Journal articles: 'Molecule electronic properties'

1

Hersam, M. C., and R. G. Reifenberger. "Charge Transport through Molecular Junctions." MRS Bulletin 29, no. 6 (June 2004): 385–90. http://dx.doi.org/10.1557/mrs2004.120.

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AbstractIn conventional solid-state electronic devices, junctions and interfaces play a significant if not dominant role in controlling charge transport. Although the emerging field of molecular electronics often focuses on the properties of the molecule in the design and understanding of device behavior, the effects of interfaces and junctions are often of comparable importance. This article explores recent work in the study of metal–molecule–metal and semiconductor–molecule–metal junctions. Specific issues include the mixing of discrete molecular levels with the metal continuum, charge transfer between molecules and semiconductors, electron-stimulated desorption, and resonant tunneling. By acknowledging the consequences of junction/interface effects, realistic prospects and limitations can be identified for molecular electronic devices.

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LEE, Tak Hee, Hyunhak JEONG, and Wang-Taek HWANG. "Electronic Properties of Single-molecule Junctions." Physics and High Technology 22, no. 11 (November 30, 2013): 9. http://dx.doi.org/10.3938/phit.22.049.

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Al-Saidi, Shakir A. A., and Alaa Ayad K. Al-mebir. "Electronic Properties Simulation of Guanine Molecule." Journal of Physics: Conference Series 1530 (May 2020): 012148. http://dx.doi.org/10.1088/1742-6596/1530/1/012148.

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ERKOÇ, ŞAKİR, and FİLİZ KORKMAZ. "STRUCTURAL AND ELECTRONIC PROPERTIES OF THE DPPC MOLECULE." International Journal of Modern Physics C 17, no. 07 (July 2006): 967–74. http://dx.doi.org/10.1142/s0129183106009503.

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The structural and electronic properties of the DPPC molecule have been investigated theoretically by performing semi-empirical self-consistent-field molecular-orbital theory calculations at the PM3 level in its ground state.

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ÇALIŞIR, EMİNE DENİZ, and ŞAKİR ERKOÇ. "STRUCTURAL AND ELECTRONIC PROPERTIES OF DIPROPYL SULFIDE: A THEORETICAL INVESTIGATION." International Journal of Modern Physics C 17, no. 08 (August 2006): 1179–90. http://dx.doi.org/10.1142/s0129183106009588.

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The structural, vibrational, electronic and QSAR properties of the dipropyl sulfide (DPS) molecule in gas phase have been investigated theoretically by performing semi-empirical molecular orbital (AM1 and PM3), ab initio (RHF) and density functional theory calculations. The geometry of the molecule has been optimized, infrared spectrum (vibrational modes and intensities) and the electronic properties of the molecule have been calculated in its ground state. It has been found that DPS molecule kinetically may not be stable however it is thermodynamically stable.

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YU, XIAOQING, CONGJUN WU, CHUI-LIN WANG, and ZHAO-BIN SU. "ELECTRONIC AND STRUCTURAL PROPERTIES OF C36 MOLECULE." International Journal of Modern Physics B 13, no. 12 (May 20, 1999): 1513–23. http://dx.doi.org/10.1142/s0217979299001557.

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The extended SSH model and Bogoliubov–de–Gennes (BdeG) formalism are applied to investigate the electronic properties and stable lattice configurations of C 36. We focus the problem on the molecule's unusual D6h symmetry. The electronic part of Hamiltonian without Coulomb interaction is solved analytically. We found that the gap between HOMO and LUMO is small due to the long distance hopping between the 2nd and 5th layers. The charge densities of HOMO and LUMO states are mainly distributed in the two layers, that causes a large splitting between the spin triplet and singlet excitons. The differences of bond lengths, angles and charge densities among molecule and polarons are discussed.

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Luka-Guth, Katharina, Sebastian Hambsch, Andreas Bloch, Philipp Ehrenreich, Bernd Michael Briechle, Filip Kilibarda, Torsten Sendler, et al. "Role of solvents in the electronic transport properties of single-molecule junctions." Beilstein Journal of Nanotechnology 7 (July 22, 2016): 1055–67. http://dx.doi.org/10.3762/bjnano.7.99.

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We report on an experimental study of the charge transport through tunnel gaps formed by adjustable gold electrodes immersed into different solvents that are commonly used in the field of molecular electronics (ethanol, toluene, mesitylene, 1,2,4-trichlorobenzene, isopropanol, toluene/tetrahydrofuran mixtures) for the study of single-molecule contacts of functional molecules. We present measurements of the conductance as a function of gap width, conductance histograms as well as current–voltage characteristics of narrow gaps and discuss them in terms of the Simmons model, which is the standard model for describing transport via tunnel barriers, and the resonant single-level model, often applied to single-molecule junctions. One of our conclusions is that stable junctions may form from solvents as well and that both conductance–distance traces and current–voltage characteristics have to be studied to distinguish between contacts of solvent molecules and of molecules under study.

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XUE, YONG, and G. ALI MANSOORI. "QUANTUM CONDUCTANCE AND ELECTRONIC PROPERTIES OF LOWER DIAMONDOID MOLECULES AND DERIVATIVES." International Journal of Nanoscience 07, no. 01 (February 2008): 63–72. http://dx.doi.org/10.1142/s0219581x08005183.

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Diamondoids and their derivatives have found major applications as templates and as molecular building blocks in nanotechnology. An ab initio method we calculated the quantum conductance and the essential electronic properties of two lower diamondoids (adamantane and diamantane) and three of their important derivatives (amantadine, memantine and rimantadine). We also studies two artificial molecules that are built by substituting one hydrogen ion with one sodium ion in both adamantane and diamantane molecules. Most of our results are based on an infinite Au two-probe system constructed by ATK and VNL software, which comprise TRANSTA-C package. By changing various system structures and molecule orientations in linear Au and 2 × 2 Au probe systems, we found that although the conductance of adamantane and diamantane are very small, the derivatives of the lower diamondoids have considerable conductance at specific orientations and also showed interesting electronic properties. The quantum conductance of such molecules will change significantly by changing the orientations of the molecules, which approves that residues like nitrogen and sodium atoms have great effects on the conductance and electronic properties of single molecule. There are obvious peaks near Fermi energy in the transmission spectrums of artificial molecules, indicating the plateaus in I–V characteristics of such molecules.

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Reimers, Jeffrey R., Ante Bilić, Zheng-Li Cai, Mats Dahlbom, Nicholas A. Lambropoulos, Gemma C. Solomon, Maxwell J. Crossley, and Noel S. Hush. "Molecular Electronics: From Basic Chemical Principles to Photosynthesis to Steady-State Through-Molecule Conductivity to Computer Architectures." Australian Journal of Chemistry 57, no. 12 (2004): 1133. http://dx.doi.org/10.1071/ch04132.

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Molecular electronics offers many possibilities for the development of electronic devices beyond the limit of silicon technology. Its basic ideas and history are reviewed, and a central aspect of the delocalization of electrons across molecules and junctions is examined. Analogies between key processes affecting steady-state through-molecule conduction and equilibrium geometric and spectroscopic properties of paradigm molecules, such as hydrogen, ammonia, benzene, and the Creutz–Taube ion are drawn, and the mechanisms by which control can be exerted over molecular-electronic processes during biological photosynthesis are examined. Ab initio molecular dynamics and simulations of conductivity are then presented for carbon nanotube flanged to gold(111), and device characteristics are calculated for a molecular shift register clocked by two gold electrodes.

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Pal, Atindra Nath, Tal Klein, Ayelet Vilan, and Oren Tal. "Electronic conduction during the formation stages of a single-molecule junction." Beilstein Journal of Nanotechnology 9 (May 17, 2018): 1471–77. http://dx.doi.org/10.3762/bjnano.9.138.

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Single-molecule junctions are versatile test beds for electronic transport at the atomic scale. However, not much is known about the early formation steps of such junctions. Here, we study the electronic transport properties of premature junction configurations before the realization of a single-molecule bridge based on vanadocene molecules and silver electrodes. With the aid of conductance measurements, inelastic electron spectroscopy and shot noise analysis, we identify the formation of a single-molecule junction in parallel to a single-atom junction and examine the interplay between these two conductance pathways. Furthermore, the role of this structure in the formation of single-molecule junctions is studied. Our findings reveal the conductance and structural properties of premature molecular junction configurations and uncover the different scenarios in which a single-molecule junction is formed. Future control over such processes may pave the way for directed formation of preferred junction structures.

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Erkoç, Şakir, Sibel Sümer, and Figen Erkoç. "Structural and electronic properties of ajoene molecule." Journal of Molecular Structure: THEOCHEM 631, no. 1-3 (August 2003): 271–76. http://dx.doi.org/10.1016/s0166-1280(03)00259-8.

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12

Seenithurai, Sonai, Ramalingam Kodi Pandyan, Shanmugam Vinodh Kumar, and Manickam Mahendran. "Electronic Properties of Boron and Nitrogen Doped Graphene." Nano Hybrids 5 (October 2013): 65–83. http://dx.doi.org/10.4028/www.scientific.net/nh.5.65.

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Graphene is the thinnest 2-D material which can be regarded as a single layer of graphite. The unique electrical, mechanical and optical properties of graphene can be used in many technological applications. 2-D nanomaterials with semiconducting properties are of great interest since they can be applied in electronics industry. Pure graphene is a zerogap semiconductor or semimetal, since the electron states just cross the Fermi energy. However, the electronic properties of graphene can be tuned by doping boron or nitrogen atoms. Understanding the electronic properties in terms of density of states and band structure of doped graphene is of great relevance today. In our work, we have analyzed the electronic properties of boron and nitrogen doped graphene using Density Functional Theory (DFT). The stability and charge analysis of doped structures have been studied. The Local Density Approximation (LDA) calculations have been used to find the total energies of the structures. In addition to the electronics industry, doped graphene also has great potential to adsorb gas molecules. Therefore, we have analyzed the H2 molecule adsorption in pure, B-doped and N-doped graphene.

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Kafi, Dhaidan Khalaf. "Molecular Structure, Electronic and Spectral Properties Study of N, N-bis (2- Hydroxybenzalidene1, 3-Diamino-2-Propanol) Aromatic Molecule Using DFT Theory." International Journal of Psychosocial Rehabilitation 24, no. 4 (April 30, 2020): 6290–300. http://dx.doi.org/10.37200/ijpr/v24i4/pr2020438.

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14

Wang, Kun, Joseph Hamill, Jianfeng Zhou, Cunlan Guo, and Bingqian Xu. "Measurement and control of detailed electronic properties in a single molecule break junction." Faraday Discuss. 174 (2014): 91–104. http://dx.doi.org/10.1039/c4fd00080c.

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The lack of detailed experimental controls has been one of the major obstacles hindering progress in molecular electronics. While large fluctuations have been occurring in the experimental data, specific details, related mechanisms, and data analysis techniques are in high demand to promote our physical understanding at the single-molecule level. A series of modulations we recently developed, based on traditional scanning probe microscopy break junctions (SPMBJs), have helped to discover significant properties in detail which are hidden in the contact interfaces of a single-molecule break junction (SMBJ). For example, in the past we have shown that the correlated force and conductance changes under the saw tooth modulation and stretch–hold mode of PZT movement revealed inherent differences in the contact geometries of a molecular junction. In this paper, using a bias-modulated SPMBJ and utilizing emerging data analysis techniques, we report on the measurement of the altered alignment of the HOMO of benzene molecules with changing the anchoring group which coupled the molecule to metal electrodes. Further calculations based on Landauer fitting and transition voltage spectroscopy (TVS) demonstrated the effects of modulated bias on the location of the frontier molecular orbitals. Understanding the alignment of the molecular orbitals with the Fermi level of the electrodes is essential for understanding the behaviour of SMBJs and for the future design of more complex devices. With these modulations and analysis techniques, fruitful information has been found about the nature of the metal–molecule junction, providing us insightful clues towards the next step for in-depth study.

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SU, WEN-YONG, YAN-PING JIN, and FENG WANG. "QUANTUM CHEMICAL STUDY OF ELECTRONIC TRANSPORT PROPERTIES OF BIPHENYLDITHIOL MOLECULAR JUNCTION." Modern Physics Letters B 23, no. 28 (November 10, 2009): 3341–51. http://dx.doi.org/10.1142/s0217984909021399.

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Applying the elastic scattering Green's function theory in combination with the frontier molecular orbital theory for describing the surface-molecule coupling and hybrid density-function theory for geometrical and electronic structure calculations, we successfully reproduce the current–voltage properties of the 4,4-biphenyldithiol molecular junction, which has been measured using a lock-in technique by Lee et al.1 We also analyze the conductance characteristics of different dimensional electrodes in contact with the molecular device, and we think that the one-dimensional formula is consistent with the experiment, and that the interaction between neighboring molecules will decrease the molecular orbital energies and draw the conductance peak positions closer to experimental results.

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Wen, Huimin, Wengang Li, Jiewei Chen, Gen He, Longhua Li, Mark A. Olson, Andrew C. H. Sue, J. Fraser Stoddart, and Xuefeng Guo. "Complex formation dynamics in a single-molecule electronic device." Science Advances 2, no. 11 (November 2016): e1601113. http://dx.doi.org/10.1126/sciadv.1601113.

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Single-molecule electronic devices offer unique opportunities to investigate the properties of individual molecules that are not accessible in conventional ensemble experiments. However, these investigations remain challenging because they require (i) highly precise device fabrication to incorporate single molecules and (ii) sufficient time resolution to be able to make fast molecular dynamic measurements. We demonstrate a graphene-molecule single-molecule junction that is capable of probing the thermodynamic and kinetic parameters of a host-guest complex. By covalently integrating a conjugated molecular wire with a pendent crown ether into graphene point contacts, we can transduce the physical [2]pseudorotaxane (de)formation processes between the electron-rich crown ether and a dicationic guest into real-time electrical signals. The conductance of the single-molecule junction reveals two-level fluctuations that are highly dependent on temperature and solvent environments, affording a nondestructive means of quantitatively determining the binding and rate constants, as well as the activation energies, for host-guest complexes. The thermodynamic processes reveal the host-guest binding to be enthalpy-driven and are consistent with conventional 1H nuclear magnetic resonance titration experiments. This electronic device opens up a new route to developing single-molecule dynamics investigations with microsecond resolution for a broad range of chemical and biochemical applications.

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Pahuja, Akshu, and Sunita Srivastava. "Electronic Transport Properties of Doped C28 Fullerene." Physics Research International 2014 (November 26, 2014): 1–7. http://dx.doi.org/10.1155/2014/872381.

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Endohedral doping of small fullerenes like C28 affects their electronic structure and increases their stability. The transport properties of Li@C28 sandwiched between two gold surfaces have been calculated using first-principles density functional theory and nonequilibrium Green’s function formalism. The transmission curves, IV characteristics, and molecular projected self-consistent Hamiltonian eigenstates of both pristine and doped molecule are computed. The current across the junction is found to decrease upon Li encapsulation, which can be attributed to change in alignment of molecular energy levels with bias voltage.

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Masan, Samuel E. P. P., Fitri N. Febriana, Andi H. Zaidan, Ira Puspitasari, and Febdian Rusydi. "Evaluation of the Electronic Structure Resulting from ab-initio Calculations on Simple Molecules Using the Molecular Orbital Theory." Jurnal Penelitian Pendidikan IPA 7, no. 1 (January 28, 2021): 107. http://dx.doi.org/10.29303/jppipa.v7i1.545.

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Hartree Fock (HF) and Density Functional Theory (DFT) have been commonly used to model chemical problems. This study uses the Molecular Orbital Theory (MOT) to evaluate the electronic structure of five diatomic molecules generated by HF and DFT calculations. The evaluation provides an explanation of how the orbitals of a molecule come to be and how this affects the calculation of the physical quantities of the molecule. The evaluation is obtained after comparing the orbital wave functions calculated by MOT, HF, and DFT. This study found that the nature of the Highest Occupied Molecular Orbital (HOMO) of a molecule is determined by the valence orbital properties of the constituent atoms. This HOMO property greatly influences the precision of calculating the molecular electric dipole moment. This shows the importance of understanding the orbital properties of a molecule formed from the HF and DFT calculations

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Essa, Ali Hashem, and A. F. Jalbout. "Analysis of the structural and electronic properties of 1-(5-Hydroxymethyl - 4 –[ 5 – (5-oxo-5-piperidin-1-yl-penta- 1,3dienyl)-benzo[1,3]dioxol-2-yl] -tetrahydro-furan-2-yl)-5- methyl-1H-pyrimidine-2,4dione molecule." Eclética Química Journal 33, no. 1 (February 1, 2018): 71. http://dx.doi.org/10.26850/1678-4618eqj.v33.1.2008.p71-76.

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The structural and electronic properties of 1-(5-Hydroxymethyl - 4 –[ 5 – (5-oxo-5-piperidin- 1 -yl-penta- 1,3 -dienyl)-benzo [1,3] dioxol- 2 -yl]- tetrahydro -furan-2 -yl)-5-methy l-1Hpyrimidine-2,4dione (AHE) molecule have been investigated theoretically by performing density functional theory (DFT), and semi empirical molecular orbital calculations. The geometry of the molecule is optimized at the level of Austin Model 1 (AM1), and the electronic properties and relative energies of the molecules have been calculated by density functional theory in the ground state. The resultant dipole moment of the AHE molecule is about 2.6 and 2.3 Debyes by AM1 and DFT methods respectively, This property of AHE makes it an active molecule with its environment, that is AHE molecule may interacts with its environment strongly in solution.

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Sokhan, Vlad P., Andrew P. Jones, Flaviu S. Cipcigan, Jason Crain, and Glenn J. Martyna. "Signature properties of water: Their molecular electronic origins." Proceedings of the National Academy of Sciences 112, no. 20 (May 4, 2015): 6341–46. http://dx.doi.org/10.1073/pnas.1418982112.

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Water challenges our fundamental understanding of emergent materials properties from a molecular perspective. It exhibits a uniquely rich phenomenology including dramatic variations in behavior over the wide temperature range of the liquid into water’s crystalline phases and amorphous states. We show that many-body responses arising from water’s electronic structure are essential mechanisms harnessed by the molecule to encode for the distinguishing features of its condensed states. We treat the complete set of these many-body responses nonperturbatively within a coarse-grained electronic structure derived exclusively from single-molecule properties. Such a “strong coupling” approach generates interaction terms of all symmetries to all orders, thereby enabling unique transferability to diverse local environments such as those encountered along the coexistence curve. The symmetries of local motifs that can potentially emerge are not known a priori. Consequently, electronic responses unfiltered by artificial truncation are then required to embody the terms that tip the balance to the correct set of structures. Therefore, our fully responsive molecular model produces, a simple, accurate, and intuitive picture of water’s complexity and its molecular origin, predicting water’s signature physical properties from ice, through liquid–vapor coexistence, to the critical point.

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Tharammal, Rafsa Koyadeen, Anand Kumar, A. R. Abdul Rajak, and Vilas Haridas Gaidhane. "Theoretical Investigation of Design Methodology, Optimized Molecular Geometries, and Electronic Properties of Benzene-Based Single Molecular Switch with Metal Nanoelectrodes." Journal of Nanomaterials 2020 (September 1, 2020): 1–15. http://dx.doi.org/10.1155/2020/6260735.

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Understanding the electronic properties at the single molecular level is the first step in designing functional electronic devices using individual molecules. This paper proposes a simulation methodology for the design of a single molecular switch. A single molecular switch has two stable states that possess different chemical configurations. The methodology is implemented for 1,4-benzene dithiol (BDT) molecule with gold, silver, platinum, and palladium metal nanoelectrodes. The electronic properties of the designed metal-molecule-metal sandwich structure have been investigated using density functional theory (DFT) and Hartree-Fock (HF) method. It has been perceived that the DFT and HF values are slightly different as HF calculation does not include an electron-electron interaction term. Computation of the switching ratio gives the insight that BDT with gold has a high switching ratio of 0.88 compared with other three metal nanoelectrodes. Further, calculations of quantum chemical descriptors, analysis of the density of states (DOS) spectrum, and frontier molecular orbitals for both the stable states (i.e., ON and OFF state geometries) have been carried out. Exploring the band gap, ionization potential, and potential energy of two stable states reveals that the ON state molecule shows slightly higher conductivity and better stability than the OFF state molecule for every chosen electrode in this work. The proposed methodology for the single molecular switch design suggests an eclectic promise for the application of these new materials in novel single molecular nanodevices.

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Gao, W., M. Zhao, and Q. Jiang. "Electronic properties of single-molecule junction: Effect of the molecular distortion." Applied Surface Science 255, no. 22 (August 2009): 9259–63. http://dx.doi.org/10.1016/j.apsusc.2009.07.013.

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23

Endres, R. G., C. Y. Fong, L. H. Yang, G. Witte, and Ch Wöll. "Structural and electronic properties of pentacene molecule and molecular pentacene solid." Computational Materials Science 29, no. 3 (March 2004): 362–70. http://dx.doi.org/10.1016/j.commatsci.2003.09.006.

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24

Kumar, Ranjan, and Anita Rani. "Structure and electronic properties of Hn@C20 molecule." Physica B: Condensed Matter 406, no. 5 (March 2011): 1173–77. http://dx.doi.org/10.1016/j.physb.2010.12.076.

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Aiba, Akira, Madoka Iwane, Shintaro Fujii, and Manabu Kiguchi. "Electronic Properties of Single Atom and Molecule Junctions." ChemElectroChem 5, no. 18 (September 12, 2018): 2508–17. http://dx.doi.org/10.1002/celc.201800787.

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Aiba, Akira, Madoka Iwane, Shintaro Fujii, and Manabu Kiguchi. "Electronic Properties of Single‐Atom and ‐Molecule Junctions." ChemElectroChem 5, no. 18 (September 12, 2018): 2507. http://dx.doi.org/10.1002/celc.201801039.

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Lima, Matheus P., R. H. Miwa, and A. Fazzio. "The role played by the molecular geometry on the electronic transport through nanometric organic films." Physical Chemistry Chemical Physics 21, no. 44 (2019): 24584–91. http://dx.doi.org/10.1039/c9cp04304g.

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The electronic transport properties in molecular heterojunctions are intimately connected with the molecular conformation between the electrodes, and the electronic structure of the molecule/electrode interface.

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Ewen, Pascal R., Jan Sanning, Tobias Koch, Nikos L. Doltsinis, Cristian A. Strassert, and Daniel Wegner. "Spectroscopic mapping and selective electronic tuning of molecular orbitals in phosphorescent organometallic complexes – a new strategy for OLED materials." Beilstein Journal of Nanotechnology 5 (November 26, 2014): 2248–58. http://dx.doi.org/10.3762/bjnano.5.234.

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The improvement of molecular electronic devices such as organic light-emitting diodes requires fundamental knowledge about the structural and electronic properties of the employed molecules as well as their interactions with neighboring molecules or interfaces. We show that highly resolved scanning tunneling microscopy (STM) and spectroscopy (STS) are powerful tools to correlate the electronic properties of phosphorescent complexes (i.e., triplet emitters) with their molecular structure as well as the local environment around a single molecule. We used spectroscopic mapping to visualize several occupied and unoccupied molecular frontier orbitals of Pt(II) complexes adsorbed on Au(111). The analysis showed that the molecules exhibit a peculiar localized strong hybridization that leads to partial depopulation of a dz² orbital, while the ligand orbitals are almost unchanged. We further found that substitution of functional groups at well-defined positions can alter specific molecular orbitals without influencing the others. The results open a path toward the tailored design of electronic and optical properties of triplet emitters by smart ligand substitution, which may improve the performance of future OLED devices.

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Bhatta, Ram S., and Mesfin Tsige. "Structural Dependence of Electronic Properties in A-A-D-A-A-Type Organic Solar Cell Material." International Journal of Photoenergy 2015 (2015): 1–7. http://dx.doi.org/10.1155/2015/708048.

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Small conjugated molecules (SCMs) are promising candidates for organic photovoltaic (OPV) devices because of their structural simplicity, well control over synthetic reproducibility, and low purification cost. However, industrial development of SCM-based OPV devices requires improving their performance, which in turn relies on the fundamental understanding of structural dependence of electronic properties of SCMs. Herein, we report the structural and electronic properties of the BCNDTS molecule as a model system for acceptor-acceptor-donor-acceptor-acceptor (A-A-D-A-A) type SCMs, using density functional theory (DFT) and time-dependent DFT methods. Systematic calculations of two-dimensional potential energy surfaces, molecular electrostatic potential surfaces, ground state frontier molecular orbital energies, and the vertical excitation energies are performed. We found that the lowest energy conformation of the BCNDTS molecule is planar. The planar conformation favors the lowest ground state and the excited state energies as well as the strongest oscillator strength. The present results suggest that SCMs containing central dithienosilole cores connected with 2,1,3-benzothiadiazole groups have potential to be an efficient electron donor for OPV devices.

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Shi, De-heng, Hui Liu, Jin-feng Sun, Zun-lue Zhu, and Yu-fang Liu. "Spectroscopic and molecular properties of 14 selected electronic states of Si2 molecule." Journal of Quantitative Spectroscopy and Radiative Transfer 112, no. 16 (November 2011): 2567–83. http://dx.doi.org/10.1016/j.jqsrt.2011.07.007.

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31

ÇALIŞIR, EMİNE DENİZ, and ŞAKİR ERKOÇ. "STRUCTURAL, ELECTRONIC AND QSAR PROPERTIES OF THE CYFLUTHRIN MOLECULE: A THEORETICAL AM1 AND PM3 TREATMENT." International Journal of Modern Physics C 17, no. 10 (October 2006): 1391–402. http://dx.doi.org/10.1142/s0129183106009904.

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Cyfluthrin is a synthetic cyano-containing pyrethroid insecticide that has both contact and stomach poison action. It is a nonsystemic chemical used to control cutworms, ants, silverfish, cockroaches, mosquitoes, tobacco budworm and many others. Its primary agricultural uses have been for control of chewing and sucking insects on crops such as cotton, turf, ornamentals, hops, cereal, corn, deciduous fruit, peanuts, potatoes, and other vegetables. Cyfluthrin is also used in public health situations and for structural pest control. The structural, vibrational, electronic and QSAR properties of the cyfluthrin molecule in gas phase have been investigated theoretically by performing molecular mechanics method by using MM+ force field, and semi-empirical molecular orbital AM1 and PM3 calculations. The geometry of the molecule has been optimized, infrared spectrum (vibrational modes and intensities) and the electronic properties of the molecule have been calculated in its ground state. According to PM3 calculation, heat of formation of cyfluthrin molecule is about -48.58 kcal/mol (exothermic), which shows that this molecule thermodynamically be stable. The HOMO energy level for this molecule is found to be -9.701 eV and the LUMO energy level is -0.660 eV giving rise to a gap of 9.041 eV, which also indicates that cyfluthrin is thermodynamically stable.

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Masuda, S., Y. Koide, M. Aoki, and Y. Morikawa. "Local Electronic Properties Induced at the Molecule−Metal Interface." Journal of Physical Chemistry C 111, no. 32 (July 25, 2007): 11747–50. http://dx.doi.org/10.1021/jp074101w.

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33

Valencia-Maturana, Ramon, and Chun-Wei Pao. "Electronic and carrier transport properties of small molecule donors." Coupled systems mechanics 6, no. 1 (March 25, 2017): 75–96. http://dx.doi.org/10.12989/csm.2017.6.1.075.

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Valencia-Maturana, Ramon, and Chun-Wei Pao. "Electronic and carrier transport properties of small molecule donors." Multiscale and Multiphysics Mechanics 1, no. 4 (October 25, 2016): 305–26. http://dx.doi.org/10.12989/mmm.2016.1.4.305.

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Mutier, Mohammed N., and Lafy F. Al-Badry. "Electronic and thermoelectric properties of a single pyrene molecule." Chinese Journal of Physics 63 (February 2020): 365–74. http://dx.doi.org/10.1016/j.cjph.2019.11.025.

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Östling, Daniel, and A. Rosén. "Electronic properties of the C60 molecule doped with potassium." Chemical Physics Letters 202, no. 5 (January 1993): 389–93. http://dx.doi.org/10.1016/0009-2614(93)90058-9.

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37

McMahon, Jim. "AFM Measurements of DNA Molecule Electron Transport Properties." Microscopy Today 18, no. 5 (August 24, 2010): 20–23. http://dx.doi.org/10.1017/s1551929510000830.

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Deoxyribonucleic acid (DNA) has been considered as a possibility for molecular electronics. Because DNA is able to recognize other molecules—other strands of DNA—and because it binds together with similar DNA strands in a very unique way, scientists have suggested the possibility of using DNA as an electronic circuit without having to build in any other circuitry. The DNA would bind with other similar DNA strands that it recognizes and then use the connecting properties of the DNA to create a self-assembled biological wire for electrical conduction. Until recently, uncertainty existed about whether DNA could conduct at all, and if it could, how well it could conduct. Scientific speculations ranged from DNA being a superconductor to a complete insulator. Recent research, however, by Dr. Sidney R. Cohen in collaboration with Dr. Ron Naaman and Dr. Claude Nogues of the Weizmann Institute of Science, Scanned Probe Microscopy Unit, in Rehovot, Israel, aided by the enabling technologies of ultra-high-resolution microscopy and negative-stiffness vibration isolation, has shed new light on the electrical transport properties of DNA, focusing on the capacity of single molecules of DNA to transport current along individual strands.

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Siddiqui, Shamoon Ahmad, Tabish Rasheed, Mohd Faisal, Anoop Kumar Pandey, and Sher Bahadar Khan. "Electronic Structure, Nonlinear Optical Properties, and Vibrational Analysis of Gemifloxacin by Density Functional Theory." Spectroscopy: An International Journal 27 (2012): 185–206. http://dx.doi.org/10.1155/2012/614710.

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The non-linear optical properties of gemifloxacin (C18H20FN5O4) have been examined using density functional theory (DFT). The molecular HOMO, LUMO composition, their respective energy gaps, MESP contours/surfaces have also been drawn to explain the activity of gemifloxacin. The equilibrium geometries and harmonic frequencies of title molecule was determined and analyzed at DFT/B3LYP level employing the 6-31G(d,p) basis set. The skeleton of both the optimized molecules is non-planar. In general, a good agreement between experimental and calculated normal modes of vibrations has been observed.

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39

Xiao, Hai Mei, and Li Chun Shi. "The Application Research of Single-Molecule Magnets and Molecular Spin Electronics Materials." Advanced Materials Research 485 (February 2012): 522–25. http://dx.doi.org/10.4028/www.scientific.net/amr.485.522.

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In the basic and applied research, the electronics and spin degrees of freedom is a very promising field of research and development over the past decade, spintronics from fundamental physics to technical devices already have a great deal of progress. This study made an overview of the synthesis, structure and properties of single molecular magnets and their applications in molecular spin combined with the latest research on this study sphere. Single molecular magnets are made of inner magnetic nuclei and peripheral organic molecule lamella, which can improve physical and chemical properties by means of adorn radical of organic ligand and exchange internal magnetic ions. And this paper also analyzes the molecular spin of the electron spin and charge electronic devices at the molecular level.

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40

Koslowski, Sebastian, Daniel Rosenblatt, Alexander Kabakchiev, Klaus Kuhnke, Klaus Kern, and Uta Schlickum. "Adsorption and electronic properties of pentacene on thin dielectric decoupling layers." Beilstein Journal of Nanotechnology 8 (July 6, 2017): 1388–95. http://dx.doi.org/10.3762/bjnano.8.140.

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With the increasing use of thin dielectric decoupling layers to study the electronic properties of organic molecules on metal surfaces, comparative studies are needed in order to generalize findings and formulate practical rules. In this paper we study the adsorption and electronic properties of pentacene deposited onto h-BN/Rh(111) and compare them with those of pentacene deposited onto KCl on various metal surfaces. When deposited onto KCl, the HOMO and LUMO energies of the pentacene molecules scale with the work functions of the combined KCl/metal surface. The magnitude of the variation between the respective KCl/metal systems indicates the degree of interaction of the frontier orbitals with the underlying metal. The results confirm that the so-called IDIS model developed by Willenbockel et al. applies not only to molecular layers on bare metal surfaces, but also to individual molecules on thin electronically decoupling layers. Depositing pentacene onto h-BN/Rh(111) results in significantly different adsorption characteristics, due to the topographic corrugation of the surface as well as the lateral electric fields it presents. These properties are reflected in the divergence from the aforementioned trend for the orbital energies of pentacene deposited onto h-BN/Rh(111), as well as in the different adsorption geometry. Thus, the highly desirable capacity of h-BN to trap molecules comes at the price of enhanced metal–molecule interaction, which decreases the HOMO–LUMO gap of the molecules. In spite of the enhanced interaction, the molecular orbitals are evident in scanning tunnelling spectroscopy (STS) and their shapes can be resolved by spectroscopic mapping.

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Gunjo, Yuki, Hajime Kamebuchi, Ryohei Tsuruta, Masaki Iwashita, Kana Takahashi, Riku Takeuchi, Kaname Kanai, et al. "Interface Structures and Electronic States of Epitaxial Tetraazanaphthacene on Single-Crystal Pentacene." Materials 14, no. 5 (February 26, 2021): 1088. http://dx.doi.org/10.3390/ma14051088.

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The structural and electronic properties of interfaces composed of donor and acceptor molecules play important roles in the development of organic opto-electronic devices. Epitaxial growth of organic semiconductor molecules offers a possibility to control the interfacial structures and to explore precise properties at the intermolecular contacts. 5,6,11,12-tetraazanaphthacene (TANC) is an acceptor molecule with a molecular structure similar to that of pentacene, a representative donor material, and thus, good compatibility with pentacene is expected. In this study, the physicochemical properties of the molecular interface between TANC and pentacene single crystal (PnSC) substrates were analyzed by atomic force microscopy, grazing-incidence X-ray diffraction (GIXD), and photoelectron spectroscopy. GIXD revealed that TANC molecules assemble into epitaxial overlayers of the (010) oriented crystallites by aligning an axis where the side edges of the molecules face each other along the [1¯10] direction of the PnSC. No apparent interface dipole was found, and the energy level offset between the highest occupied molecular orbitals of TANC and the PnSC was determined to be 1.75 eV, which led to a charge transfer gap width of 0.7 eV at the interface.

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Zhao, Zhen, and Zhi Li. "Structures, electronic properties and adsorption mechanisms of the O2Fe3N clusters." International Journal of Modern Physics B 33, no. 19 (July 30, 2019): 1950214. http://dx.doi.org/10.1142/s021797921950214x.

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The structures, adsorption mechanisms and electronic attributes of the O2Fe3N clusters are calculated at Perdew, Burke and Ernzerhof (PBE) functional. The results show that two O atoms prefer to be located at the Fe–Fe bridge site of Fe–N molecule which form the ground-state O2Fe3N cluster, respectively. It means that O2 molecule is dissociated by Fe3N molecule. Compared to the isomer (3)–(6), it indicates that an O2 molecule is preferentially adsorbed on the top site of Fe atom which is close to N atom of the Fe3N molecule in the vertical direction. The adsorptions of Fe3N with O2 are the exothermic before endothermic reaction. All the O2Fe3N clusters possess higher kinetic activity. The average spin magnetic moments of the O2Fe3N clusters are as follows: isomer (6) [Formula: see text] isomer (1) [Formula: see text] isomer (3) [Formula: see text] isomer (5) [Formula: see text] ground-state [Formula: see text] isomer (2) [Formula: see text] isomer (4). Compared to the external charge transfer of the O2Fe3N clusters, the transfer of electrons between 4s and 3d, 4p orbitals in the same atom is significantly higher.

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Matsuda, Kenji. "Photochromic diarylethene as an information processing unit: Magnetic and electric switching." Pure and Applied Chemistry 80, no. 3 (January 1, 2008): 555–61. http://dx.doi.org/10.1351/pac200880030555.

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Photochromic compounds reversibly change not only the absorption spectra but also their geometrical and electronic structures. This principle can be applied for the photoswitching of the physical properties of the molecular materials. In particular, photoswitching of the flow of information through the molecule is interesting because information processing using molecular devices is attracting interest in the molecular electronics field. The photoswitchings of the magnetic exchange interaction and the electrical conductance using photochromic diarylethene are described.

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Zhang, Xin Wei, Cun Li, and Jun Qi Xu. "Study on the Second-Order Nonlinear Optical Properties of [6]Helicenes with Chromophores." Applied Mechanics and Materials 303-306 (February 2013): 2563–66. http://dx.doi.org/10.4028/www.scientific.net/amm.303-306.2563.

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A series of chiral [6]helicenes have been designed using the molecular engineering of organic nonlinear optical materials. The geometries of [6]helicenes 1, 2, 3, 4,5 are optimized using density functional theory (DFT-B3LYP) method at the 6-31g (d, p) basis set level. Based on the obtained stable molecular configuration, we adopt the TDHT/PM3 method and time-dependent density-functional theory (TD-DFT) to calculate the nonlinear optical (NLO) properties and electronic spectra of these molecules. Results show that the static hyperpolarizability βµ alternates between positive value and negative value, whereas it remains positive for the molecues 2 and 3 which have medium magnitudes βµ, 3.4×10-30esu and 9.6×10-30esu respectively. In molecule 5, there exists two competitive charge transfers that reduce the hyperpolarizability β.

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SHEN, HAIJUN. "TENSILE PROPERTIES AND ELECTRONIC STRUCTURES OF C240 NANOTUBE AND 4C60 FULLERENE POLYMERS." International Journal of Nanoscience 05, no. 01 (February 2006): 99–107. http://dx.doi.org/10.1142/s0219581x06004073.

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The classical MD (Molecular Dynamics) method was used to simulate the tension of three kinds of C 240 isomers, i.e., C 240 nanotube, chain-like 4C 60 fullerene polymer and peanut-like 4C 60 fullerene polymer. Then, the semi-empirical PM3 method was used to calculate their electronic structures under tension. Lastly, according to the calculated results, their differences in tensile mechanical properties, as well as the change of their FMO (Frontier Molecular Orbital) energy during tension, were discussed. It is shown that: (1) the load-support capability of the C 240 molecules has the order of C 240 nanotube > peanut-like 4C 60 polymer > linear 4C 60 polymer, but their deformation-support capability has the contrary order, (2) of the C 240 isomers, the C 240 nanotube has the best chemical stability, and the chain-like 4C 240 molecule has the worst one, and (3) the deformed C 240 isomers have narrower energy-gap between their LUMO and HOMO, and higher chemical activity.

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RAMAN, KARTHIK V., NICOLAE ATODIRESEI, and JAGADEESH S. MOODERA. "TAILORING FERROMAGNET–MOLECULE INTERFACES: TOWARDS MOLECULAR SPINTRONICS." SPIN 04, no. 02 (June 2014): 1440014. http://dx.doi.org/10.1142/s2010324714400141.

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Understanding the interaction of organic molecules adsorbed on magnetic surfaces has shown considerable progress in recent years. The creation of hybridized interface between carbon-based aromatic molecule and the magnetic surface is observed to give rise to new interface states with unique electronic and magnetic character. This study has opened up a molecular-design initiative to tailor the spin dependent electronic and magnetic functionalities of the hybrid interface. The purpose of this article is to provide a fundamental understanding of the spin-chemistry and spin-physics associated with the formation of such ferromagnet-molecule hybrid interfaces. We also discuss the recent progress in this field using state-of-the-art experiments and theoretical calculations with focus on the magnetic properties of the molecule and the magnetic surface. The study reveals several interesting interface phenomena: formation of induced molecular moment and exchange coupling with the magnetic surface, and molecular spin-filters. It also demonstrates significant changes in the magnetic anisotropy and inter-atomic magnetic exchange coupling of the magnetic surface. These studies open the possibilities of exploring new molecular functionalities toward further research in the subfield of interface-assisted molecular spintronics.

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MAITI, SANTANU K. "QUANTUM TRANSPORT THROUGH SINGLE PHENALENYL MOLECULE: EFFECT OF INTERFACE STRUCTURE." International Journal of Nanoscience 06, no. 06 (December 2007): 415–22. http://dx.doi.org/10.1142/s0219581x07004985.

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The electronic transport characteristics through a single phenalenyl molecule sandwiched between two metallic electrodes are investigated by using Green's function technique. A parametric approach, based on the tight-binding model, is used to study the transport characteristics through such molecular bridge system. The electronic transport properties are significantly influenced by (a) the molecule-to-electrodes interface structure and (b) the molecule-to-electrodes coupling strength.

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Kushmerick, James G., David L. Allara, Thomas E. Mallouk, and Theresa S. Mayer. "Electrical and Spectroscopic Characterization of Molecular Junctions." MRS Bulletin 29, no. 6 (June 2004): 396–402. http://dx.doi.org/10.1557/mrs2004.122.

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AbstractThe design of future molecular electronic devices requires a firm understanding of the conduction mechanisms that determine their electrical characteristics. Progress toward this goal has been hindered by complications in controlling the exact configuration and makeup of fabricated molecular junctions, thus limiting the availability of quantitative experimental data for developing cohesive theories to model and predict molecular transport. This article summarizes recent research aimed at developing well-controlled systems for comparing molecular conduction and vibrational spectra using crossed-wire and in-wire metal–molecule–metal junctions. Systematic variations in molecular structure and metal–molecule contacts show strong quantitative agreement in device properties, while spectroscopic data provide evidence that the properties are due to the molecular junction. Further investigations using these and other molecular junction test beds will provide the needed experimental data to advance fundamental understanding of molecular transport and facilitate future molecular electronics applications.

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XIA, CAI-JUAN, DE-HUA ZHANG, and YING-TANG ZHANG. "THE ELECTRONIC TRANSPORT PROPERTIES IN NAPHTHOPYRAN-BASED OPTICAL MOLECULAR SWITCH WITH CARBON NANOTUBE ELECTRODES." Journal of Theoretical and Computational Chemistry 12, no. 07 (November 2013): 1350068. http://dx.doi.org/10.1142/s0219633613500685.

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By applying nonequilibrium Green's function (NEGF) formalism combined first-principles density functional theory (DFT), we investigate the electronic transport properties of optical molecular switch based on the naphthopyran molecule with two different single-walled carbon nanotube (SWCNT) electrodes. The molecule that comprises the switch can convert between the closed and open forms upon photoexcitation. Theoretical results show that these two forms exhibit very different conductance properties both in armchair and zigzag junction, which can realize the on and off states of the molecular switch. Meantime, the chirality of the SWCNT electrodes strongly affects the switching characteristics of the molecular junctions. The maximum value of on–off ratio can reach 292 at 1.6 V for the switch with zigzag SWCNT electrodes.

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Mottaghi, A., and Ali R. Ashrafi. "Topological edge properties of C60+12 n fullerenes." Beilstein Journal of Nanotechnology 4 (June 26, 2013): 400–405. http://dx.doi.org/10.3762/bjnano.4.47.

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A molecular graph M is a simple graph in which atoms and chemical bonds are the vertices and edges of M, respectively. The molecular graph M is called a fullerene graph, if M is the molecular graph of a fullerene molecule. It is well-known that such molecules exist for even integers n ≥ 24 or n = 20. The aim of this paper is to investigate the topological properties of a class of fullerene molecules containing 60 + 12n carbon atoms.

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Journal articles on the topic 'Molecule electronic properties'

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