility of the consumer, and the vertebrate's rate of ene...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0904000106

    authors: McNab BK

    更新日期:2009-07-21 00:00:00

  • Dependence of antibody-mediated presentation of antigen on FcRn.

    abstract::The neonatal Fc receptor for IgG (FcRn) is a distant member of the MHC class I protein family. It binds IgG and albumin in a pH-dependent manner and protects these from catabolism by diverting them from a degradative fate in lysosomes. In addition, FcRn-mediated IgG transport across epithelial barriers is responsible ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0801717105

    authors: Qiao SW,Kobayashi K,Johansen FE,Sollid LM,Andersen JT,Milford E,Roopenian DC,Lencer WI,Blumberg RS

    更新日期:2008-07-08 00:00:00

  • Resistance of simian virus 40-transformed hamster cells to the cytolytic effect of activated macrophages: a possible factor in species-specific viral oncogenicity.

    abstract::Simian virus 40 (SV40)-transformed hamster cells were relatively resistant to the lytic effect of activated macrophages from animals with chronic intracellular infections. Conversely, SV40-transformed mouse and rat cells and adenovirus 2-transformed hamster cells were highly susceptible to destruction by tumoricidal a...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.77.11.6773

    authors: Cook JL,Hibbs JB Jr,Lewis AM Jr

    更新日期:1980-11-01 00:00:00

  • Synergistic malaria vaccine combinations identified by systematic antigen screening.

    abstract::A highly effective vaccine would be a valuable weapon in the drive toward malaria elimination. No such vaccine currently exists, and only a handful of the hundreds of potential candidates in the parasite genome have been evaluated. In this study, we systematically evaluated 29 antigens likely to be involved in erythro...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.1702944114

    authors: Bustamante LY,Powell GT,Lin YC,Macklin MD,Cross N,Kemp A,Cawkill P,Sanderson T,Crosnier C,Muller-Sienerth N,Doumbo OK,Traore B,Crompton PD,Cicuta P,Tran TM,Wright GJ,Rayner JC

    更新日期:2017-11-07 00:00:00

  • Reversible oxidation and inactivation of the tumor suppressor PTEN in cells stimulated with peptide growth factors.

    abstract::Stimulation of cells with various peptide growth factors induces the production of phosphatidylinositol 3,4,5-trisphosphate (PIP3) through activation of phosphatidylinositol 3-kinase. The action of this enzyme is reversed by that of the tumor suppressor PTEN. With the use of cells overexpressing NADPH oxidase 1 or per...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0407396101

    authors: Kwon J,Lee SR,Yang KS,Ahn Y,Kim YJ,Stadtman ER,Rhee SG

    更新日期:2004-11-23 00:00:00

  • Early stages in DNA binding and uptake during genetic transformation of pneumococci.

    abstract::Ethylenediaminetetraacetate and other divalent-cation-complexing agents greatly stimulate the cellular binding of DNA molecules to competent pneumococci, while the appearance of genetic transformants and nuclease-resistant DNA binding are completely inhibited. Based on this finding, we developed an experimental system...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.71.4.1493

    authors: Seto H,Tomasz A

    更新日期:1974-04-01 00:00:00

  • Critical role of oxidative stress in estrogen-induced carcinogenesis.

    abstract::Mechanisms of estrogen-induced tumorigenesis in the target organ are not well understood. It has been suggested that oxidative stress resulting from metabolic activation of carcinogenic estrogens plays a critical role in estrogen-induced carcinogenesis. We tested this hypothesis by using an estrogen-induced hamster re...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0437929100

    authors: Bhat HK,Calaf G,Hei TK,Loya T,Vadgama JV

    更新日期:2003-04-01 00:00:00

  • Negative membrane curvature as a cue for subcellular localization of a bacterial protein.

    abstract::Bacterial proteins often localize to distinct sites within the cell, but the primary cues that dictate localization are largely unknown. Recent evidence has shown that positive membrane curvature can serve as a cue for localization of a peripheral membrane protein. Here we report that localization of the peripheral me...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0906851106

    authors: Ramamurthi KS,Losick R

    更新日期:2009-08-11 00:00:00

  • Nucleotide sequence of the Salmonella typhimurium origin of DNA replication.

    abstract::Construction of deletion derivative plasmids and cloning of restriction fragments from plasmids containing the Salmonella typhimurium origin of replication (ori) were used to locate the functional origin to within a DNA fragment of 296 base pairs between the genes uncB and asn. The nucleotide sequence of the S. typhim...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.77.5.2460

    authors: Zyskind JW,Smith DW

    更新日期:1980-05-01 00:00:00

  • Human CD8+ T cells do not require the polarization of lipid rafts for activation and proliferation.

    abstract::Lipid rafts are important signaling platforms in T cells. Little is known about their properties in human CD8(+) T cells. We studied polarization of lipid rafts by digital immunofluorescence microscopy in primary human T cells, using beads coated with anti-CD3 and anti-CD28 mAbs (CD3/28 beads). Unlike CD4(+) T cells, ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.232058599

    authors: Kovacs B,Maus MV,Riley JL,Derimanov GS,Koretzky GA,June CH,Finkel TH

    更新日期:2002-11-12 00:00:00

  • Gas-phase water-mediated equilibrium between methylglyoxal and its geminal diol.

    abstract::In aqueous solution, aldehydes, and to a lesser extent ketones, hydrate to form geminal diols. We investigate the hydration of methylglyoxal (MG) in the gas phase, a process not previously considered to occur in water-restricted environments. In this study, we spectroscopically identified methylglyoxal diol (MGD) and ...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.0912121107

    authors: Axson JL,Takahashi K,De Haan DO,Vaida V

    更新日期:2010-04-13 00:00:00

  • A highly conserved sequence is a novel gene involved in de novo vitamin B6 biosynthesis.

    abstract::The Cercospora nicotianae SOR1 (singlet oxygen resistance) gene was identified previously as a gene involved in resistance of this fungus to singlet-oxygen-generating phototoxins. Although homologues to SOR1 occur in organisms in four kingdoms and encode one of the most highly conserved proteins yet identified, the pr...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.96.16.9374

    authors: Ehrenshaft M,Bilski P,Li MY,Chignell CF,Daub ME

    更新日期:1999-08-03 00:00:00

  • Alkane biosynthesis by decarbonylation of aldehydes catalyzed by a particulate preparation from Pisum sativum.

    abstract::Mechanism of enzymatic conversion of a fatty acid to the corresponding alkane by the loss of the carboxyl carbon was investigated with particulate preparations from Pisum sativum. A heavy particulate preparation (sp. gr., 1.30 g/cm3) isolated by two density-gradient centrifugation steps catalyzed conversion of octadec...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.81.21.6613

    authors: Cheesbrough TM,Kolattukudy PE

    更新日期:1984-11-01 00:00:00

  • Splitting CO2 into CO and O2 by a single catalyst.

    abstract::The metal complex [(tpy)(Mebim-py)Ru(II)(S)](2+) (tpy = 2,2' : 6',2''-terpyridine; Mebim-py = 3-methyl-1-pyridylbenzimidazol-2-ylidene; S = solvent) is a robust, reactive electrocatalyst toward both water oxidation to oxygen and carbon dioxide reduction to carbon monoxide. Here we describe its use as a single electroc...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.1203122109

    authors: Chen Z,Concepcion JJ,Brennaman MK,Kang P,Norris MR,Hoertz PG,Meyer TJ

    更新日期:2012-09-25 00:00:00

  • Direct measurement of oligonucleotide substrate binding to wild-type and mutant ribozymes from Tetrahymena.

    abstract::Like protein enzymes, RNA enzymes (ribozymes) provide specific binding sites for their substrates. We now show that equilibrium dissociation constants for complexes between the Tetrahymena ribozyme and its RNA substrates and products can be directly measured by electrophoresis in polyacrylamide gels containing divalen...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.87.21.8187

    authors: Pyle AM,McSwiggen JA,Cech TR

    更新日期:1990-11-01 00:00:00

  • Polarons in DNA.

    abstract::Many experiments have been done to determine how far and how freely holes can move along the stack of base pairs in DNA. The results of these experiments are usually described in terms of a parameter beta under the assumption that it describes an exponential decay with distance. The reported values range from beta < 0...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.050074497

    authors: Conwell EM,Rakhmanova SV

    更新日期:2000-04-25 00:00:00

  • The Drosophila homologue of vertebrate myogenic-determination genes encodes a transiently expressed nuclear protein marking primary myogenic cells.

    abstract::We have isolated a cDNA clone, called Dmyd for Drosophila myogenic-determination gene, that encodes a protein with structural and functional characteristics similar to the members of the vertebrate MyoD family. Dmyd clone encodes a polypeptide of 332 amino acids with 82% identity to MyoD in the 41 amino acids of the p...

    journal_title:Proceedings of the National Academy of Sciences of the United States of America

    pub_type: 杂志文章

    doi:10.1073/pnas.88.9.3782

    authors: Paterson BM,Walldorf U,Eldridge J,Dübendorfer A,Frasch M,Gehring WJ

    更新日期:1991-05-01 00:00:00