A5074508309- Molecular Junctions and Nanostructures
- Electrochemical Analysis and Applications
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Organic Electronics and Photovoltaics
- Graphene research and applications
- Quantum Dots Synthesis And Properties
- Crystallography and molecular interactions
- Diamond and Carbon-based Materials Research
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanocluster Synthesis and Applications
- Force Microscopy Techniques and Applications
- Nanomaterials for catalytic reactions
- Analytical Chemistry and Sensors
- Nanowire Synthesis and Applications
- Spectroscopy and Quantum Chemical Studies
- Quantum and electron transport phenomena
- Synthesis and characterization of novel inorganic/organometallic compounds
- Nanopore and Nanochannel Transport Studies
- Plasma Diagnostics and Applications
- Advanced Physical and Chemical Molecular Interactions
- Semiconductor materials and devices
- Phase-change materials and chalcogenides
- Photoreceptor and optogenetics research
- Conducting polymers and applications
Uppsala University
2010-2015
KTH Royal Institute of Technology
2013
We have studied the effect of double-functionalization on gold electrodes for improving nanopore-based DNA sequencing. The functionalizing molecular probes are, respectively, capable temporarily forming hydrogen bonds with both nucleobase part and phosphate group target DNA, thus potentially minimizing structural fluctuations a single-stranded molecule passing between electrodes. results our first-principles study indicate that proposed setup yields current signals differ by at least 1 order...
We present calculated interband transitions and effective masses for diamond from first principles including electron correlation effects via the GW-approximation. Our findings are in agreement with experiments, already iteration of GW-scheme gives a direct gap at gamma-point 7.38 eV indirect 5.75 close to experimental values. For deeper bands quasiparticle self-consistent method is necessary accurately reproduce valence band width 23.1 eV. also obtain hole along different symmetry axes...
Abstract Cyclohexane, with its well‐defined conformers, could be an ideal force‐controlled molecular switch if it were to display substantial differences in electronic and optical properties between conformers. We utilize σ conjugation heavier analogues of cyclohexanes (i.e. cyclohexasilanes) show that 1,4‐disubstituted cyclohexasilanes configuration‐ conformation‐dependent variations these properties. Cis ‐ trans ‐1,4‐bis(trimethylsilylethynyl)cyclohexasilanes a 0.11 V difference their...
A series of tentative single-molecule conductance switches which could be triggered by light were examined computational means using density functional theory (DFT) with non-equilibrium Green's functions (NEGF). The exploit the reversal in electron counting rules for aromaticity and antiaromaticity upon excitation from electronic ground state (S<sub>0</sub>) to lowest ππ* excited singlet triplet states (S<sub>1</sub> or T<sub>1</sub>), as described Hückel's Baird's rules, respectively. Four...
Abstract Reproducibility, stability and the coupling between electrical molecular properties are central challenges in field of electronics. The not only needs devices that fulfill these criteria but they also need to be up-scalable application size. In this work, few-molecule based electronics with reproducible characteristics demonstrated. Our previously reported 5 nm gold nanoparticles (AuNP) coated ω-triphenylmethyl (trityl) protected 1,8-octanedithiol molecules trapped sub-20 gap...
Silicon is still the dominating material in microelectronics, yet primarily π-conjugated hydrocarbons are investigated field of single-molecule electronics even though linear oligosilanes σ-conjugated. A drawback with latter their high conformational flexibility which strongly affects conductance. Here we report on a first principles density functional theory investigation series rigid [2.2.2]bicyclic carbosilanes 3, 2, 1, or 0 disilanylene bridges, providing all-silicon paths for charge...
A combination of electron beam lithography, photolithography and focused ion milling was used to create a nanogap platform, which bridged by gold nanoparticles in order make electrical measurements assess the platform under ambient conditions. Non-functionalized electrodes were tested determine intrinsic response it found that creating devices conditions requires careful cleaning awareness contributions contaminants may measurements. The then on octanethiol (OT) biphenyldithiol (BPDT)...
In this article, we use hybrid density functional (HSE06) to study the crystal and electronic structures optical properties of well known phase change memory material $\mathrm{Ge_{2}Sb_{2}Te_{5}}$. We calculate structural parameters, band gaps dielectric functions three stable material. also analyze electron charge distribution using Bader's theory analysis. find that slightly overestimate value 'C' parameter. However, overall, our results calculated with are very close available...
Abstract Acetylenic phosphaalkenes (APAs) are used as a novel type of ligands for the stabilization gold nanoparticles (AuNP). As demonstrated by variety experimental and analytical methods, both structural features APA, that is, PC well CC units essential NP stabilization. The presence intact APAs on AuNP is surface‐enhanced Raman spectroscopy (SERS), first principle calculations indicate bonding occurs most likely at defect sites Au surface. AuNP‐bound in chemical equilibrium with free...
Short chains containing a series of metal–molecule–nanoparticle nanojunctions are nano-material system with the potential to give electrical signatures close those from single molecule experiments while enabling us build portable devices on chip. Inelastic electron tunnelling spectroscopy (IETS) measurements provide one most characteristic signals and few molecules. In interlinked molecule–nanoparticle (NP) typically 5–7 molecules in chain, spectrum is expected be superposition vibrational...
Oligomers of 1,4-disila/germa/stannacyclohexa-2,5-dienes as well all-carbon 1,4-cyclohexadienes connected via E—E single bonds (E = C, Si, Ge, or Sn) were studied through quantum chemical calculations in an effort to identify conformationally flexible molecular wires that act "electrical cords" having conformer-independent conjugative and conductive properties. Our oligomers display neutral hyperconjugative interactions (σ/π-conjugation) between adjacent σ(E—E) π(C═C) bond orbitals, these do...
On the basis of first-principles density functional theory calculations, we propose a new molecular photoswitch which exploits photochemical [1,3]-silyl(germyl) shift leading from silane to silene (a Si=C double bonded compound). The silanes investigated herein act as OFF state, with tetrahedral saturated silicon atoms disrupting conjugation through molecules. silenes, on other hand, have conjugated paths spanning over complete molecules and thus ON state. We calculate ON/OFF conductance...
Abstract Acetylenic phosphaalkenes (APAs) are used as a novel type of ligands for the stabilization gold nanoparticles (AuNP). As demonstrated by variety experimental and analytical methods, both structural features APA, that is, PC well CC units essential NP stabilization. The presence intact APAs on AuNP is surface‐enhanced Raman spectroscopy (SERS), first principle calculations indicate bonding occurs most likely at defect sites Au surface. AuNP‐bound in chemical equilibrium with free...
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Henrik Löfås, Anton Grigoriev, Jan Isberg, Rajeev Ahuja; Transport coefficients in diamond from ab-initio calculations. Appl. Phys. Lett. 4 March 2013; 102 (9): 092106. https://doi.org/10.1063/1.4794062 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks...
Click to increase image sizeClick decrease size Additional informationNotes on contributorsRajeev Ahuja(Chairman)