Dissertations / Theses: 'ENERGY MOLECULES'

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Hoffmeyer, Ruth Ellen. "High-energy electron scattering from molecules." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35471.pdf.

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Rawi, Zaid. "Rotational energy transfer in polyatomic molecules." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390073.

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Pounds, Andrew J. "A generalized discrete dynamical search method for locating minimum energy molecular geometries." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/27144.

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Ball, Christopher D. "Rotational energy transfer in low temperature molecules /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487951214940079.

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Rempe, Susan Lynne Beamis. "Potential energy surfaces for vibrating hexatomic molecules /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/8536.

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Shi, Yuanyuan. "Materials and molecules for pollution free clean energy." Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/664725.

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La combustió dels combustibles fòssils ha causat problemes mediambientals i energètics a nivell mundial, la qual cosa influeix en la salut i les activitats humanes. Amb la motivació de contribuir per resoldre aquests problemes, hem realitzat una sèrie de recerques per explorar materials i molècules per a la generació d'energia lliure de contaminació, com és l'energia solar convertida en hidrogen que proposa aquesta tesi. Hem analitzat estadísticament les partícules contaminants en l'aire, partícules de PM2.5, les quals indiquen que els agregats de sutge rics en carboni mostren una adhesividad i agregació molt altes. Més del 50% de les partícules PM2.5 interactuen fortament amb el substrat generant una capa molt prima (<10 nm) la qual és molt estable (fins i tot sota estrès mecànic) i que està composta de metalls alcalins, hidrogen i grups CH. Després de l'estudi sobre partícules contaminants en l'aire, ens hem centrat en l'estudi de dispositius de divisió d'aigua mitjançant radiació solar per explorar la generació d'hidrogen a gran escala. En aquesta tesi, ens hem centrat principalment en la recerca de materials i molècules per a divisors de molècules d'aigua fotoelectroquímics (PEC) i fotovoltaic-electrolítics (PV-EC). Els nostres resultats mostren que en els dispositius PEC, poden dipositar-se en la superfície dels foto-ànodes de silici pel·lícules primes metàl·liques de coure i níquel, podent formar CuO i NiOX respectivament. Tots dos materials actuen com a catalitzadors molt actius per a la reacció d'oxidació d'aigua i alhora com una capa protectora de la corrosió per a superfície de silici. D'altra banda, els dispositius PV-EC, pels quals hem utilitzat un ànode basat en molècules catalizadoras de Ruteni, s'ha integrat amb cèl·lules solars d'unió triple. Aquests dispositius han aconseguit una eficiència màxima de conversió energia solar-hidrogen del 21,2% a pH neutre i just per sota de la il·luminació solar sense cap polarització externa. Aquests resultats contribueixen a la generació d'hidrogen per conversió solar a gran escala.
La combustión de los combustibles fósiles ha causado problemas medioambientales y energéticos a nivel mundial, lo que influye en la salud y las actividades humanas. Con la motivación de contribuir para resolver estos problemas, hemos realizado una serie de investigaciones para explorar materiales y moléculas para la generación de energía libre de contaminación, como es la energía solar convertida en hidrógeno que propone esta tesis. Hemos analizado estadísticamente las partículas contaminantes en el aire, partículas de PM2.5, las cuales indican que los agregados de hollín ricos en carbono muestran una adhesividad y agregación muy altas. Más del 50% de las partículas PM2.5 interactúan fuertemente con el sustrato a través de una capa muy delgada (<10 nm) de trazas oscura la cual es muy estable incluso bajo estrés mecánico y está compuesta de metales alcalinos, hidrógeno y grupos CH. Después del estudio sobre partículas contaminantes en el aire, nos hemos centrado en el estudio de dispositivos de división de agua mediante radiación solar para explorar la generación de hidrógeno a gran escala. En esta tesis, nos hemos centrado principalmente en la investigación de materiales y moléculas para divisores de moléculas de agua fotoelectroquímicos (PEC) y fotovoltaico-electrolíticos (PV-EC). Nuestros resultados muestran que en los dispositivos PEC, pueden depositarse en la superficie de los foto-ánodos de silicio películas delgadas metálicas de cobre y níquel, pudiendo formar CuO y NiOX respectivamente. Ambos materiales actúan como catalizadores muy activos para la reacción de oxidación de agua y a la vez como una capa protectora de la corrosión para superficie de silicio. Por otro lado, los dispositivos PV-EC, para los que se usó un ánodo basado en moléculas catalizadoras de Rutenio, se ha integrado con células solares de unión triple comerciales. Estos dispositivos han logrado una eficiencia máxima de conversión energía solar-hidrógeno del 21,2% a pH neutro y justo por debajo de la iluminación solar sin ninguna polarización externa. Estos resultados allanan el camino para la generación de hidrógeno por conversión solar a gran escala.
The combustion of the fossil fuels has caused the global environment and energy problems, which influences human health and activities. With the motivation to make our contributions to solving these problems, we have performed a series of investigations to explore materials and molecules for pollution free clean energy, which is solar energy converted hydrogen in this thesis. We have statistically analyzed the airborne pollutant particles, PM2.5 particles, which indicates that the carbon-rich fluffy soot aggregates always show very high adhesiveness and aggregation. And more than 50% PM2.5 particles strongly interact with the substrate through a ultra-thin (< 10 nm) dark trace layer, which is very stable even under mechanical stress and it is consisted of alkali metals, hydrogen and CH groups. After the study about airborne pollutant particles, we have moved to the study of solar-driven water splitting devices for exploring the large-scale generation of hydrogen. In this thesis, we have mainly focused on the investigation of the materials and molecules for photoelectrochemical (PEC) and photovoltaic-electrolysis (PV-EC) water splitting devices. Our results show that in the PEC water splitting devices, copper and nickel metallic thin films can be deposited on the surface of silicon photoanodes, which can form CuO and NiOX respectively and then serve as very active catalysts for water oxidation reaction and a protecting layer for silicon surface from corrosion. And in PV-EC water splitting devices, the ruthenium molecular catalysts based anode has been used for the electrolyzer, which has been integrated with commercially available triple junction solar cells. This integrated PV-EC device achieves the highest solar-to-hydrogen efficiency of 21.2 % at neutral pH and just under solar illumination without any external bias. These results pave the way for the generation of large-scale solar converted hydrogen.

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Wickham-Jones, C. T. "Studies of vibrational energy transfer of small molecules." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371569.

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Lyons, Benjamin Paul. "Energy transfer to dopant molecules in polyfluorene films." Thesis, Durham University, 2005. http://etheses.dur.ac.uk/2722/.

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Polyfluorene is a promising material for applications such as polymeric light-emitting diodes. Upon optical or electrical excitation it exhibits efficient blue fluorescence and is easily made into thin films by spin-coating from solution. Incorporating suitable dopant molecules in these films changes the emission colour. The energy transfer processes taking place have been investigated here by steady-state and time resolved fluorescence measurements. To assist in the analysis of these measurements, the optical constants of polyfluorene were found by ellipsometry. Both unaligned and aligned films exhibit uniaxial anisotropy. Unaligned films have their optical axis normal to the film surface and are optically negative. Aligned films have their optical axis oriented in plane, parallel to the rubbing direction and are optically positive. In aligned films, light polarized in the alignment direction experiences absorption twice as high as light incident on unaligned films. Temperature dependent steady-state measurements were made on polyfluorene films doped with tetraphenyl poiphyrin. Energy transfer in such systems is usually described in terms of Forster transfer but it is shown here that exciton migration must also occur. A new model is developed to include this process. Diffusion lengths of 11 +1- 2 nm at low temperature and 20 +/- 2 nm at room temperature are found. Energy transfer was also investigated by fluorescence polarization anisotropy. It is shown that even at low temperature; excitons migrate far enough to depolarize the fluorescence. However, the emission is not completely depolarized and it is suggested that some excitons are trapped immediately after excitation. Polarized luminescence from dicyanomethylene in aligned polyfluorene films is observed. These molecules align themselves at least partially with the polymer chains. Although the polarization ratio not sufficient for use in a device, this is a viable method of achieving polarized fluorescence with a range of colours.

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Hock, Kai Meng. "Low energy electron scattering from molecules on surfaces." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240119.

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Barnard, John Cameron. "Low energy electron scattering by ordered adsorbed molecules." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321430.

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Kim, Kilyoung. "Super Collision Energy Transfer Studies in Single Collisions Between Vibrationally Hot Benzene Like Molecules and Ground State Bath Molecules: The Effect of Physical Properties of Donor and Bath Molecules on Super Collision Energy Transfer." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2497.

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This research is focused on single-collision energy transfer events between highly vibrationally excited benzene-like donor molecules and small bath molecules, CO2 and N2O in the vibrational ground level. Measuring how much energy is transferred from donors to bath molecules was accomplished by probing bath molecules scattered into specific-rotational states using a tunable Δv=0.0003 cm-1 solid state diode laser. The normalized energy transfer probability distribution function, P(E,E'), determined from energy gain information, is very useful in comparing collisional energy transfer efficiency between various collision systems. P(E,E') is also used to investigate the effects of donor and bath physical properties on collisional energy transfer. The first chapter details the C6H5F–CO2 system, which is the basis of a study on the effect of donor fluorination on strong collision energy transfer. The second chapter is about all fluorobenzene–CO2 systems, which investigates the effect of excess vibrational excitation energy of donors on supercollision energy transfer efficiency as well as donor fluorination effect. The third chapter focuses on how the physical properties of bath molecules affect supercollision energy transfer by measuring state-specific energy gain of N2O scattered into 0000, J=59−75. Instead of CO2, N2O was used as a bath molecule with a pyrazine donor to compare energy gain results of bath molecules with somewhat different physical properties. N2O and CO2 are isoelectronic and have similar mass, but N2O has a small dipole moment. Comparison of P(E,E') obtained from pyrazine–CO2, –N2O, –DCl, and –H2O systems helps to elucidate the effect of the bath physical properties on supercollision energy transfer efficiency. The last chapter is dedicated to the extension of the measurement range of N2O energy gain to the mid J states (J=37–75). In this chapter I discuss reliability of P(E,E') obtained from only high J tail as well as the correction of overall energy transfer rate constant.

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Fang, Chunchang. "Product energy partitioning and collision energy dependence in reactions of copper with halogen molecules and of group IVA elements with oxidizing molecules /." The Ohio State University, 1989. http://rave.ohiolink.edu/etdc/view?acc_num=osu148767164005507.

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Boyle, Mark L. "Energy absorption and redistribution dynamics in isolated C60 molecules." [S.l. : s.n.], 2005. http://www.diss.fu-berlin.de/2005/187/index.html.

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Jensen, Erik Troels. "Low energy electron scattering studies of molecules at surfaces." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334137.

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Howson, Joanna M. M. "Obtaining potential energy surfaces of Van der Waals molecules." Thesis, Durham University, 1999. http://etheses.dur.ac.uk/4488/.

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Two different methods were used to obtain a potential energy surface for the Arco molecule. One involved choosing a functional form for the repulsion and dispersion energies whose parameters were determined by a fit to experimental data. A physically justified potential that agreed with experiment could not be obtained. The other method was based on calculating ab initio interaction energies at different configurations of the molecule and interpolating between them. The resulting surface was scaled in the energy and the co-ordinates. Improved agreement was achieved for most observed bound states. Errors in the surface may have been due to an inadequate density of ab initio energies. So, how the molecular configurations chosen for interaction energy calculations affected the potential obtained was investigated. Both the co-ordinate system and the interpolation scheme also significantly affected the quality of surface obtained. The best compromise between accuracy and number of configurations, was points distributed on a regular grid in elliptic co-ordinates with Gauss-Legendre quadrature points in the angular co-ordinate. This information was employed to obtain a potential energy surface for the weakly bound HeOCS molecule which was in close agreement with experiment. A co-ordinate and energy scaling, guided by experiment, was applied to the ab initio surface. Only three scaling parameters were required due to the high quality of the initial surface.

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Lücken, Jana. "Transformations of Energy-Related Small Molecules at Dinuclear Complexes." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2020. http://hdl.handle.net/21.11130/00-1735-0000-0005-1563-4.

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Mort, Steven P. "Potential energy surfaces for SiHâ†2+." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240482.

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Buades, Martín Ana Begoña. "Metallacarboranes: Synthesis of Boron-Heteroatom Derivatives and Applications in Energy and Magnetism." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671975.

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Aquesta tesi consta de sis capítols. El primer introdueix al lector al món de la química del bor des de la síntesi i caracterització del primer compost en 1912. El capítol 2 revela el poder de combinar la química teòrica amb l’experimental per a entendre la naturalesa dels enllaços B-C amb l’ús de bromur de tritil en lloc dels comunament usats, catalitzadors de pal·ladi o derivats iodats per a obtenir derivats B-C de COSANE en segons. L’objectiu del capítol 3 és la síntesi i caracterització espectroscòpica i electroquímica dels derivats de COSANE i/o FESANE amb bipiridina per a estudiar el nombre d’electrons capaços d’acceptar de manera reversible per aquestes noves estructures. D’una banda, el capítol 4 presenta els derivats clorats de COSANE amb major nombre de clors sintetitzats fins avui. L’estudi aporta la síntesi i caracterització espectroscòpica i electroquímica per a conèixer les seves possibles aplicacions electroquímiques. D’altra banda, el capítol 5 s’enfoca a estudiar el comportament de dits derivats com a catalitzadors redox per a electròlisis d’aigua. La recerca es basa a aconseguir funcionalitzar barres de grafit amb els derivats clorats de COSANE i estudiar tant el seu poder electrocatalitzador com la seva estabilitat davant els processos electroquímics. Finalment, la recerca descrita en el capítol 6 està enfocada a obtenir un cristall de [NMe4]FESAN que pugui ser resolt per difracció de raigs X per a estudiar mitjançant estudi teòrics les seves propietats magnètiques, per poder mesurar experimentalment el seu temps de relaxació i valora les seves aplicacions com qubit per a ordinadors quàntics.
Esta tesis consta de seis capítulos. El primero introduce al lector al mundo de la química del boro desde la síntesis y caracterización del primer compuesto en 1912. El capítulo 2 revela el poder de combinar la química teórica con la experimental para entender la naturaleza de los enlaces B-C con el uso de bromuro de tritilo en lugar de los comúnmente usados, catalizadores de paladio o derivados iodados para obtener derivados B-C de COSANE en segundos. El objetivo del capítulo 3 es la síntesis y caracterización espectroscópica y electroquímica de los derivados de COSANE y/o FESANE con bipiridina para estudiar el número de electrones capaces de aceptar de forma reversible por estas nuevas estructuras. Por un lado, el capítulo 4 presenta los derivados clorados de COSANE con mayor número de cloros sintetizados hasta la fecha. El estudio aporta la síntesis y caracterización espectroscópica y electroquímica para conocer sus posibles aplicaciones electroquímicas. Por otro lado, el capítulo 5 se enfoca en estudiar el comportamiento de dichos derivados como catalizadores redox para electrolisis de agua. La investigación se basa en conseguir funcionalizar barras de grafito con los derivados clorados de COSANE y estudiar tanto su poder electro catalizador como su estabilidad ante los procesos electroquímicos. Finalmente, la investigación descrita en el capítulo 6 está enfocado a obtener un cristal de [NMe4]FESAN que pueda ser resuelto por difracción de rayos X para estudiar mediante estudio teóricos sus propiedades magnéticas, para poder medir experimentalmente su tiempo de relajación y valora sus aplicaciones como qubit para ordenadores cuánticos.
This thesis is divided into six chapters. First one introduces the reader to the chemistry world, since the synthesis and characterization of the first boron compound in 1912. Chapter 2 unveils the power to combine theoretical with experimental chemistry to understand the nature of the B-C bond formation using trytilbromide instead of the usual palladium catalyst or iodinate derivatives to obtain B-C derivatives of COSAN in seconds. The target of the research explained on Chapter 3 is the synthesis, spectroscopic and electrochemical characterization of bipyridine derivatives of COSAN and/or FESAN to study the number of electrons able to accept in a reversible way for every product. On the one hand, Chapter 4 present the highest chlorinated derivatives of COSAN synthesized since the date. The study provides the spectroscopic and electrochemical characterization to unveil their possible electrochemical application. On the other hand, Chapter 5 study the behaviour of these derivatives as electrocatalysts for water electrolysis. The research was focus on functionalizing graphite rods with chloro derivatives of COSAN and study their catalytic power together with their electrochemical stability to demonstrate the high potential of these compounds for water oxidation processes. Finally, the research described in Chapter 6 takes advantage of the unpair electron of FESAN to study its properties as Single-Molecule Magnet (SMM). The study was focus on achieving a monocrystal of [NMe4]FESAN able to be resolved by X-ray diffraction to study the magnetic properties of the molecule by theoretical calculations and the study of the relaxation time of the molecule needed to assess its applications as a qubit for quantum computing.
Universitat Autònoma de Barcelona. Programa de Doctorat en Química

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Gillan, Charles James. "Theory of low energy scattering of electrons by diatomic molecules." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356873.

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Mordaunt, David H. "Photodissociation dynamics of small atmospherically important molecules." Thesis, University of Bristol, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388430.

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Orro, Graña Adolfo. "Examination of the role of binding site water molecules in molecular recognition." Thesis, SciLifeLab Stockholm, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-200164.

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A set of algorithms were designed, implemented and evaluated in order to, first, identifyclusters of conserved waters in binding pockets, i.e. hydration sites. Then, their contributionto the free energy of binding in a ligand-protein association was quantified by calculatingtheir enthalpy and entropy. The information obtained by using these algorithms couldcontribute to the development of new drugs by generating new ligands that target specifichigh-energy, unfavorable waters. Evaluation tests show that our algorithms can indeedprovide relevant data about how hydration sites influence ligand-protein binding.

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Huang, Yiye. "Determining Analytical Potential Energy Functions of Diatomic Molecules by Direct Fitting." Thesis, University of Waterloo, 2001. http://hdl.handle.net/10012/1284.

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The fully quantum mechanical 'direct-potential-fit' (DPF) method has become increasingly widely used in the reduction of diatomic spectra. The central problem of this method is the representation of the potential energy and Born-Oppenheimer breakdown (BOB) correction functions. There are a number of problems associated with the existing method and potential forms. This thesis delineates these problems and finds solutions to some of them. In particular, it is shown that use of a different expansion variable and a new treatment of some of the expansions resolves most of the problems. These techniques have been successfully tested on the ground electronic states of the coinage metal hydrides and the Rb2 molecule. To address the problem of representing 'barrier' potential curves, a flexible new functional form, the 'double-exponential long-range' (DELR) potential function, is introduced and applied to the B barrier state of Li2. In addition, the Lambda-doubling level splitting which occurs for singlet Pi electronic states has been taken into account by extending the effective Schrodinger equation. The computer program DSPotFit developed in our laboratory for performing DPF analyses has been extended to incorporate the ability to fit the analytical potential energy functions to tunneling predissociation line widths for quasibound levels. Finally, an attempt is made to investigate whether there exists a hump in the ground state rotationless potential curve of beryllium hydride.

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Sahm, David Karl. "The classical mechanics of mode-mode energy transfer in polyatomic molecules." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/29997.

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Agbo, Johnson K. "Kinetics of peptide isomerization and vibrational energy flow in biological molecules /." abstract and full text PDF (UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3280746.

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Thesis (Ph. D.)--University of Nevada, Reno, 2007.
"August 2007." Includes bibliographical references. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2008]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.

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Anderson, Tomas. "Scattering of thermal energy atoms and molecules from cold copper surfaces /." Göteborg : Göteborg university, 2001. http://catalogue.bnf.fr/ark:/12148/cb40192699j.

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Lühr, Armin. "Collisions of low-energy antiprotons and protons with atoms and molecules." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2010. http://dx.doi.org/10.18452/16084.

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In dieser Arbeit wird eine, zeitabhängige, nicht störungstheoretische numerische Methode entwickelt, welche Ionisation und Anregung von Atomen oder Molekülen in Stößen mit entweder PB oder P beschreibt und auf der impact-parameter Methode basiert. Es wird eine spektrale close-coupling Methode verwendet, um die zeitabhängige Schrödinger-Gleichung zu lösen, in welcher die Wellenfunktion in (effektive) Ein- oder Zwei-Elektronen-Eigenzustände des Targets entwickelt wird. Dies beinhaltet auch eine erstmalige volle Zwei-Elektronen-Beschreibung von H2 in PB-Stößen. Rechnungen werden für PB-Stöße mit H, H2+ und H2 sowie He und den Alkaliatomen Li, Na, K und Rb durchgeführt. Daten für P-Stöße werden für H2 und die Alkaliatomen Li, Na und K erzielt. Die Methode wird durch einen detaillierten Vergleich der erhaltenen Ergebnisse für P-Stöße und für PB + He mit Literaturdaten verifiziert. Andererseits ergänzen die totalen und differentiellen Wirkungsquerschnitte für Ionisation und Anregung der Targets in PB-Stößen die spärliche Literatur. Sowohl die Resultate für verschiedene Targets als auch für PB- und P-Stöße werden miteinander verglichen. Ein Schwerpunkt dieser Arbeit liegt auf der Untersuchung von PB + H2, welche die Abhängigkeit der Wirkungsquerschnitte vom Kernabstand und von der relativen Ausrichtung der molekularen Achse beinhaltet. Weiterhin werden Ergebnisse mit Ein-Elektronen-Modellpotentialen erzielt und mit der vollen Zwei-Elektronen-Beschreibung von H2 verglichen. Außerdem werden Energieverluste in PB-Stößen bestimmt.
In this work a nonperturbative, time-dependent numerical approach is developed which describes ionization and excitation of atoms or molecules by either PB or P impact based on the impact-parameter method. A spectral close-coupling method is employed for solving the time-dependent Schrödinger equation in which the scattering wave function is expanded in (effective) one- or two-electron eigenstates of the target. This includes for the first time a full two-electron, two-center description of the H2 molecule in PB collisions. The radial part of the one-electron eigenstates is expanded in B splines while the two-electron basis is obtained with a configuration-interaction approach. Calculations are performed for PB collisions with H, H2+, and H2 as well as with He and alkali-metal atoms Li, Na, K, and Rb. Additionally, data are obtained for P collisions with H2, Li, Na, and K. The developed method is tested and validated by detailed comparison of the present findings for P impacts and for PB + He collisions with literature data. On the other hand, total and differential cross sections for ionization and excitation of the targets by PB impact complement the sparse literature data of this kind. Results gained from different targets as well as from PB and P impact are compared with each other and assessed. Furthermore, results obtained with one-electron model potentials are compared to the full two-electron description of H2. Finally, stopping powers for PB impacts are determined.

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Bylin, Johan. "Analysis of a spin-particle tunnelling junction." Thesis, Uppsala universitet, Materialteori, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-254984.

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This project is to analyse the energy spectrum of a spin-molecular tunnelling junction which is composed of molecules confined between two conducting metallic leads. By letting a continuous stream of electrons flow across the junction the molecules can interact with each other with an indirect force called exchange interaction, and those exchange interactions which are of interest in this project are described by models called the Heisenberg, the Ising and the Dzyaloshinski-Moriya models. The molecules may also interact with themselves anisotropically and if there is an external magnetic field there will be yet another kind of interaction. The goal of this project is to see the contribution of all these spin interactions and how they affect the resulting energy spectrum under the variation of the junction's chemical potential and the voltage bias between the leads. This project is of a theoretical nature where the models are analytically adapted for a restricted scenario and is later on numerically calculated to be graphed and analysed. The models are restricted to only consider molecules of same spin and approximated to only consider interactions between closest neighbouring molecules. The results are composed of both analytically derived energy values and numerical computed values which show that there exists certain critical values of the variation parameters which naturally splits the ground state of the system and that the self-interaction may further split the degenerate ground state. A possible outcome of these result could be the possibility to control the magnetic order of the molecules to either be locked in an anti-ferromagnetic configuration or be easily mixed by manipulating the chemical potential or the voltage bias.
Detta projekt handlar om att analysera energispektrumet från en spinn-molekyl-tunnelkor-sning som består av molekyler instängda mellan två ledande metaller. När en kontinuerlig elektronström korsar tunnelkorsningen så kan molekylerna växelverka med varandra via en indirekt kraft kallad utbytesinteraktion, och de utbytesinteraktioner som är relevanta i denna uppställning beskrivs av de så kallade Heisenberg-, Ising- och Dzyaloshinski-Moriya-modellerna. Molekylerna kan också växelverka med sig själva anisotropt och om det finns ett externt magnetfält så tillkommer ytterligare en interaktionsterm. Målet för detta projekt är att se hur alla dessa spinnbidrag påverkar det slutliga energispektrumet under variation av korsningens kemiska potential och spänningen mellan metalledarna. Projektet är teoretiskt lagt på så sätt att modellerna är analytiskt anpassade för ett begränsat scenario samt att de är numeriskt beräknade så att energispektrumet kan plottas i grafer och analyseras. Modellerna är begränsade för molekyler av samma spinn och är approximerade så att endast närmsta-granne-interaktioner är beaktade. Resultaten är uppdelade i både analytiskt framtagna energivärden samt numeriskt beräknande energinivåer och båda visar att det finns kritiska värden på variationsparametrarna som automatiskt delar grundtillståndet för systemet samt att självinteraktionerna ytterligare kan dela det degenererade grundtillståndet. Ett möjligt utfall av dessa resultat är att de kan användas till att kontrollera systemets magnetiska ordning på så sätt att det antingen är låst i en antiferromagnetisk konfiguration eller med enkelhet kan mixas genom att ändra den kemiska potentialen eller spänningen mellan metalledarna.

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28

Williams, Robert Keith. "Molecular conformational studies of deoxyribonucleic acid by potential energy minimization with normal mode analysis." Thesis, Keele University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292541.

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29

Sjödin, Marica. "Resonant multi-photon ionisation studies of high-energy states in small molecules." Doctoral thesis, KTH, Physics, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-409.

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This thesis describes separate studies of high-energy Rydberg and ion-pair states in small molecules using resonant multi-photon ionisation spectroscopy.

* OODR/REMPI study of ungerade Rydberg states in O₂

The energy region between 75000 and 99900 cm^-1 of O₂ has been studied using optical-optical double resonance (OODR) with resonance enhanced multi-photon ionisation (REMPI). Three-photon excitation via single rotational levels of the b(¹Σ⁺_g ) valence state was used to study np (n=3–10) and nf (n=4–9) Rydberg states converging on O₂⁺X(²Π_1/2,g) and X(²Π_3/2,g). The excitation pathway picks out non-predissociated states that are singlet in the (Λ,S) coupling scheme – suitable for np states for n ≥8, or are linear combinations of equal weight of singlet and triplet-spin states in the (Ω,ω) coupling scheme which was found to be suitable for nf states for all values of n.

* OTR/RI study of Rydberg and ion-pair states in I₂

Optical triple resonance (OTR) together with resonance ionisation (RI) has been used to study the ungerade manifold of molecular iodine between 57000 and 73000 cm^-1 via the E 0_g⁺(³P₂) ion-pair state. Two 6s Rydberg states with 0 +u symmetry based on excited states of the ion core have been observed.

During this study we also observed electric-field-induced mixing of nearly isoenergetic rovibrational levels of the E0_gP⁺(³P₂) and D0u+(³P₂) ion-pair states. Detectable mixing with an applied field of 1kV/cm occurs over a range of energy level separations of ≤0.3 cm^-1.

* (2+1)and (3+1) REMPI study of pyrrole (C₄H₅N) The two- and three-photon REMPI spectra of Rydberg states of pyrrole (C₄H₅N) have been recorded using circularly and linearly polarised light. The spectra were compared to the single-photon absorption spectrum of pyrrole and a similar study of furan (C₄H₄O). Although the ionisation spectra of pyrrole were considerably weaker than corresponding furan spectra, a strong propensity for excitation of d series with two photons and p and f series with three photons was observed for both molecules. The totally symmetric nd-Rydberg series associated with the first ionisation energy, [A₂]nd;A₁, was identified from n=3 to n=15 and extrapolated to obtain IE1.

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30

Sjödin, Marica. "Resonant multi-photon ionisation studies of high-energy states in small molecules /." Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-409.

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31

Sjödin, Marica. "Resonant multi-photon ionisation studies of high-energy states in diatomic molecules /." Stockholm, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-356.

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32

Rice, J. E. "Analytic energy derivatives and their application to small and medium-sized molecules." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372299.

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33

Felker, Peter Mark Zewail Ahmed H. Zewail Ahmed H. "Picosecond dynamics of intramolecular vibrational-energy redistribution (IVR) in jet-cooled molecules /." Diss., Pasadena, Calif. : California Institute of Technology, 1985. http://resolver.caltech.edu/CaltechETD:etd-04072008-152253.

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34

Langer, Peter. "Jacobi-Davidson type methods for computing rovibronic energy levels of triatomic molecules." Berlin Logos-Verl, 2008. http://d-nb.info/995471347/04.

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35

Wang, Youqi Weinberg W. H. "Electron energy loss spectroscopic study of small molecules on transition metal surfaces /." Diss., Pasadena, Calif. : California Institute of Technology, 1995. http://resolver.caltech.edu/CaltechETD:etd-10122007-112248.

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36

Brown, Trevor C. "Studies in collisional energy transfer of highly rotationally and vibrationally excited molecules /." Title page, contents and abstract only, 1988. http://web4.library.adelaide.edu.au/theses/09PH/09phb881.pdf.

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Thesis (Ph. D.)--University of Adelaide, 1989.
Typescript (Processed). Errata slip inserted. Spine title: Studies in collisional energy transfer of highly excited molecules. Includes bibliographical references (leaves 143-167).

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37

Hu, He. "INFRARED STUDY OF CHARGE TRANSFER BETWEEN ORGANIC MOLECULES AND SEMICONDUCTORS." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1522444435463025.

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38

Li, Xiang. "Organic Molecules for Field Effect Transistors and Redox Flow Batteries." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1601396172154889.

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39

Lowis, D. R. "Application of theoretical methods to the study of small molecules in solution." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240696.

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40

Norlin, Nils. "Extended Förster Theory of Electronic Energy Transport within Pairs of Reorienting Chromophoric Molecules." Doctoral thesis, Umeå universitet, Kemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22471.

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An extended Förster theory (EFT), previously derived (L. B.-Å. Johansson et al. J. Chem. Phys., 1996,105) has theoretically been adapted and used in simulations of donor-acceptor energy transfer (DAET), which is a process often referred to as FRET. It was shown that the classical Förster theory is only valid in the initial part of the fluorescence decay. In this thesis an EFT is derived and outlined for electronic energy transport between two fluorescent molecules which are chemically identical, but photophysically non-identical. The energy migration within such asymmetric pairs is partially reversible and therefore referred to as partial donor-donor energy migration (PDDEM). The previously derived model of PDDEM (S. V. Kalinin et al. Spectrochim Acta Part A, 2002,58) is an approximation of the EFT. In particular, the EFT accounts for the time-dependent reorientations as well as the distance that influence the rate of electronic energy migration. The reorientation of the fluorophores transition dipole moments has been simulated using Brownian dynamics. As a result, the related “k2-problem” has been solved. The EFT of PDDEM has also been studied regarding the effect of PDDEM on experimental observables e.g. quantum yield of fluorescence and steady-state anisotropies

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41

Joo, Hyun. "Exploring potential energy sources and reaction mechanisms of inorganic molecules by computational methods." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Fall/Dissertation/JOO_HYUN_55.pdf.

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42

Davies, P. R. "Reactions of molecules at surfaces studied by photoelectron and electron energy loss spectroscopies." Thesis, Cardiff University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305213.

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43

Shirasaki, Yasuhiro. "Efficient Föster energy transfer : from phosphorescent organic molecules to J-aggregate thin film." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46500.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.
Includes bibliographical references (p. 53-54).
This thesis demonstrates the first ever use of Forster resonance energy transfer (FRET) to increase the quantum efficiency of a electrically pumped J-aggregate light emitting device (JLED). J-aggregate thin films are highly absorptive films that have potential applications in a new class of optoelectronic devices, known as polaritonic devices. These devices, which utilize strong coupling between light and matter, include room temperature low power optical switches and low threshold lasers. Recent work has shown that a J-aggregate strong-coupling device can be powered not just optically but also electrically. However, since J aggregates are engineered for their optical and not electrical properties, exciting them electrically is very inefficient. JLED efficiency can be improved by first exciting phosphors that readily form excitons and then employing FRET to excite the J aggregates. Attaining high efficiency can make electrical pumping a viable option to power polaritonic devices.
by Yasuhiro Shirasaki.
M.Eng.

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44

Barclay, V. J. (Victoria Jean) Carleton University Dissertation Chemistry. "Balanced basis sets in the calculation of potential energy curves for diatomic molecules." Ottawa, 1990.

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45

Norlin, Nils. "Extended Förster theory of electronic energy transport within pairs of reorienting chromophoric molecules /." Umeå : Department of Chemistry, Umeå University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-22471.

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46

Olaoye, Olufemi Opeyemi. "Density functional calculation of simple molecules." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20345.

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Thesis (MSc)--Stellenbosch University, 2012.
AFRIKAANSE OPSOMMING: Berekeninge met Density Functional Theory (DFT) is ’n nuttige tegniek om die dinamika van molekules op potensiële energievlakke te verstaan. Beginnende met ’n prototipe molekuul formaldimien, wat die kern vorm van die groter fotochromiese molekuul dithizonatophenyl kwik (DPM), word die modellering van die molekuul meer ingewikkeld tot laasgenoemde bestudeer kan word asook sy fotochromiese afgeleides wat vervanging van elektronryk en elektronarm radikale by orto, meta en para posisies van die phenyl ringe insluit. DFT berekeninge word met spektra van Absorpsiespektroskopie met UV en sigbare lig asook tyd opgeloste spektra, verkry dmv femtosekondespektroskopie, vergelyk. In pol^ere aprotiese, pol^ere protiese en nie-pol^ere oplosmiddels, isomeriseer die molekuul om die C=N dubbelbinding. Daar kan tussen die twee isomere onderskei word deur dat die een in oplossing in sy grondtoestand blou en die ander een oranje voorkom. Die isomerisering is’n fotogeinduseerde proses. Die optimering van die molekul^ere struktuur, absorpsiespektra, oplosmiddel-afhanklikheid, en potensiële energievlak metings van die molekuul word bestudeer. Die sterk/swak wisselwerking wat in pol^ere protiese/aprotiese oplosmiddels verskyn word geopenbaar deur die hoe/lae absorpsie van die sekond^ere bande van die molekules. Daar is gevind dat die absorpsiespektra van DPM bathochromies in oplosmiddels met hoë diëlektriese konstantes is. Vir die potensiële energievlak berekeninge van die grondtoestand word rigiede en ontspanne metodes gebruik waar laasgenoemde met gebroke simmetrie berekeninge verkry word. Van alle metodes wat vir berekeninge gebruik was, gee die B3LYP/CEP-31G metode die beste benadering aan eksperimentele data. Alle berekeninge word gedoen met twee bekende sagteware pakkette; Amsterdam Density Functional (ADF) en Gaussian, wat op twee verskillende DFT metodes gebaseer is.
ENGLISH ABSTRACT: Density functional theory is a useful computational tool in the understanding of molecular dynamics on potential energy surfaces. Starting with a prototype molecule formaldimine, the photochromic molecule dithizonatophenylmercury II (DPM) and a set of its photochromic derivatives, (involving substitutions of electron donating and electron withdrawing substituents at ortho, meta and para positions of the dithizonato phenyl rings), are studied through density functional calculation in comparison with steady state absorption spectra obtained from UV-Visible and femto second spectroscopy experiments. In polar aprotic, polar protic and non-polar solvents these molecules isomerise around C=N double bond chromophore, from orange electronic ground states to blue electronic ground states upon photo-excitation. We investigate the structural optimisations, the absorption spectra, the solvent dependence and the potential energy surface (PES) of these molecules. The strong (weak) interactions exhibited by the polar protic (aprotic) solvents used are revealed through high (low) absorbance in the secondary bands of these molecules. The absorption spectra of DPM are found to be bathochromic in solvents with high dielectric constants. For the ground state PES calculation we make use of rigid and relaxed methods, and the latter is obtained through broken symmetry calculation. Of all the methods used in calculation, B3LYP/CEP-31G method gives the best approximation to the experimental data. All calculations are done using the two renown software, Amsterdam Density Functional (ADF) and Gaussian, availing their different density functional methods.

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47

Thompson, Mark R. "The multielectron dissociative ionization of molecules probed by intense laser fields." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363715.

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48

Stansfield, R. A. "Computer simulations on the sputtering of solid surfaces by high energy ions and molecules." Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305657.

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49

Hunniford, C. A. "Ionization and fragmentation of biologically relevant molecules by low energy ions and UV photons." Thesis, Queen's University Belfast, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437413.

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50

Shibano, Yuki. "Energy and Electron Transfer in Novel Conjugated Molecules and Their Application to Photoelectrochemical Devices." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/49146.

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学位授与大学：京都大学 ; 取得学位: 博士(工学) ; 学位授与年月日: 2007-09-25 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2867号 ; 請求記号: 新制/工/1421 ; 整理番号: 25552
Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第13396号
工博第2867号
新制||工||1421(附属図書館)
25552
UT51-2007-Q797
京都大学大学院工学研究科分子工学専攻
(主査)教授今堀博, 教授川﨑昌博, 教授榊茂好
学位規則第4条第1項該当

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Dissertations / Theses on the topic 'ENERGY MOLECULES'

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