A5059077470- Molecular Junctions and Nanostructures
- Force Microscopy Techniques and Applications
- Carbon Nanotubes in Composites
- Electrochemical Analysis and Applications
- Radiation Detection and Scintillator Technologies
- Graphene research and applications
- Advanced biosensing and bioanalysis techniques
- Nanotechnology research and applications
- 2D Materials and Applications
- X-ray Spectroscopy and Fluorescence Analysis
- X-ray Diffraction in Crystallography
- Advanced Memory and Neural Computing
- Medical Imaging Techniques and Applications
- Conducting polymers and applications
- Quantum-Dot Cellular Automata
- Nanowire Synthesis and Applications
- Advanced Chemical Physics Studies
- Nanoparticle-Based Drug Delivery
- Iron oxide chemistry and applications
- Anodic Oxide Films and Nanostructures
- Spectroscopy and Quantum Chemical Studies
- Photoreceptor and optogenetics research
- Particle Detector Development and Performance
- Surface Chemistry and Catalysis
- Crystallography and Radiation Phenomena
Florida State University
2023
Louisiana Tech University
2008-2022
Grambling State University
2008-2018
United States Air Force Research Laboratory
2018
University of Dayton
2018
Purdue University West Lafayette
2010
North Carolina Agricultural and Technical State University
2010
University of South Carolina
1999-2004
Texas A&M University
2004
Universidad Nacional de Córdoba
1995-2003
Green function and density functional theories are used to study electron transport characteristics through single molecules addressed by two metallic contacts. Each contact is modeled with one nan...
A proposed dinitro device, Au-(2′-nitro-4-ethynylphenyl-4′-ethynylphenyl-5′-nitro-1-benzene thiolate)-Au is analyzed using a combination of density functional and Green function theories complemented with information from theoretical experimental studies similar nitroamino Au-(2′-amino-4-ethynylphenyl-4′-ethynylphenyl-5′-nitro-1-benzenethiolate)-Au. The compound might also perform as molecular memory but different characteristics than those the nitroamino, showing well-defined charge states;...
The electrical behavior of π-conjugated oligo(phenyleneethynylene) systems functioning as memory devices is studied using quantum chemistry methods, including density functional and Green function formalisms combined in a fully self-consistent manner. Electron charge alters molecule impedance characteristic providing some cases distinguishable "impedance states" that can serve to determine experimentally the state molecule. Conducting nonconducting states be strategically engineered by...
Identifying the factors that trigger current-switching behavior of single molecules establishes means by which it may be possible to tailor these perform as electronic devices. We provide a theoretical interpretation switching observed in recent experiments with using quantum chemistry tools. conclude experiment is mostly due conformational changes and some charge cannot STM experiments.
Geometric and electronic properties of planar configurations Cu−Ni clusters containing up to five atoms are studied using density functional theory with effective core potentials, focusing on the differences between mono bimetallic clusters. Reactivity is examined by testing hydrogen adsorption bridge on-top sites. It found that geometric effects have strong effect reactivity; however, significant Cu Ni atomic structures factors nucleation, stability, properties.
This brief presents a molecular dynamics study on device proposed for terahertz signal processing. We conclude that signals following the movement of gold clusters attached to molecules can modulate vibrational modes in spectrum internal coordinates defining bonds. It is shown, by using intensities involved natural modes, which are experimentally recoverable spectroscopy measurements, we recover components due couplings between local and, thus, provide computational proof possibility...
A density functional theory study of copper clusters is presented. Fully optimized geometries, electronic structures, HOMO−LUMO gaps, spin distributions, and ionization potentials are reported. The systematic starting with one-dimensional followed by several planar structures three-dimensional systems chosen to emulate (100) (111) planes bulk Cu. For the 1-D systems, it found that dissociation energy potential follow an oscillatory behavior reflects a conjugate-like character indicative...
Molecular electronics can be developed if we are able to program a random arrangement of molecules or field-programmable molecular array. The ansatz that small programmed needs demonstrated; this means characterizing the smallest system with programmable features. We demonstrate even two in series conformation have multivalued responses and, thus, is programmed; also indicate how extend programmability other circuit conformations. Current programs for calculation current-voltage...
A detailed study of agglomeration in composite materials containing carbon nanotubes (CNT) is presented. Three dimensional samples with different degrees were created three ways, leading to a wider range geometries available study. Virtual charges are injected into the computer-generated and move through these according Monte Carlo hopping algorithm. Results show that there an optimal level actually beneficial for charge transport at low volume concentrations, lowering percolation threshold....
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTMolecular Gain in a Thiotolane SystemJorge M. Seminario and Pedro A. DerosaView Author Information Department of Electrical Engineering University South Carolina Columbia, 29208 Cite this: J. Am. Chem. Soc. 2001, 123, 49, 12418–12419Publication Date (Web):November 10, 2001Publication History Received20 May 2001Published online10 November inissue 1 December 2001https://doi.org/10.1021/ja0162313Copyright © 2001 American Chemical SocietyRIGHTS &...
The 3-nitro-2-(3‘-nitro-2‘-ethynylpyridine)-5-thiopyridine molecule shows charge-induced conformational switching and a rectifying behavior with controllable switching. This device can be used as memory operated an external field interacting one of the rings local dipole. Alternatively, nano-actuator controlling rotation ring by charging bias voltage.
Using quantum ab initio techniquesa theoretical "microscope"we demonstrate that molecules of nanometer sizes can be characterized as low and high impedance devices, needed building blocks in the field molecular electronics. Small alkanes polyynes chains with σ π bonding, respectively, yield a high-low relation 2 orders magnitude at 1-nm length 3 1.3-nm length. For these small chains, it is concluded no simple trends conductance versus determined. We also successfully test our methods against...
A lattice‐gas model including intralayer and interlayer interactions is used to study the intercalation of lithium in graphite. The able reproduce characteristic staging phenomena observed formation compounds. Three parameters describing main energetic entropic are found necessary most experimental features. © 1999 Electrochemical Society. All rights reserved.
A Monte Carlo model is used to study the effect of environmental variables (pH and temperature) on transport release dexamethasone molecules from Halloysite Nanotubes (HNTs) in a dielectric fluid medium. The for this was introduced elsewhere it based basic physics interactions without experimental parameters these interactions. An intermediate phase between burst saturation found explained. Molecules experience 1-D diffusion process that different or surface experienced by attached wall. It...
Protocols for nanopatterning porphyrins on Au(111) were developed based immersion particle lithography. Porphyrins with and without a central metal ion, 5,10,15,20-tetraphenyl-21H,23H-porphyrin (TPP) cobalt(II) (CoTPP), selected study, which spontaneously formed nanorod geometries depending concentration parameters. The elongated shapes of the nanorods offers an opportunity successive distance-dependent conductive probe atomic force microscopy (CP-AFM) measurements along length nanorods. To...
An approach for printing micron-scale electronic devices built from two-dimensional materials is presented. Experimental phage display techniques and computational atomistic simulation approaches were used to identify a peptide molecule that effectively anchors the basal plane surface of (2D) MoS2 SiO2 surfaces. This was suspended in water develop an ink suitable aerosol jet printing. The printed substrates then dip coated with suspension liquid phase exfoliated 2D particles. Strong adhesion...
Building upon psychological momentum theory, we draw an analogy between motivational constructs proposed herein and the physical principles of mass, inertia, momentum. From these principles, derived representing academic inertia in states both low high The sample consisted 105 African American college students science, technology, engineering, mathematics majors. Results a confirmatory factor analysis (CFA) newly developed scale yielded support for two distinct factors reflecting state...
The simple equation used to calculate the intrinsic photopeak efficiency of a semiconductor germanium detector consisting one factor which allows for x-ray transmission through window and another takes into account photoelectric interaction in active volume has proved be insufficient since it does not consider escape photons with characteristic line energies. An analytical expression embodying all physical processes photon interaction, including photons, is proposed; such an corrects...