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Adam M. Rawlett

Other affiliations: Rice University, Yale University, Motorola  ...read more
Bio: Adam M. Rawlett is an academic researcher from United States Army Research Laboratory. The author has contributed to research in topics: Molecular electronics & Molecular memory. The author has an hindex of 26, co-authored 53 publications receiving 6806 citations. Previous affiliations of Adam M. Rawlett include Rice University & Yale University.


Papers
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Journal ArticleDOI
19 Nov 1999-Science
TL;DR: A molecule containing a nitroamine redox center was used in the active self-assembled monolayer in an electronic device that exhibited negative differential resistance and an on-off peak-to-valley ratio in excess of 1000:1.
Abstract: A molecule containing a nitroamine redox center (2'-amino-4-ethynylphenyl-4'-ethynylphenyl-5'-nitro-1-benzenethiol) was used in the active self-assembled monolayer in an electronic device. Current-voltage measurements of the device exhibited negative differential resistance and an on-off peak-to-valley ratio in excess of 1000:1.

2,295 citations

Journal ArticleDOI
22 Jun 2001-Science
TL;DR: Over time the conductance switching of single and bundled phenylene ethynylene oligomers isolated in matrices of alkanethiolate monolayers is tracked, concluding that the switching is a result of conformational changes in the molecules or bundles, rather than electrostatic effects of charge transfer.
Abstract: We tracked over time the conductance switching of single and bundled phenylene ethynylene oligomers isolated in matrices of alkanethiolate monolayers. The persistence times for isolated and bundled molecules in either the ON or OFF switch state range from seconds to tens of hours. When the surrounding matrix is well ordered, the rate at which the inserted molecules switch is low. Conversely, when the surrounding matrix is poorly ordered, the inserted molecules switch more often. We conclude that the switching is a result of conformational changes in the molecules or bundles, rather than electrostatic effects of charge transfer.

1,158 citations

Journal ArticleDOI
TL;DR: In this article, electronic programmable and erasable memory bits compatible with conventional threshold levels and a memory cell applicable to a random access memory have been demonstrated, with bit retention times > 15 min.
Abstract: Electronically programmable memory devices utilizing molecular self-assembled monolayers are reported. The devices exhibit electronically programmable and erasable memory bits compatible with conventional threshold levels and a memory cell applicable to a random access memory is demonstrated. Bit retention times >15 min have been observed.

564 citations

Journal ArticleDOI
TL;DR: In this article, active self-assembled monolayers containing the nitroamine [2′-amino-4,4′-di(ethynylphenyl)-5′-nitro-1-benzenethiolate] or the Nitro compound [4, 4′-mino]-2.2.
Abstract: Molecular devices are reported utilizing active self-assembled monolayers containing the nitroamine [2′-amino-4,4′-di(ethynylphenyl)-5′-nitro-1-benzenethiolate] or the nitro compound [4,4′-di(ethynylphenyl)-2′-nitro-1-benzenethiolate] as the active components Both of these compounds have active redox centers Current–voltage measurements of the devices exhibited negative differential resistance at room temperature and an on–off peak-to-valley ratio in excess of 1000:1 at low temperature

479 citations

Journal ArticleDOI
30 May 2003-Science
TL;DR: It is argued that the cause of stochastic on-off switching in alkanethiols is the well-known mobility of molecules tethered to gold via a thiol linkage.
Abstract: Stochastic on-off conductivity switching observed in phenylene-ethynylene oligomers has been explained in terms of changes in ring conformations, or electron localization, or both. We report the observation of stochastic on-off switching in the simplest of wired molecules: octanedithiol, decanedithiol, and dodecanedithiol bonded on an Au(111) surface. Stochastic switching was observed even when a top gold contact was pressed on by a conducting atomic force microscope tip at constant force. The rate of switching increased substantially at 60°C, a temperature at which these films are commonly annealed. Because such switching in alkanethiols is unlikely to be caused by internal molecular electronic changes and cannot be fully accounted for by breaking of the top contact, we argue that the cause is the well-known mobility of molecules tethered to gold via a thiol linkage.

401 citations


Cited by
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Journal ArticleDOI
TL;DR: An overview of NWChem is provided focusing primarily on the core theoretical modules provided by the code and their parallel performance, as well as Scalable parallel implementations and modular software design enable efficient utilization of current computational architectures.

4,666 citations

Journal ArticleDOI
30 Nov 2000-Nature
TL;DR: ‘mono-molecular’ electronics, in which a single molecule will integrate the elementary functions and interconnections required for computation, is proposed.
Abstract: The semiconductor industry has seen a remarkable miniaturization trend, driven by many scientific and technological innovations. But if this trend is to continue, and provide ever faster and cheaper computers, the size of microelectronic circuit components will soon need to reach the scale of atoms or molecules—a goal that will require conceptually new device structures. The idea that a few molecules, or even a single molecule, could be embedded between electrodes and perform the basic functions of digital electronics—rectification, amplification and storage—was first put forward in the mid-1970s. The concept is now realized for individual components, but the economic fabrication of complete circuits at the molecular level remains challenging because of the difficulty of connecting molecules to one another. A possible solution to this problem is ‘mono-molecular’ electronics, in which a single molecule will integrate the elementary functions and interconnections required for computation.

2,853 citations

Journal ArticleDOI
TL;DR: A summary of the technical advances that are incorporated in the fourth major release of the Q-Chem quantum chemistry program is provided in this paper, covering approximately the last seven years, including developments in density functional theory and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces.
Abstract: A summary of the technical advances that are incorporated in the fourth major release of the Q-Chem quantum chemistry program is provided, covering approximately the last seven years. These include developments in density functional theory methods and algorithms, nuclear magnetic resonance (NMR) property evaluation, coupled cluster and perturbation theories, methods for electronically excited and open-shell species, tools for treating extended environments, algorithms for walking on potential surfaces, analysis tools, energy and electron transfer modelling, parallel computing capabilities, and graphical user interfaces. In addition, a selection of example case studies that illustrate these capabilities is given. These include extensive benchmarks of the comparative accuracy of modern density functionals for bonded and non-bonded interactions, tests of attenuated second order Moller–Plesset (MP2) methods for intermolecular interactions, a variety of parallel performance benchmarks, and tests of the accuracy of implicit solvation models. Some specific chemical examples include calculations on the strongly correlated Cr_2 dimer, exploring zeolite-catalysed ethane dehydrogenation, energy decomposition analysis of a charged ter-molecular complex arising from glycerol photoionisation, and natural transition orbitals for a Frenkel exciton state in a nine-unit model of a self-assembling nanotube.

2,396 citations

Journal ArticleDOI
TL;DR: This review describes recent advances in the synthesis of biomolecule-nanoparticle/nanorod hybrid systems and the application of such assemblies in the generation of 2D and 3D ordered structures in solutions and on surfaces.
Abstract: Nanomaterials, such as metal or semiconductor nanoparticles and nanorods, exhibit similar dimensions to those of biomolecules, such as proteins (enzymes, antigens, antibodies) or DNA. The integration of nanoparticles, which exhibit unique electronic, photonic, and catalytic properties, with biomaterials, which display unique recognition, catalytic, and inhibition properties, yields novel hybrid nanobiomaterials of synergetic properties and functions. This review describes recent advances in the synthesis of biomolecule-nanoparticle/nanorod hybrid systems and the application of such assemblies in the generation of 2D and 3D ordered structures in solutions and on surfaces. Particular emphasis is directed to the use of biomolecule-nanoparticle (metallic or semiconductive) assemblies for bioanalytical applications and for the fabrication of bioelectronic devices.

2,334 citations

PatentDOI
04 Jun 2001-Science
TL;DR: A method of constructing <30-nanometer structures in close proximity with precise spacings is presented that uses the step-by-step application of organic molecules and metal ions as size-controlled resists on predetermined patterns, such as those formed by electron-beam lithography.
Abstract: The present invention is a method and apparatus relating to manufacturing nanostructure patterns and components using molecular science. The method includes overlaying a multilayer organic molecule resist on at least a portion of a parent structure selectively deposited on a substrate, depositing a layer over the parent structure and in contact with at least a portion of the multilayer organic resist, and removing the multilayer organic molecule resist to leave a residual structure.

2,301 citations