Dissertations / Theses: 'Raman resonance'

1

Liu, Xiaohua. "Resonance raman studies of hemoproteins." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/27170.

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Weigel, Alexander. "Femtosecond stimulated resonance Raman spectroscopy." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2011. http://dx.doi.org/10.18452/16302.

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Femtosekundenaufgelöste Ramanspektroskopie ist ein leistungsfähiges Werkzeug, um die Schwingungsentwicklung eines angeregten Chromophors in Echtzeit zu studieren. In dieser Arbeit wurde ein durchstimmbares Ramanspektrometer mit 10 cm-1 spektraler und 50--100 fs zeitlicher Auflösung entwickelt und für eine Anwendung auf flavinbasierte Photorezeptoren optimiert. Es wird der Einfluß der Resonanzbedingungen auf das transientes Ramanspektrum charakterisiert. Die Dynamik des angeregten Zustandes wird zuerst für den Modellphotoschalter Stilben untersucht, ausgehend sowohl vom cis-, als auch vom trans-Isomer. Intensitätsabnahme, spektrale Verschiebung und Bandenverschmälerung liefern Einblicke in die Schwingungsrelaxation des angeregten Chromophors. Wellenpaketbewegung und anharmonische Kopplung werden als Oszillationen beobachtet. Für das "Mutter"-Cyanin 1,1''-Diethyl-2,2''-pyridocyaniniodid wird die Isomerisierung bis in den Grundzustand verfolgt. Ramanspektren des Franck-Condon-Zustandes, des intermediär gebildeten heissen Grundzustandes und der Isomerisierungsprodukte werden erhalten. Als Grundlage für Experimente an Flavoproteinen werden die Eigenschaften des angeregten Flavinchromophors in Lösung untersucht. Transiente Absorptions- und Fluoreszenzexperimente weisen auf den Einfluss dynamischer polarer Solvatation hin. Es werden Ramanspektren des angeregten Zustandes von Flavin aufgenommen und die Schwingungsbanden zugeordnet. Populationsverminderung durch den Ramanimpuls wird als potentielles Artefakt in zeitaufgelösten Messungen identifiziert; der Effekt wird aber auch genutzt, um Wellenpaketbewegung im angeregten Zustand zu markieren. Die Photorezeptormutanten BlrB-L66F und Slr1694-Y8F werden mit transienter Absorption studiert. Dabei wird die Bildung des Signalzustandes und Flavinreduktion durch ein Tryptophan beobachtet. Die Anwendung des entwickelten Ramanspektrometers auf biologische Proben wird in einem ersten Experiment an Glucose Oxidase demonstriert.
Femtosecond stimulated Raman spectroscopy is a powerful tool that allows to study the structural relaxation of an excited chromophore directly in time. In this work a tunable Raman spectrometer with 10 cm-1 spectral and 50-100 fs temporal resolution was developed, and the technique was advanced towards applications to flavin-based proteins. With this device the influence of resonance conditions on the transient Raman spectrum is characterized. Excited-state dynamics is first investigated for the model photoswitch stilbene, starting from both the cis and the trans isomers. Decay, spectral shift, and narrowing of individual bands provide insight into the vibrational relaxation of the excited chromophore. Wavepacket motion and anharmonic coupling is seen as oscillations. Isomerization is followed to the ground state for the "parent" cyanine 1,1''-diethyl-2,2''-pyrido cyanine iodide. From a global analysis, Raman spectra for the Franck-Condon region, the intermediately populated hot ground state, and the isomerization products are obtained. As a basis for experiments on flavoproteins, the excited-state properties of the pure flavin chromophore are studied in solution. Transient absorption and fluorescence experiments suggest an influence of dynamic polar solvation on the electronic properties of the excited state. Raman spectra from the flavin excited state are recorded and the vibrational bands assigned. Population depletion by the Raman pulse is identified as a potential artefact, but the effect is also used to mark wavepacket motion in the excited state. The photoreceptor mutants BlrB-L66F and Slr1694-Y8F are studied by transient absorption; signaling state formation and flavin reduction by a semiconserved tryptophan are seen, respectively. The application of femtosecond Raman spectroscopy to biological samples is demonstrated in a first experiment on glucose oxidase.

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Hernandez-Santana, Aaron. "Surface-enhanced resonance Raman coded beads." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443118.

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4

Smith, Susan James. "A resonance Raman and surface enhanced resonance Raman study of cytochrome P450s and their substrate/inhibitor interactions." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288604.

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5

Feng, Sibo. "Resonance raman studies of some dye molecules." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/27432.

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6

Behnke, Shelby Lee. "Resonance Raman Investigations of [NiFe] Hydrogenase Models." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1479728987893667.

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7

Sullivan, Ann Marie G. "Resonance Raman spectra of chloroperoxidase reaction intermediates." VCU Scholars Compass, 1992. https://scholarscompass.vcu.edu/etd/5610.

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Chloroperoxidase is an enzyme that exhibits spectroscopic and structural properties similar to cytochrome P-450. Chloroperoxidase is studied using resonance Raman spectroscopy to characterize the reaction intermediates of the physiological mechanism, known as compounds I and II. Compound I is formed by a two electron oxidation of the resting enzyme and contains an Fe(IV) porphyrin ℼ cation radical. A one electron reduction of compound I produces the compound II intermediate which contains an oxy-ferryl [Fe(IV)=O] iron heme. Chloroperoxidase is a heme enzyme of substantial interest because of its structural similarity to cytochrome P-450 and because of its diverse reactivity. Chloroperoxidase can function as a peroxidase, catalase, haloperoxidase and to some extent as a monooxygenase. Chloroperoxidase is excreted by the mold, Caldariomyces fumago and contains the iron protoporphyrin IX prosthetic group. From previous spectroscopic data, it has been determined that native chloroperoxidase is a penta-coordinate heme with a cysteine thiolate axial ligand. The reaction intermediates of chloroperoxidase, compounds I and II, are among the least stable of the known peroxidase intermediates. However, they can be stabilized somewhat by avoiding the use of hydrogen peroxide as the oxidant. Because of catalase activity of this enzyme, hydrogen peroxide can act as both oxidant and substrate causing the rapid turnover of the enzyme. For the generation of the chloroperoxidase intermediates, the enzyme is mixed with an equal volume of oxidant in a Ballou four jet mixer fed by two 100 ml syringes which produces a continuous jet of newly formed intermediate. Compound I was formed by mixing the enzyme with a 15 fold excess of peracetic acid and compound II was formed by premixing the enzyme with a 100 fold excess of a substrate, ascorbic acid, then mixing with a 30 fold excess of peracetic acid. The observed resonance Raman frequencies of the chloroperoxidase intermediates are similar to those observed for horseradish peroxidase, however there are a number of reproducible differences in frequencies due to differences in ground state symmetry or axial ligation. The in-plane skeletal modes in the resonance Raman spectrum of compound II can be assigned as follows: v10 at 1645 cm^-¹, v₃₇ at 1606 cm^-¹, v₂ at 1582 cm^-¹, v₃₈ or v¹₁₁ at 1554 cm^-¹, v₃ at 1511 cm^-¹, v₂₈ at 1476 cm^-¹, vinyl =CH₂ wags at 1345 and 1434 cm^-¹, v₂₀ or v₂₉ at 1396 cm^-¹, and v₄ at 1374 cm^-¹. These assignments are close to those previously reported for horseradish peroxidase compound II. Band assignments for compound I are v₁₀ at 1647 cm^-¹, v37 at 1619 cm^-¹, v₂ at 1589 cm^-¹ and v₄ at 1358 cm^-¹. The band at 1647 cm^-¹ is depolarized, whereas, the bands at 1619 and 1589 cm^-¹ are polarized. The oxy ferryl [Fe(IV)=O] frequency has been observed at approximately 790 cm-¹ in horseradish peroxidase. In chloroperoxidase, two bands at 790 and 753 cm^-¹ are present in both compounds I and II resonance Raman spectra. Upon ¹⁸O-substitution these bands shift approximately 30 cm^-¹ as predicted by simple force constant calculations.

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Tanaka, Tomoyoshi. "Resonance raman and surface enhanced raman studies of hemeproteins and model compounds." Diss., Georgia Institute of Technology, 1986. http://hdl.handle.net/1853/27678.

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9

Short, Billy Joe. "Ultraviolet resonance Raman enhancements in the detection of explosives." Thesis, Monterey, Calif. : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Jun/09Jun%5FShort.pdf.

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Thesis (M.S. in Applied Physics)--Naval Postgraduate School, June 2009.
Thesis Advisor(s): Smith, Craig F. "June 2009." Description based on title screen as viewed on 14 July 2009. Author(s) subject terms: Raman spectroscopy, standoff detection, high explosives, explosive detection, inelastic scattering, resonance Raman. Includes bibliographical references (p. 77-80). Also available in print.

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Rwere, Freeborn. "Resonance Raman studies of isotopically labeled heme proteins." [Milwaukee, Wis.] : e-Publications@Marquette, 2009. http://epublications.marquette.edu/dissertations_mu/22.

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Oprescu, Dan. "The theory and practice of resonance Raman spectroscopy." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242967.

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McCabe, Ailie Fiona. "Remote detection using surface enhanced resonance Raman scattering." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401340.

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Cunningham, Dale. "Fundamental studies of surface enhanced resonance Raman spectroscopy." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438120.

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Russell, Malcolm Peter. "Resonance raman spectroscopic studies of bilirubin and biliverdin." Thesis, University of York, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358273.

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Brown, Sandra Dawn Marie 1968. "Resonance Raman spectroscopy of single-walled carbon nanotubes." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/36101.

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Physics, 2000.
Includes bibliographical references (leaves 169-180).
The unusual one-dimensional properties of phonons in crystalline arrays of carbon nanotubes is presented. The main technique for probing the phonon spectra is Raman spectroscopy and the many unique and unusual features of the Raman spectra of carbon nanotubes are highlighted. Various features of the first-order Raman spectra are emphasized, with regard to their 1D behavior and special characteristics, such as the radial breathing mode, and the tangential G-band (1600cm-') associated with carbon atom displacements on the cylindrical shell of the nanotube (C-C stretching motion of the atoms). The strong coupling between electrons and phonons in this one-dimensional system furthermore gives rise to highly unusual resonance Raman spectra, and unique features in the Stokes and anti-Stokes Raman spectra. The Raman tangential G-band feature associated with semiconducting nanotubes have a different characteristic lineshape than those associated with metallic carbon nanotubes. The differences in the electronic density of states of metallic nanotubes relative to semiconducting nanotubes leads to differing resonance behaviors, thus resulting in differing lineshapes in the tangential G-band region of the Raman spectrum. A diameter selective resonance process allows resonant enhancement of the Raman tangential G-band for the metallic nanotubes in a narrow range of laser excitation energies for a sample of nanotubes with a narrow distribution of diameters. The anti-Stokes Raman spectra of single-wall carbon nanotubes (SWNTs) are unique relative to other crystalline systems, especially in exhibiting large asymmetries with regard to their corresponding Stokes spectra. This asymmetry is due to the unique resonant enhancement phenomena arising from their one-dimensional electronic (1D) density of states. The anti-Stokes spectra are therefore selective of specific carbon nanotubes, as previously reported for the Stokes spectra, but the anti-Stokes spectra are selective of different single wall nanotubes than for the corresponding Stokes spectra at a given laser excitation energy Elaser. The unique behavior of the anti-Stokes spectra for the first-order tangential modes, which allow accurate identification of the range of Easer where metallic nanotubes contribute to the resonant Raman spectra, is discussed. A detailed Breit-Wigner-Fano lineshape analysis of the tangential G-band features attributable to metallic carbon nanotubes is presented. Only two components are needed to account for the entire G-band, both with predominantly A (Alg) symmetry, and the nanotube curvature callses the differences in their frequencies and gives rise to the Breit-Wigner-Fano coupling. Analysis of the second-order resonant Raman spectra of single-walled carbon nanotubes using different laser energies ill the range 1.58-2.71 eV is presented. Major emphasis is given to the overtones and combination modes associated with the two dominant features of the first-order spectra, the radial breathing mode and the tangential mode. Both of these modes, as well as their second-order counterparts, are associated with resonant enhancement phenomena arising from electron-phonon coupling to the unique one-dimensional density of electronic states for the single-wall carbon nanotubes. Overtones, combination modes, and the behavior of the D band and G' band in the Stokes and anti-Stokes spectra are also discussed briefly. Comparison between the Stokes and anti-Stokes spectra show that the resonance Raman process is stronger for metallic than for semiconducting nanotubes. The surface-enhanced resonant Raman scattering (SERRS) spectra of single-walled carbon nanotubes (SNWNTs) adsorbed on silver and gold metal island films and on colloidal silver cluster substrates were investigated using different laser excitation wavelengths. The observed enhancement in the SERRS signal of the SWNTs results from: (1) an "electromagnetic" SERS enhancement due to resonances between optical fields and the electronic excitations in the metallic nanostructures, (2) a "'chemical" SERS enhancement due to the interaction between the SNTs an(l the metal surfaces, and (3) a selective resonance Ramrran effect between the incidellt and scattered photons and electronic transitions between the D van Hove singularities in the electronic density of states of metallic and semiconducting nanotubes. We have observed changes in the relative intensities and shifts in the peak freqllencies of several vibrational modes of the SWNTs upon adsorption on a metal sulrface. which indicate a specific interaction of the nanotubes with the mnetals urf:ace. Chllangesi n the resonant Raman spectra due to interaction with the silver or gold surfaces are al)parent in the second-order Raman bands, especially in the (iislpersive features. such as the secondor( lder Raman G' band, which ulpshifts in the SERRS spectra relative to the resonant Raman scattering (RRS) spectra, providing evidence of a, significant perturbation of the elec(tronic levels for the adsorbed( nanotlbes. In addition, tlhe SER spectra show an additional enhancement of the Ramlan signal for slpecific featulres in the vibrational spectra of the metallic( nanotlbes, in contrast to the case for the sermlicon(lIictinInga notllbes for which the normal RRS an(l SERRS spectral profiles are very similar. These results can be rationalized in terms of a specific charge--transfer enhanc(ement effect for the metallic nanotllbes. The srface-enhanced Raman spectroscopy stlludies show that the coupling, which results in the Breit---Wigner- Fano lineslhape of soni of the R.anlma features associated with metallic nanotubes, is to a surface plasmon based electronic continuum.
by Sandra Dawn Marie Brown.
Ph.D.

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Mattioli, Tony A. (Tony Andrea) Carleton University Dissertation Chemistry. "Resonance raman study of nickel (II) pheophytin a." Ottawa, 1988.

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Lin, Shun-hua. "Resonance raman studies of hemoproteins and model heme complexes." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/30311.

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Boustany, Nada. "Characterization of mucosal dysplasia with ultraviolet resonance Raman spectroscopy." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/9809.

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Thesis (Ph. D.)--Harvard--Massachusetts Institute of Technology Division of Health Sciences and Technology, 1997.
"August, 1997."
Includes bibliographical references.
by Nada Boustany.
Ph.D.

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Foster, Catherine. "Resonance raman intensity analysis of chlorine dioxide in solution /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/11595.

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PICCO, ANDREA. "Resonance effects in the Raman analysis of sige nanostructures." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/28617.

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In the last two decades, attention has raised towards SiGe nanostructures for applications in microelectronics and optoelectronics. Many efforts have been payed in order to control the growth of the nanostructures and characterize their structural properties: for this purpose, a wide series of different experimental techniques have been developed. Raman spectroscopy of SiGe is commonly used to obtain information about the average values of composition and strain inside the nanostructures. Actually, due to the lack of data about the Raman efficiency of SiGe as a function of the alloy composition and the excitation light frequency, it is not possible to extract information about the composition profiles which are known to be present inside the structures and deeply affect their optoelectronic properties. In this work, the Raman efficiency of SiGe is measured across the whole compositional range for six different excitation light energies in the UV and VIS range. Strong resonances in the Raman efficiency of SiGe are observed, related to the direct electronic transitions in the material: their origin is explained by means of the theory and confirmed by semiempirical calculations. Then, a numerical tool is presented, which is able to analyze the Raman spectrum of an inhomogeneous SiGe structure and extract information about its internal composition profile by taking into account the effects of the resonance on the SiGe Raman efficiency. The methodology is validated by means of a calibrated SiGe sample, and applied to the study of SiGe islands. The internal composition profile of the islands obtained with this methodology is in good agreement with the results of independent techniques. Finally, the powers and limitations of the methodology are investigated.

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Leonard, James Delmas. "Ultraviolet resonance Raman and picosecond transient Raman studies of trans-4,4'-diphenylstilbene and related compounds /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487868114111719.

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Rodriguez, Arturo A. (Arturo Angel). "Raman and NMR Relaxation Studies of Molecular Dynamics in Liquids." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc330818/.

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Raman vibrational bands are sensitive to fluctuations in the molecular environment. Variations in the bandwidth and peak position can then be utilized to monitor molecular forces and interactions present in condense phases. Nuclear Magnetic Resonance (NMR) provides a convenient probe for the study of molecular reorientation in liquids since nuclear spin relaxation times are dependent on the details of molecular motion. Presented here is the solvent study of the Raman bandwidths and frequency displacements of the mode of the compounds CH3MCI3 (M = C, Si, Ge, Sn) in a number of solvents of widely varying molecular structure. Also, a detailed isotope dilution study of the modes in CH2CI2/CD2CI2 mixtures is presented. In this set of experiments, I observed broadening of the v1 mode of CH2C12 upon dilution,which is the first experimental observation of such behavior. The temperature-dependent carbon-13 relaxation times and nuclear Overhauser enhancements in neat dichloromethane were measured. In this study we found that the molecular reorientation of this molecule was highly anisotropic, but could be well characterized assuming quasi-symmetric top behavior. In addition, in order to gain a more complete understanding of the reorientational dynamics in dichloromethane, we analyzed the 13-C NMR relaxation of CH2CI2 both in "inert" solvents of differing viscosities and in interactive solvents of varying Lewis basicities. Various theoretical models were also applied in order to characterize dichloromethane1s reorientational dynamics.

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Kabagambe, Benjamin. "Spectroscopic investigation of proteins : UV resonance Raman studies of apomyoglobin /." Saarbrücken, Germany : VDM Verlag Dr. Müller, 2008. http://etd.library.pitt.edu/ETD/available/etd-10232007-094038.

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Thesis (M.S.)--University of Pittsburgh, Department of Chemistry, 2007.
Thesis advisor: Sanford A. Asher. Also available as an electronic book in PDF on the University of Pittsburgh Library Web site. Bibliography: p. 37-41.

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Addison, Christopher James. "Investigating biomolecular structure using fiber-optic UV resonance Raman spectroscopy." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37016.

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The observation of biomolecular structure is critical for the fundamental understanding of biological function. In this work, Fiber-optic UV Resonance Raman Spectroscopy (FO-UVRRS) was employed to study a number of structure-function relationships. A suite of metal-containing dioxygenase enzymes were studied in order to determine the substrate protonation state in the enzyme-substrate complex. Two enzymes with a high degree of sequence identity were studied, where one naturally incorporates a Fe²⁺ metal and the other uses Mn²⁺. Both enzymes react with the same substrate to form an equivalent muconic semialdehyde product. The enzymes are capable of incorporating the non-native metal into the enzymes with no effect on the kinetic properties. The Raman results show that the nature of the metal has no effect on the substrate protonation state. The degradation of 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) by BphD in the biphenyl catabolic pathway was studied using FO-UVRRS. Previous reports suggest that enol-keto tautomerization was a critical step in the mechanism of the carbon-carbon bond hydrolase. Hydrolytically impaired variants of BphD were used to study the binding mode of HOPDA. The results show that HOPDA binds to these variants in a strained-enolate geometry and does not undergo an enol-keto tautomerization upon enzyme binding. A fundamental FO-UVRRS study of locked nucleic acid (LNA) olgiomers was performed. LNA bases contain a C4’ to O2’ methylene bridge within the furanose ring of the nucleotide. The research results show that incorporation of a LNA induces a conformational change in the glycosyl bond between the backbone and the base. The results also show that incorporation of an LNA base induces changes in the secondary structure of the nucleic acid. In another study, chemical contamination of synthetic DNA oligomers was observed using FO-UVRRS. The data showed that commercially-available oligomers purified using standard desalting conditions are contaminated with residual benzamide. The results show that a previously assigned –NH₂ scissors vibration in the Raman study of oligomers overlaps with a prominent benzamide vibrational band, calling into question these previous assignments. The results also demonstrate that the extent of benzamide contamination varies from sample-to-sample and between different commercial sources.

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Gutschank, Jörg [Verfasser]. "Implementation of coherent Raman detected electron paramagnetic resonance / Jörg Gutschank." Dortmund : Universitätsbibliothek Technische Universität Dortmund, 2005. http://d-nb.info/1011533111/34.

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Kier, Ruth. "Flow systems for use in surface enhanced resonance raman spectroscopy." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249054.

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Hughes, Mhairi Patricia Hughes. "Surface enhanced resonance Raman scattering as an in situ probe." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248287.

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Narula, Rohit. "Double resonance Raman spectra of graphene : a full 2D calculation." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/42161.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2007.
Includes bibliographical references (leaves 85-87).
Visible range Raman spectra of graphene are generated based on the double resonant process employing a full two-dimensional numerical calculation applying second-order perturbation theory. Tight binding expressions for both the TO phonon dispersion and the [pi] - [pi]* electronic bands are used, which are then fit to experimental or ab-initio results. We are able to reproduce the single-peak D mode of graphene at ~ 1380 cm-1 that is identical to experiment. A near linear shift in the D mode peak with changing incoming laser energy of 33 cm-1/eV is calculated. Our shift marginally underestimates the experimental shifts as most of the literature features specimens that contain a few or more layers of graphene through to graphite that ought to subtly alter their electronic and phonon dispersions. However, our approach is readily applicable to such homologous forms of graphene once we have available their electronic band structure and phonon dispersions.
by Rohit Narula.
S.M.

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Brar, Victor W. (Victor Watson) 1981. "Evaluations of single walled carbon nanotubes using resonance Raman spectroscopy." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32759.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2004.
Includes bibliographical references (p. 77-81).
This work reports the results of two studies which use resonance Raman scattering to evaluate the vibrational properties of single walled carbon nanotubes (SWNTs). In the first study, we report an evaluation of second-order combination and over-tone modes in highly ordered pyrolytic graphite (HOPG), in SWNT bundles, and in isolated SWNTs. We found both dispersive and non-dispersive Raman bands in the range 1650-2100 cm⁻¹, and we show that the appearance and frequency vs. laser energy E[laser] behavior of these features are in agreement with predictions from double resonance Raman theory. In the case of SWNTs, these second-order bands depend on the one-dimensional structure of SWNTs, and, at the single nanotube level, the spectra vary from tube to tube, depending on tube diameter and chirality, and on the energy of the van Hove singularity relative to E[laser]. In the second study, we present a theoretical method of predicting, to within a linear constant [beta], the frequency shift in the Raman features of a SWNT material as the Fermi level is changed by depletion or addition of electrons. This constant is then evaluated for different Raman modes in SWNTs by comparing theoretical predictions to experimental observations by Corio et al. , where the Fermi level of SWNT bundles is raised by electrochemical doping and Raman spectra are collected in situ. It is determined that for the G-band of SWNTs, the dependence of frequency on Fermi energy is /[beta][sub]G = 271cm⁻¹ per hole per C-atom for metallic SWNTs with d[sub]f [approximately]= 1.25 ± 0.20nm.
by Victor W. Brar.
S.B.

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Chinn, Sarah Cureton. "Raman and magnetic resonance investigations of vibrationally excited diatomic molecules /." Connect to Digital dissertations. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.

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Ribeiro, Mauro Carlos Costa. "Cálculo de perfis de excitação raman pelo método de transformada." Universidade de São Paulo, 1992. http://www.teses.usp.br/teses/disponiveis/46/46132/tde-03092010-161222/.

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O presente trabalho é um estudo detalhado do cálculo de perfis de excitação Raman pelo método de transformada. A principal característica do método é o emprego do espectro de absorção para gerar diretamente os perfis Raman. Os programas aqui desenvolvidos para microcomputador foram testados pela comparação com perfis conhecidos da literatura, e usados para o estudo teórico de novas possibilidades de modelagem em sistemas conhecidos e também aplicados para novas espécies. Investigamos, a nível teórico , o uso do método de transformada em casos onde ocorre interferência eletrônica, e em perfis de modos não-totalmente simétricos . As novas espécies estudadas pelo método de transformada foram os íons complexos [Zn(dmit)2 ]2- and [Ni(dmit)2]2- , além da espécie TiI4, onde calculamos simultaneamente o perfil da fundamental e de harmônicas, tanto Stokes como anti-Stokes, do modo totalmente simétrico de estiramento Ti - I. Através do ajuste das intensidades relativas dos vários perfis, foi possível obter a variação da distância de equilíbrio Ti - l no estado eletrônico excitado em relação ao fundamental
The present work is a detailed study on the calculation of Raman excitation profiles by the transform method . The main feature of the transform method is to use the absorption spectra to generate the Raman excitation profiles. The computer programs here developed were tested by comparison with known profiles from the literature, and used to explore new possibilities in modelling the Raman profiles of new chemical species, as well as to improve already investigated profiles . We investigated , by use of the transform method, cases where electronic interference must be taken into account, and Raman excitation profiles of non-totally simetric modes [Zn(dmit)2 ]2- and [Ni(dmit)2]2- were now studied for the first time by the transform method. For TiI4 of the resonance profiles for the v1 fundamental and overtones, both Stokes and anti-Stokes, were calculated with a single set of parameters being possible to evaluate the displacement of the Ti - I equilibrium distance in the resonance electronic state relative to the ground state

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Chan, Wing-sum. "Resonance Raman, time-resolved resonance Raman and density functional theory study of Benzoin diethyl phosphate, selected P-Hydroxy and P-methoxy substituted phenacyl ester phototrigger and model compounds." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36198821.

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33

Ong, Shing-yau, and 王承祐. "Time-resolved resonance raman investigation of selected arylnitrenes and their reactions." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31227740.

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34

Chan, Wing-sum, and 陳穎心. "Resonance Raman, time-resolved resonance Raman and density functional theory study of Benzoin diethyl phosphate, selected P-Hydroxy and P-methoxy substituted phenacyl ester phototrigger and model compounds." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36198821.

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35

Malard, L. M., D. Nishide, L. G. Dias, Rodrigo B. Capaz, A. P. Gomes, A. Jorio, C. A. Achete, et al. "Resonance Raman study of polyynes encapsulated in single-wall carbon nanotubes." American Physical Society, 2007. http://hdl.handle.net/2237/11303.

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36

Webb, Mark Adam. "Excited-state charge-transfer dynamics of azurin from resonance Raman spectroscopy." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0012/NQ59696.pdf.

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37

Mackin, Helen Catherine. "Resonance Raman studies of ligand binging in cobalt and iron hemoproteins." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/27163.

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38

Bruun, Sara [Verfasser], and Peter [Akademischer Betreuer] Hildebrandt. "Resonance Raman spectroscopy on microbial rhodopsins / Sara Bruun. Betreuer: Peter Hildebrandt." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1035505649/34.

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39

McNay, Graeme. "Advancing surface enhanced resonance Raman scattering (SERRS) techniques for biological detection." Thesis, University of Strathclyde, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438129.

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40

McCarney, Karen Michelle. "A flow cell surface enhanced resonance Raman scattering (SERRS) detection system." Thesis, University of Strathclyde, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426325.

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41

Molina-Contreras, J. R., C. Frausto-Reyes, C. I. Medel-Ruíz, and Ladrón de Guevara H. Pérez. "CdTe Raman Line Shape in Resonance: a Space Correlation Zone Study." Thesis, Sumy State University, 2015. http://essuir.sumdu.edu.ua/handle/123456789/42800.

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We show that the line shape of resonant Raman spectra of CdTe can be reproduced using the spatial correlation model (SCM). Our results show that the resonant Raman spectrum for a surface with a RMS of 430 nm is characterized by the presence of two intense sharp peaks located at frequencies corresponding to LO and 2LOmodes. The resonant Raman spectrum for a surface with a RMS of 6 nm on the other hand, can be reproduced using the contribution of high frequency phonons related with the acoustic transverse harmonics. These results suggest that under resonance conditions, such acoustic transverse modes define the line shape for a small size correlation region diameter. This study provides a new application of SCM to estimate the size grain of a surface where this information is not available.

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42

Maugeri, Pearson Thomas Maugeri. "Applications of resonance Raman spectroscopy to the study of bioinorganic macromolecules." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1512093478871388.

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43

Shadi, Iqbal Tahear. "Surface enhanced resonance Raman spectroscopy of dyes : semi-quantitative trace analysis." Thesis, University of Greenwich, 2005. http://gala.gre.ac.uk/6296/.

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Herein analysis of dye molecules has been carried out by means of surface enhanced Raman spectroscopy (SERS) and/or surface enhanced resonance Raman spectroscopy (SERRS) using citrate- and/or borohydride-reduced silver colloids employing laser exciting wavelengths equal to 514.5 and/or 632.8 nm. SERS and/or SERRS spectra are reported using, as model system probes, eight dye molecules which belong to several distinct chemical structural classes. Experimental protocols were developed and subsequently modified, as required, for each dye molecule examined. Vibrational spectroscopic profiles were obtained, where possible, with respect to concentration and pH dependence. SERS and/or SERRS vibrational bands provided unique fingerprint spectra for each dye molecule. In an attempt to develop novel applications of SERRS the technique has been used, in a kinetic investigation, to monitor and analyse the synthesis of the dye indigo carmine from indigo using a silver sol as the SERRS substrate/medium. In another study it was possible to differentiate between two structurally similar anthraquinones, alizarin and purpurin, using SERRS. It was also possible to demonstrate the existence of multiple molecular species of certain dye molecules, as a function of pH e.g. nuclear fast red, metanil yellow, purpurin and alizarin. For some dye molecules e.g. alcian blue it was possible to combine the linear regions of normal (non-resonance/non-enhanced) Raman and SERS/SERRS plots, thereby extending the dynamic range available for semi-quantitative analysis. The sensitivity of the SERS/SERRS technique for semi-quantitative trace analysis of eight dye molecules has been successfully demonstrated.

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44

Andrade, Gustavo Fernandes Souza. "Caracterização espectroscópica da tiossemicarbazona do formilferroceno (TFF) através das técnicas SERS (Surface-Enhanced Raman Scattering) e Raman ressonante." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/46/46132/tde-13092006-164920/.

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Nesta dissertação o processo de adsorção da tiossemicarbazona do formilferroceno (TFF) em eletrodos de prata e ouro, em soluções aquosas 0,1 mol.L-1 de KCl e de acetonitrila. 0,1 mol.L-1 de NaClO4, foi caracterizado através da técnica espectroscópica SERS. Verificou-se através das variações espectrais que a adsorção da TFF ocorre através dos átomos N1 do grupo imínico e do S do grupo tiocarbonílico. Os processos faradáicos do TFF foram monitorados pela técnica SERS e de absorção no UV-visível. Os espectros SERS para potencial de -1,4 V (Ag/AgCl) sugerem a formação de um novo composto, produto de redução da TFF, o aminometilferroceno. Através da técnica de absorção no UV-visível verificou-se, neste potencial, o aparecimento no espectro de absorção de uma nova banda em 240 nm, atribuída à formação de tiouréia. A identificação deste dois produtos de redução indica que, para o composto TFF, o mecanismo geral de redução dos derivados de tiossemicarbazonas é obedecido. Nenhuma variação espectral, tanto utilizando a técnica SERS como a absorção no UV-visível, foi detectada durante o processo redox FeII/FeIII (E1/2=0,55 V). Os comportamentos de adsorção e faradáico da tiossemicarbazida (TSC), em eletrodo de prata em soluções aquosas neutra e ácida, foram estudados através da técnica SERS. Verificou-se que em meios neutro e ácido, a TSC está adsorvida na configuração cis para potenciais próximos de 0,0 V, interagindo com a superfície através do átomo de S do grupo tiocarbonílico e dos átomos de H ligados ao N1 hidrazínico, através da formação de pares iônicos com os ânions Cl- adsorvidos. Para potenciais mais negativos, os íons cloreto deixam a superfície e a TSC sofre reorientação, assumindo a conformação trans. Não foi observado através da técnica SERS nenhum processo faradáico em solução ácida para potenciais negativos, como havia sido proposto na literatura. A não redução do composto foi confirmada através da técnica de eletroforese capilar. Foi estudado o comportamento Raman ressonante da TFF, verificando-se a ocorrência de um mínimo no perfil de excitação experimental devido à interferência destrutiva das transições dos grupos tiossemicarbazona e ferrocenil. Os perfis de excitação teóricos foram calculados utilizando o método da transformada e os resultados dos ajustes obtidos indicam que existe considerável distorção dos modos do grupo ferrocenil na transição eletrônica em 312 nm, atribuída a n-p* do grupo tiossemicarbazona, caracterizando uma grande interação eletrônica entre os cromóforos da TFF. Para comparar o comportamento Raman ressonante do TFF com o do ferroceno, os espectros Raman ressonante deste composto foram obtidos. Verificou-se que o ferroceno apresenta, também, o efeito Raman anti-ressonante, mas as bandas vibracionais do ferroceno apresentam perfis distintos dos apresentados no composto TFF, indicando que a incorporação do grupo tiossemicarbazona no anel ciclopentadienil modifica a estrutura eletrônica do grupo ferrocenil.
In this dissertation, the adsorption process of the formylpyridine thiosemicarbazone (TFF) at silver and gold surfaces in aqueous and in acetonitrile solutions has been characterized by using the SERS (Surface-enhanced Raman Scattering) technique. It has been verified that TFF adsorbs through N1 and S atoms on the metallic surfaces. The faradaic processes of TFF have been monitored through the SERS and UV-visible absorption spectroscopies. The SERS spectra at -1,4 V (Ag/AgCl) suggest aminomethylferrocene as one of the reduction products of TFF. By using the UV-visible absorption technique, it has been verified, at this potential, a new band at 240 nm in the spectrum, which indicates the presence of thiourea. The observation of these two reduction products has confirmed that the general reduction mechanism for thiosemicarbazonas works for TFF. Neither SERS nor UV-vis spectral changes have been observed during the redox process of FeII/FeIII (E1/2= 0,55 V). The adsorption and faradaic processes of thisemicarbazide (TSC) at silver electrode have also been studied by SERS technique. It has been verified that, in acidic and neutral media, the TSC is adsorbed through a cis-configuration at a potential close to 0,0 V, showing an interaction of the S atom through bond formation with the surface and through the H atoms bonded to N1 via ion pair formation with the adsorbed Cl- anions. At more negative potentials, the chloride anions leave the electrode surface and the TSC changes to trans-configuration. No faradaic process has been observed as reported in the literature. This result has been confirmed by using the capillary electrophoresis technique. The resonance Raman effect of the TFF has been studied, and the excitation profiles of the bands have been shown as minimum, which indicates an electronic interaction between the two cromophores of the TFF (thiosemicarbazone and ferrocenyl). The theoretic excitation profiles have been calculated by using the transform method, and the results of the obtained adjustment has indicated that there has been a distortion of the ferrocenyl vibrational modes for an electronic transition at 312 nm, assigned to the n-p* of thiosemicarbazone moiety. This result has indicated a great interaction between the two cromophores of TFF. In order to compare the resonance Raman behavior of the TFF with that of the ferrocene, the resonance Raman spectra of the ferrocene have been obtained. It has been verified that the two compounds present an anti-resonant Raman effect, even though the bands have presented very different excitation profiles from those observed in the TFF, which indicates that the incorporation of the thiosemicarbazone group into the ciclopentadienyl has changed the electronic structure of the ferrocenyl group.

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45

Lehmann, Christian Klaus Oliver [Verfasser]. "Plasmonic enhancement in graphene: A resonance Raman study / Christian Klaus Oliver Lehmann." Berlin : Freie Universität Berlin, 2015. http://d-nb.info/107984161X/34.

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46

Li, Wen, and 李闻. "Resonance Raman and time-resolved spectroscopic studies of selected chlorobenzophenone and fluoroquinolones." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48079741.

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Nanosecond time-resolved resonance Raman (ns-TR3) spectroscopy was used in this thesis to study the photoreduction reactions and the photochemistry of chloro-substituted benzophenone (ClBP) triplets. The 3-chlorobenzophenone (3-ClBP), 4-chlorobenzophenone (4-ClBP) and 4,4′-dichlorobenzophenone (4,4′-diClBP) triplets exhibit similar properties to the parent BP triplet. In isopropyl alcohol (IPA), the hydrogen abstraction reactions were observed for the 3-ClBP, 4-ClBP and 4,4′-diDlBP triplets. The diphenylketyl (DPK) radicals produced from the hydrogen abstraction reactions were observed and the recombination of the DPK and dimethylketyl radicals at the para-position was observed to form a light absorption transient (LAT) species. In MeCN:H2O/1:1 aqueous solutions, these DPK radicals were also observed but with a slower formation rate and the LAT species was produced by reaction with OH radicals. Density functional theory (DFT) calculations were employed to help identify the intermediates seen in the TR3 spectra and to help provide information about the vibrational motions of the molecules examined. The 2-Cl-DPK radical was also observed in the TR3 spectra obtained in an IPA solvent. However, the yield of the 2-Cl-DPK radical and the hydrogen abstraction rate was observed to be significantly lower than that of the other ClBP examined here under the same experimental conditions. The results DFT calculations show that the 2-chloro substituent changes the geometry and the electron density of the molecular orbitals of the BP triplet so that the 2-chloro substituent reduces the hydrogen abstraction ability the triplet state, which is different the hypothesis put forward by some previous studies that an electron-withdrawing group should increase the photoreduction ability of BP derivatives. Norfloxacin (NF) and Enoxacin (EN) are representative derivatives of Fluoroquinolones (FQ). There are four forms of NF and EN and these different forms can coexist in aqueous solutions. The UV-vis absorption and resonance Raman (RR) spectra of NF and EN have been obtained in neat acetonitrile (MeCN), MeCN:HClO4-H2O/1:1 (pH?1), MeCN:H2O/1:1 (pH?7.5) and MeCN:NaOH-H2O/1:1 (pH?13) solutions. The species observed in the spectra are assigned by comparison of the experimental spectra to the DFT calculated spectra and the vibrational modes are also described from the results of the DFT calculations. The absorption spectra of NF and EN obtained in MeCN:H2O/1:1 solutions show that some other species coexist with the tautomeric forms in the neutral aqueous solution. The RR spectra of the tautomeric forms of NF and EN were obtained by subtraction of the RR spectra of the neutral and anionic forms from the RR spectra of NF and EN in neutral aqueous solutions. The results suggest that NF and EN exists in neutral, anionic and tautomeric forms in neutral aqueous solutions. The time dependant DFT calculation results suggest that the fluorine atom has little contribution to the lowest unoccupied molecular orbitals of the different forms of NF and EN.
published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy

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47

RodriÌguez, Mendieta IÌnÌƒigo Rafael. "Ultraviolet resonance Raman studies of fast protein dynamics initiated by microsecond mixing." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422020.

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48

Mallinder, Benjamin. "Detection of deoxyribonucleic acid by surface enhanced resonance Raman scattering spectroscopy (SERRS)." Thesis, University of Strathclyde, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248771.

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49

Lehmann, Christian [Verfasser]. "Plasmonic enhancement in graphene: A resonance Raman study / Christian Klaus Oliver Lehmann." Berlin : Freie Universität Berlin, 2015. http://d-nb.info/107984161X/34.

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50

Thibodeau, Daniele L. Carleton University Dissertation Chemistry. "Resonance raman excitation study of monomeric and dimeric chlorophyll a in solution." Ottawa, 1988.

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Dissertations / Theses on the topic 'Raman resonance'

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