Academic literature on the topic 'Molecular spectroscopie'

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Journal articles on the topic "Molecular spectroscopie"

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Leprince, Marine, Lucie Sancey, Jean-Luc Coll, Vincent Motto-Ros, and Benoît Busser. "L’imagerie élémentaire par spectroscopie LIBS." médecine/sciences 35, no. 8-9 (August 2019): 682–88. http://dx.doi.org/10.1051/medsci/2019132.

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L’imagerie multi-élémentaire des tissus biologiques grâce à la spectroscopie LIBS (laser-induced breakdown spectroscopy) permet la visualisation directe de la distribution des éléments endogènes ou exogènes. Cette technologie est notamment utilisée pour mettre en image la cinétique des nanoparticules métalliques dans les organes d’élimination, mais également pour analyser la distribution physiologique des éléments biologiques in situ, et pour révéler la topographie des éléments chimiques, comme les métaux, dans des tissus humains qui ont été exposés à des agents extérieurs potentiellement toxiques. Fondée sur notre expérience et les travaux les plus récents dans le domaine de l’imagerie du contenu élémentaire des tissus animaux et humains, cette revue décrit les principes et les caractéristiques de l’instrumentation LIBS, présente certains aspects techniques pour mettre en place des expériences avec cet outil, montre les avantages et les limites de cette technologie, et s’intéresse aux différentes possibilités qu’offre l’imagerie LIBS pour des applications précliniques et médicales.
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Herzog-Cance, Marie-Hélène, Antoine Potier, and Jacqueline Potier. "Étude, par spectroscopie de vibration, de l'autoprotolyse de l'acide nitrique absolu. Nouvelle interprétation." Canadian Journal of Chemistry 63, no. 7 (July 1, 1985): 1492–501. http://dx.doi.org/10.1139/v85-256.

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The ir and Raman spectra of solid and liquid anhydrous HNO3 have been investigated for the purpose of solving the self-dissociation problem. Identified species are: the oligomer (HNO3), (chains), NO2+ and (NO3•3HNO3)− ions, two monohydrate forms: the ionic pair H2OH+… ONO2− and the molecular association H2O … HONO2, and, finally, some free H3O+ ions.
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Chardon, J. C., and C. Genty. "Transitions induites par deux impulsions — Spectroscopie par transformée de Fourier." Journal de Physique II 3, no. 2 (February 1993): 209–15. http://dx.doi.org/10.1051/jp2:1993123.

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McGuire, Hugo, and Rikard Blunck. "La spectroscopie de fluorescence pour détecter les changements de conformation en canaux unitaires." médecine/sciences 25, no. 11 (November 2009): 951–54. http://dx.doi.org/10.1051/medsci/20092511951.

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Gagné, Jean-Marie, and François Babin. "Effet galvanique et spectroscopie d'ionisation multiphotonique à large bande : application à l'uranium." Journal de Physique II 2, no. 4 (April 1992): 827–37. http://dx.doi.org/10.1051/jp2:1992169.

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Le Coz, G., M. Ben Arfa, G. Sinou, A. Le Nadan, and F. Tuffin. "Etude de l'interaction He* (23S-21S)+H2O. Spectroscopie électronique des électrons éjectés." Journal de Physique II 5, no. 8 (August 1995): 1115–28. http://dx.doi.org/10.1051/jp2:1995172.

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Wilkosz, Natalia, Michał Czaja, Sara Seweryn, Katarzyna Skirlińska-Nosek, Marek Szymonski, Ewelina Lipiec, and Kamila Sofińska. "Molecular Spectroscopic Markers of Abnormal Protein Aggregation." Molecules 25, no. 11 (May 27, 2020): 2498. http://dx.doi.org/10.3390/molecules25112498.

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Abnormal protein aggregation has been intensively studied for over 40 years and broadly discussed in the literature due to its significant role in neurodegenerative diseases etiology. Structural reorganization and conformational changes of the secondary structure upon the aggregation determine aggregation pathways and cytotoxicity of the aggregates, and therefore, numerous analytical techniques are employed for a deep investigation into the secondary structure of abnormal protein aggregates. Molecular spectroscopies, including Raman and infrared ones, are routinely applied in such studies. Recently, the nanoscale spatial resolution of tip-enhanced Raman and infrared nanospectroscopies, as well as the high sensitivity of the surface-enhanced Raman spectroscopy, have brought new insights into our knowledge of abnormal protein aggregation. In this review, we order and summarize all nano- and micro-spectroscopic marker bands related to abnormal aggregation. Each part presents the physical principles of each particular spectroscopic technique listed above and a concise description of all spectral markers detected with these techniques in the spectra of neurodegenerative proteins and their model systems. Finally, a section concerning the application of multivariate data analysis for extraction of the spectral marker bands is included.
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Ha, Tran, Arnaud Cuisset, Sébastien Payan, Martin Schwell, Yao Té, Linda Tomasini, and Yannick Giraud Héraud. "The first Vietnam School of Earth Observation: Atmospheric Remote Sensing and Molecular Spectroscopy." VIETNAM JOURNAL OF EARTH SCIENCES 41, no. 2 (March 15, 2019): 138–55. http://dx.doi.org/10.15625/0866-7187/41/2/13724.

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In this review paper, we give an introduction to molecular spectroscopy and its relation to atmospheric remote sensing and examples of recent developments in spectroscopic experimental techniques and modelling. Atmospheric retrieval techniques, based on radiative transfer theories and molecular spectroscopy as well as some atmospheric remote sensing missions using spectroscopic techniques are presented.
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Silveira, Célia M., Lidia Zuccarello, Catarina Barbosa, Giorgio Caserta, Ingo Zebger, Peter Hildebrandt, and Smilja Todorovic. "Molecular Details on Multiple Cofactor Containing Redox Metalloproteins Revealed by Infrared and Resonance Raman Spectroscopies." Molecules 26, no. 16 (August 11, 2021): 4852. http://dx.doi.org/10.3390/molecules26164852.

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Vibrational spectroscopy and in particular, resonance Raman (RR) spectroscopy, can provide molecular details on metalloproteins containing multiple cofactors, which are often challenging for other spectroscopies. Due to distinct spectroscopic fingerprints, RR spectroscopy has a unique capacity to monitor simultaneously and independently different metal cofactors that can have particular roles in metalloproteins. These include e.g., (i) different types of hemes, for instance hemes c, a and a3 in caa3-type oxygen reductases, (ii) distinct spin populations, such as electron transfer (ET) low-spin (LS) and catalytic high-spin (HS) hemes in nitrite reductases, (iii) different types of Fe-S clusters, such as 3Fe-4S and 4Fe-4S centers in di-cluster ferredoxins, and (iv) bi-metallic center and ET Fe-S clusters in hydrogenases. IR spectroscopy can provide unmatched molecular details on specific enzymes like hydrogenases that possess catalytic centers coordinated by CO and CN− ligands, which exhibit spectrally well separated IR bands. This article reviews the work on metalloproteins for which vibrational spectroscopy has ensured advances in understanding structural and mechanistic properties, including multiple heme-containing proteins, such as nitrite reductases that house a notable total of 28 hemes in a functional unit, respiratory chain complexes, and hydrogenases that carry out the most fundamental functions in cells.
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Hochstaffl, Philipp, Franz Schreier, Manfred Birk, Georg Wagner, Dietrich G. Feist, Justus Notholt, Ralf Sussmann, and Yao Té. "Impact of Molecular Spectroscopy on Carbon Monoxide Abundances from TROPOMI." Remote Sensing 12, no. 21 (October 23, 2020): 3486. http://dx.doi.org/10.3390/rs12213486.

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The impact of SEOM–IAS (Scientific Exploitation of Operational Missions–Improved Atmospheric Spectroscopy) spectroscopic information on CO columns from TROPOMI (Tropospheric Monitoring Instrument) shortwave infrared (SWIR) observations was examined. HITRAN 2016 (High Resolution Transmission) and GEISA 2015 (Gestion et Etude des Informations Spectroscopiques Atmosphériques 2015) were used as a reference upon which the spectral fitting residuals, retrieval errors and inferred quantities were assessed. It was found that SEOM–IAS significantly improves the quality of the CO retrieval by reducing the residuals to TROPOMI observations. The magnitude of the impact is dependent on the climatological region and spectroscopic reference used. The difference in the CO columns was found to be rather small, although discrepancies reveal, for selected scenes, in particular, for observations with elevated molecular concentrations. A brief comparison to Total Column Carbon Observing Network (TCCON) and Network for the Detection of Atmospheric Composition Change (NDACC) also demonstrated that both spectroscopies cause similar columns; however, the smaller retrieval errors in the SEOM with Speed-Dependent Rautian and line-Mixing (SDRM) inferred CO turned out to be beneficial in the comparison of post-processed mole fractions with ground-based references.
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Dissertations / Theses on the topic "Molecular spectroscopie"

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Kaszub, Wawrzyniec. "Photo-induced phase transitions in molecular materials." Rennes 1, 2012. http://www.theses.fr/2012REN1S030.

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The main purpose of this Ph. D. Thesis is to study the photo-induced transformations by a laser pulse in molecular materials. The results have been obtained thanks the use of pump-probe optical techniques. This required innovative experimental developments, including first attempts with a single shot technique. In the spincrosover family of molecular materials, in which light may induce the switching from a non magnetic to a magnetic state, for the first time we followed the transformation dynamics over ten decades in time scale, from 100 femtoseconds to a millisecond. It reveals that the process follows a complex pathway from molecular to material scale through a sequence of steps. A charge transfer organic compound, which exhibits an insulatior-to-metal phase transition, has also been investigated. A dynamics implying several coherent optical phonon modes has been clearly observed. The behaviour as a function of laser pulse intensity and temperature shows that the state photo-induced from the insulating phase differs from the metallic phase at thermal equilibrium. The newly developed single shot set-up proved able of recording changes upon an irreversible transformation, for instance inside a hysteresis regime. This set has been tested by observing photo-induced damages of a thin gold layer
L'objectif principal de ce travail de thèse de doctorat est l'étude de transformations photo-induites par un pulse laser dans des matériaux moléculaires. Les résultats ont été obtenus grâce à l'utilisation de techniques optiques pompe-sonde. Ceci a nécessité des développements expérimentaux innovants, incluant des premières tentatives de techniques « single shot ». Dans un matériau à transition de spin, où la lumière peut induire la commutation d'un état non magnétique à un état magnétique, nous avons pu suivre pour la première fois la dynamique de la transformation sur plusieurs ordres de grandeurs en temps, de 100 femtosesecondes à la milliseconde. Ceci a permis de montrer que le processus se produit en plusieurs étapes successives, de l'échelle de la molécule à celle du matériau. Un composé organique à transfert de charge, qui présente une transition métal-isolant, a aussi été étudié. Une dynamique mettant en jeu plusieurs modes de phonons optiques cohérents a clairement été observée. Le comportement en fonction de l'intensité du pulse laser et de la température permet de conclure que l'état photo-induit à partir de la phase isolant diffère de la phase métallique observée à l'équilibre thermique. La mise en place du nouveau montage optique « single shot » va permettre d'observer des changements d'état irréversible, comme dans un régime d'hystérèse. Ce montage a été testé en observant le comportement non thermique d'une couche mince d'or
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Gromova, Olga. "High resolution molecular spectroscopy of the sulfur-containing XY2 type molecules." Dijon, 2010. http://www.theses.fr/2010DIJOS090.

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Dans cette thèse, nous avons effectué des spectres d'absorption à haute résolution de H2S, D2S, HDS et SO2 enregistrés pour la première fois ou avec une meilleure précision expérimentale que les spectres antérieurs. Nous avons développé une méthode originale de "global fitting" qui nous a permis l'analyse de 22 bandes vibrationnelles soit un total de 9700 transitions rovibrationnelles pour la molécule de D2S. Nous avons appliqué cette méthode à des molécules de symétrie CS, en particulier tout le spectre rovibrationnel de la molécule HDS a été analysé. La méthode SPGF est appliquée aux molécules triatomiques H2S, D2S, HDS. Une procédure originale permettant l'identification des bandes très peu intenses a été mise au point pour la première fois et appliquée aux bandes chaudes de la molécule SO2. Le formalisme U(p+1) est adapté aux molécules triatomiques non linéaires de symétrie C2v et les paramètres d'un Hamiltonien vibrationnel sont déterminés dans le cas de la molécule D2S
In this thesis, we analyzed the high resolution absorption molecular spectra of H2S, D2S, HDS and SO2 registered for the first time or with better experimental characteristics as compared with those registered before. For the first time in the practice of rotation-vibrational spectroscopy in the frame of the developed method of "global fitting" the analysis of 22 bands (as a whole more than 9700 rotation-vibrational lines) of D2S molecule is realized. This method of "global fitting" is developed with regard to molecules of Cs symmetry ; on this basis a simultaneous analysis of all the known up to the present rotation-vibrational spectra of HDS molecule is realized. The SPGF method is applied to the three-atom molecules H2S, D2S, HDS. An original procedure of the identification of very weak lines is developed for the first time and practically realized for the example of "hot" lines of SO2 molecule. U(p+1) formalism is adapted to the three-atom non-linear molecules of C2v symmetry and the parameters of a vibrational Hamiltonian is developed in the case of the D2S molecule
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Burkart, Johannes. "Optical feedback frequency-stabilized cavity ring-down spectroscopy - Highly coherent near-infrared laser sources and metrological applications in molecular absorption spectroscopy." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAY045/document.

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La spectroscopie d'absorption moléculaire est un outil incontournable non seulement pour la physique fondamentale et la métrolgie mais aussi pour des domaines aussi divers que les sciences environnementales, la planétologie ou l'astrophysique. Ces dernières années, des techniques spectroscopiques qui exploitent l'amplification résonnante d'interaction entre lumière laser et molécules dans une cavité optique ont fourni des détectivités exceptionnelles sur l'axe d'absorption, tandis que l'axe de fréquence des spectromètres n'atteignait généralement pas le même niveau de précision.Dans cette thèse, nous avons répondu à ce défi en développant la spectroscopie en cavité par temps de déclin stabilisée en fréquence par rétroaction optique (OFFS-CRDS en anglais). Cette nouvelle technique présente une combinaison unique de stabilité et résolution fréquentielles sub-kHz, d'un niveau d'intensité lumineuse intra-cavité de l'ordre du kW/cm^2, d'une detectivite de 2 x 10^(−13) cm^(−1)Hz^(-1/2) limitée par le bruit de photons, et d'une limite de détection de 8.4 x 10^(−14) cm^(−1) sur une plage spectrale étroite. Ces performances inédites sont dues à l'asservissement de la cavité spectroscopique à un laser balayé en fréquence par modulation à bande latérale unique et stabilisé par rétroaction optique avec une cavité en V de réference ultrastable. Pour transférer la cohérence de ce laser sub-kHz à des lasers plus bruiteux dans d'autres gammes spectrales à travers un peigne de fréquence optique, nous avons exploré une nouvelle méthode de clonage de phase par une correction anticipative à large bande passante et démontré une erreur résiduelle de phase de 113 mrad. En appliquant l'OFFS-CRDS à la spectroscopie du CO2 à 1.6 μm, nous avons obtenu un spectre large bande avec une dynamique de 8 x 10^5, et nous avons déterminé douze fréquences de transition absolues avec une exactitude de l'ordre du kHz en mesurant des Lamb dips sub-Doppler en absorption saturée avec un dispositif équipé d'un peigne de fréquence. Par ailleurs, nous avons procédé à une analyse détaillée des sources d'erreurs systematiques en CRDS et nous avons déduit une formule analytique pour le déclin de cavité non-exponentiel dans un régime faiblement saturé qui est susceptible de contribuer à de futures mesures de moments de transition dipolaire indépendantes de la concentration. Nos résultats ouvrent des perspectives prometteuses pour des applications métrologiques de l'OFFS-CRDS, comme par exemple l'étude de profils de raie poussés, la mesures de rapports isotopiques et la spectroscopie d'absorption saturée extensive dans le proche infrarouge
High-precision molecular absorption spectroscopy is a powerful tool for fundamental physics and metrology, as well as for a broad range of applications in fields such as environmental sciences, planetology and astrophysics. In recent years, spectroscopic techniques based on the enhanced interaction of laser light with molecular samples in high-finesse optical cavities have provided outstanding detection sensitivities on the absorption axis, while the spectrometer frequency axis rarely met as high precision standards.In this thesis, we addressed this challenge by the development of Optical Feedback Frequency-Stabilized Cavity Ring-Down Spectroscopy (OFFS-CRDS). This novel technique features a unique combination of sub-kHz frequency resolution and stability, kW/cm^2-level intracavity light intensity, a shot-noise limited absorption detectivity down to 2 x 10^(−13) cm^(−1)Hz^(-1/2), as well as a detection limit of 8.4 x 10^(−14) cm^(−1) on a narrow spectral interval. This unprecedented performance is based on the tight Pound-Drever-Hall lock of the ring-down cavity to a single-sideband-tuned distributed-feedback diode laser which is optical-feedback-stabilized to a highly stable V-shaped reference cavity. To transfer the coherence of this sub-kHz laser source to noisier lasers in other spectral regions through an optical frequency comb, we have explored a novel high-bandwidth feed-forward phase cloning scheme and demonstrated a residual phase error as low as 113 mrad. Applying OFFS-CRDS to the spectroscopy of CO_2 near 1.6 μm, we obtained a broadband spectrum with a dynamic range of 8 x 10^5 and retrieved twelve absolute transition frequencies with kHz-accuracy by measuring sub-Doppler saturated absorption Lamb dips with a comb-assisted setup. Furthermore, we have performed a comprehensive analysis of systematic error sources in CRDS and derived an analytic formula for the non-exponential ring-down signal in a weakly saturated regime, which may contribute towards future concentration-independent transition dipole moment measurements. Our results open up promising perspectives for metrological applications of OFFS-CRDS, such as advanced absorption lineshape studies, isotopic ratio measurements and extensive saturated absorption spectroscopy in the near infrared
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Gromova, O. V. "High resolution molecular spectroscopy of the sulfur-containing XY2 type molecules." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00534459.

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Dans cette these, nous avons effectue l'analyse des spectres d'absorption a haute resolution de H2S, D2S, HDS et SO2 enregistres pour la premiere fois ou avec une meilleure precision experimentale que les spectres anterieurs. Nous avons developpe une methode originale de "global ftting" qui nous a permis l'analyse de 22 bandes vibrationnelles soit un total de 9700 transitions rovibrationnelles pour la molecule de D2S. Nous avons applique cette meme methode a des molecules de symmetrie Cs, en particulier tout le spectre rovibrationnel de la molecule HDS a ete analyse. La methode SPGF est appliquee aux molecules triatomiques H2S, D2S, HDS. Une procedure originale permettant l'identication des bandes tres peu intenses a ete mise au point pour la premiere fois et appliquee aux bandes chaudes de la molecule SO2. Le formalisme U(p+1) est adapte aux molecules triatomiques non lineaires de symmetrie C2v et les parametres d'un Hamiltonien vibrationnel sont determines dans le cas de la molecule D2S.
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Grenier, Benjamin. "Spectroscopie théorique : description des effets de la température sur les paramètres de résonance magnétique nucléaire." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0494/document.

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- Notre objectif est de pouvoir définir une méthodologie théorique qui permet de simuler les spectres de Résonance Magnétique Nucléaire (RMN) en prenant en compte les effets de la température, afin de proposer une aide à l’interprétation des résultats expérimentaux plus pertinente.- Pour traiter la description des effets de la température sur les paramètres de RMN, nous avons étudiés les azacalixarènes, qui sont des oligomères cycliques d’unités phénol reliées entre elles par des ponts azotés. Ces molécules ont une forme de calice d’où leur nom de azacalixarènes. Par cette cavité ces molécules peuvent capter différents types de composés et sont utilisées dans le domaine de la chimie hôte-invité.- Une grande variété de substituants peut être fixée sur ces azacalixarènes. Expérimentalement on peut suivre facilement les effets des variations de structures au niveau des propriétés physico-chimiques par la RMN.- C’est pourquoi, dans un premier temps, nous nous avons étudié la description géométrique des azacalixarènes en fonction de différents substituants et de différentes isoméries à l’aide de la théorie de la fonctionnelle de la densité, donc sans prise en compte de la température. - Enfin, nous avons simulé les paramètres de RMN de ces systèmes en utilisant la Théorie de la Fonctionnelle de la Densité. Ceci pour calculer le spectre RMN des azacalixarènes à l’état fondamental.- Enfin, en effectuant des simulations de dynamique moléculaire, en utilisant la Mécanique Moléculaire, nous avons pu prendre en compte les effets de la température. Nous avons pu simuler les paramètres de RMN de ces systèmes en prenant désormais en compte les effets de la température
- Our objective is to define a theoretical methodology, which allows to simulate the Nuclear Magnetic Resonance (NMR) spectra taking into account the temperature effects, in order to propose a help to the interpretation of the more relevant experimental results.- To deal with the description of the temperature effects on the NMR parameters, we have studied azacalixarenes, which are cyclic oligomers of phenol units linked together by nitrogen bridges. These molecules have a calyx shape, hence their name azacalixarenes. By this cavity these molecules can capture different types of compounds and are used in the host-guest chemistry field.- A wide variety of substituents can be attached to these azacalixarenes. Experimentally, one can easily follow the structure variations effects, at the level of physicochemical properties by NMR.- For this reason, we first investigated the geometric description of azacalixarenes as a function of different substituents and different isomers using the Density Functional Theory, so without taking into account the temperature. - Then, we simulated the NMR parameters of these systems using the Density Functional Theory. This is to calculate the azacalixarenes NMR spectrum in the ground state.- FInally, by performing molecular dynamics simulations using Molecular Mechanics, we were able to take into account the temperature effects. We were able to simulate the NMR parameters of these systems taking now into account the effects of temperature
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Angelova, Gergana. "Dissociative recombination of hydrocarbon and other molecular ions." Rennes 1, 2005. http://www.theses.fr/2005REN1S023.

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Dans cette thèse, la recombinaison dissociative des ions moléculaires poly atomiques a été étudiée en utilisant l'anneau de stockage ASTRID à l'Université d'Aarhus, Danemark et de l'appareillage débordant de post décharge en écoulement avec spectromètre de masse et de sonde de Langmuir (FALP-MS) à l'Université de Rennes 1, France. Des rapports de branchement de recombinaison dissociative pour les ion hydricarbures avec trois et quatre atoms de carbon sont rapportés et des formes isomériques possibles des ions à l'étude sont discutées. La recombinaison dissociative dion de tetrafluoromethane à été étudiée en utilisant la technique de post décharge en écoulement avec spetromètre de masse et de sonde de Langmuir (FALP-MS) et le coefficient de recombinaison mesuré (300K) est rapporté. Cette thèse se compose d'une brève introduction et d'une description des deux tehniques employées pour exécuter les expériences, une discussion des résultat expérimentaux et des conclusions
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Kumar, Vishant. "Fragmentation dynamics and geometrical arrangement of diatomic molecular clusters." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMC245.

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L'analyse d'une expérience cinématiquement complète de collision ion-agrégats permet d'accéder à la dynamique de la dissociation des agrégats ionisés. Les cibles en phase gazeuse permettent d'étudier l'agrégat dans un environnement simple et de déterminer ses propriétés intrinsèques - en dehors de l'état condensé. De petits agrégats van der Waals de N2 et CO sont produits dans l'expansion supersonique d'un jet gazeux et irradiés par un faisceau d'ions multichargés de basse énergie produit par l'installation ARIBE/GANIL. Grâce à notre dispositif expérimental COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy), il est possible de mesurer en coïncidence les vecteurs d'impulsion 3D des fragments chargés résultant de la collision. Nous avons effectué une expérience pour étudier la dynamique de fragmentation et la géométrie des dimères et trimères de N2 et CO en utilisant un faisceau projectile Ar9+ à une énergie de 15 qkeV. Suite à une multiple capture électronique, la cible subit une dissociation en deux ou trois corps. Pour les voies à trois corps, deux processus distincts ont été identifiés dans lesquels les liaisons van der Waals et covalente se rompent simultanément ou séquentiellement. De plus, la technique d'imagerie par explosion coulombienne a été utilisée pour déterminer la structure tridimensionnelle des dimères moléculaires N2 et CO et des trimères. Nous avons observé que les molécules de N2 et CO sont orientés perpendiculairement à l'axe du dimer dans une configuration planaire (H) ou non-planaire (X) et que les trimères (N2)3 et (CO)3 présentent une géométrie en forme de triangle équilatéral
The analysis of a kinematically complete ion-cluster collision experiment provides insight in the dynamics of the ionized cluster dissociation. The gas phase targets allow to study the cluster in a simple environment and to determine their intrinsic properties for further condensed states. Small van der Waals clusters of N2 and CO are produced in the supersonic expansion of a gas jet and irradiated by a low energy highly charged ion beam produced by the ARIBE/GANIL facility. Using our experimental set-up COLTRIMS (COLd Target Recoil Ion Momentum Spectroscopy) it is made possible to measure in coincidence the 3-D momentum vectors of the charged fragments resulting from the collision. We have performed experiment to investigate the fragmentation dynamics and geometry of N2 and CO dimers and trimers using a projectile beam Ar9+ with the 15 qkeV energy. Following multiple electron capture, the target undergoes two or three body dissociation. For three body channels, two distinct processes have been identified in which the van der Waals and covalent bond breaks either simultaneously or sequentially. Additionally, the Coulomb explosion imaging technique has been used to determine the three dimensional structure of the N2 and CO molecular dimers and trimers. We found that the N2 and CO molecules sit perpendicularly to the dimer axis in a planar (H) or non-planar (X) configuration and that (N2)3 and (CO)3 trimers exhibit an equilateral triangular geometry
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Tran, Vu. "Towards High Precision Spectroscopy of Hydrogen Molecular Ions H2+ and HD+ : theory and experiment." Paris 6, 2013. http://www.theses.fr/2013PA066621.

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This thesis is devoted to the theoretical and experimental study of high precision spectroscopy in the hydrogen molecular ion H+2 and HD+. The main objective of these researches is to provide a stringent test of molecular quantum electrodynamics (QED) calculations, and obtain an improved determination of the ratio of the proton and electron masses mp~me. After a general introduction in chapter 1, the chapter 2 of this thesis explains how to produce state-selected H2+ ions using resonance-enhanced multiphoton ionization (REMPI) method and describes the designs of a new ion source. The theoretical calculations show that at least 87% of the ions H2+ produced by (3+1) REMPI method via intermediate C1piu v=0;L=2 of H2 are in the rovibrational state v=0;L+=2. This new ion source is very important to increase the signal-to-noise ratio in H2+ spectroscopy. The experimental part describes the setup of a new laser system at 303 nm to perform the photoionization, and the design of a system to transfer H2+ ions into a linear Paul trap. Chapter 3 of thesis is a theoretical study of the feasibility of quasi-degenerate twophoton spectroscopy of HD+ ion in the Lamb-Dicke regime. This work provides a new method to overcome the Doppler-broadening that occurs in single-photon spectroscopy. With the proposed method, the first-order Doppler shift is completely suppressed and an accuracy level at 10?14 is possible
Cette thèse est consacrée à l'étude théorique et expérimentale de la spectroscopie à haute résolution des ions hydrogène moléculaire H2+ et HD+. L'objectif principale de ces recherches est de tester les calculs d'électrodynamique quantique (QED) dans le domaine moléculaire, et d'obtenir une nouvelle détermination du rapport des masses du proton et de l'électron mp/me. Après une mise en perspective au chapitre 1, le chapitre 2 de la thèse explique comment produire des ions H2+ sélectionnés en état interne par photodissociation multiphotonique résonante et décrit les dispositifs expérimentaux nécessaires pour faire cette expérience. La partie théorique montre que les ions produits par REMPI à 3+1 photons via l'état intermédiaire C1piu v=0;L=2 de H2 sont au moins 87% dans l'état v=0;L+= 2. Cette nouvelle source d'ions sélectionnés en état interne est très importante pour augmenter le rapport signal sur bruit de la spectroscopie de H2+. La partie exprimentale décrit la mise en oeuvre d'un laser à 303 nm pour effectuer la photodissociation et aussi la conception du système d'optique ionique pour transférer les ions dans un piège de Paul quadrupolaire. Le chapitre 3 de la thèse est une étude théorique sur la faisabilité de la spectroscopie de HD+ sans effet Doppler avec deux photons presque dégénérés, dans le régime de Lamb-Dicke. Ce travail fournit un moyen d'améliorer la spectroscopie à un photon de HD+ qui est aujourd'hui limitée par l'élargissement Doppler. Avec la méthode proposée, l'élargissement Doppler du premier ordre est supprimé complètement et nous montrons que les mesures peuvent atteindre le niveau de précision de 10^-14
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Richter, Philipp. "FUV absorption spectroscopy of interstellar molecular hydrogen towards the Magellanic clouds /." Aachen : Shaker, 1999. http://catalogue.bnf.fr/ark:/12148/cb37739235j.

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Dissertation--Mathematisch-Naturwissenschaftliche Fakultät--Bonn--Rheinische Friedrich-Wilhelms-Universität, 1999. Titre de soutenance : FUV spectroscopy of interstellar molecular hydrogen towards the Magellanic clouds.
FUV = far ultraviolet. Bibliogr. p. 83-85.
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Schneider, Julia. "Characterisation of Single and Multibubble Cavitation Through Analysis of Molecular, Atomic and Ionic Line Emissions." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20011.

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La cavitation acoustique (formation, croissance et effondrement de bulles de gaz dans un liquide soumis aux ultrasons) est à l'origine de réactions chimiques (sonochimie) via la génération de conditions extrêmes lors de l'effondrement des bulles. Des températures de 103-104K et des pressions de l'ordre de 1000 atm sont atteintes au cœur des bulles [1]. Dans ces conditions, les liaisons chimiques des molécules volatiles présentes dans les bulles peuvent être rompues, formant, dans le cas de solutions aqueuses, des radicaux OH et H. Par ailleurs, l'effondrement violent des bulles de cavitation peut être accompagné par l'émission de lumière, sonoluminescence (SL), qui est le sujet d'étude de ce travail. Cette émission lumineuse est formée d'un continuum, de l'UV au proche IR, similaire à l'émission d'un corps noir, sur lequel peuvent se superposer des lignes d'émission atomiques ou moléculaires.On distingue deux types de SL: la SL mono-bulle (SBSL) et la SL multibulle (MBSL). En général, les spectres de MBSL se différencient de ceux de SBSL par la présence de lignes d'émission (d'atomes alcalins, de radicaux hydroxy… [2]), si bien que les mécanismes d'émission ainsi que la nature des conditions à l'intérieur des bulles lors de leur effondrement ont longtemps été considérés comme différents pour les systèmes mono- et multi-bulles. Un pont a été érigé entre les deux systèmes par le travail de Liang et al. [3] qui mit en évidence les conditions expérimentales permettant l'apparition de lignes dans le spectre de SBSL. Dans ce contexte, l'objectif de ce travail était de comparer les émissions de SBSL (27 kHz) et MBSL à haute et basse fréquences (20, 203, 607 kHz) pour différentes solutions aqueuses. Un sonoréacteur monobulle a été développé, dans lequel la température, la nature et la pression de gaz dissous ainsi que la pression acoustique sont contrôlés. Les électrolytes étudiés étaient : NaCl et les chlorures de lanthanides luminescents Ce3+, Tb3+, Eu3+ et Gd3+. Ces derniers peuvent être excités soit par absorption de photons dans l'UV soit par collisions avec des particules énergétiques [4].Dans la première partie de ce travail, les conditions à l'intérieur d'une monobulle lors de son effondrement ont été estimées via un fit du continuum par l'équation de Planck du corps noir. Les températures du corps noir obtenues sont de l'ordre de 104K, en accord avec des études précédentes. Elles sont indépendantes de la présence de NaCl et de la pression acoustique alors que l'intensité de SL y est très sensible. Les résultats obtenus remettent en question l'utilisation du modèle du corps noir en SL. Des lignes d'émission atomique et moléculaire se superposent parfois au continuum de SL : en MBSL, et en SBSL dans certaines conditions particulières (pression d'argon suffisante, faible pression acoustique) [3, 5]. Ce travail met en évidence la similarité entre la forme de l'émission de OH en SBSL et en MBSL à 20kHz, ce qui indique des conditions intrabulles très proches dans les conditions expérimentales étudiées [6]. En SBSL sous 70mbar d'Ar, l'intensité des lignes diminue lorsque la pression acoustique augmente, jusqu'à leur disparition dans le continuum. Cette évolution peut apparaître comme un lien entre SBSL et MBSL.Par ailleurs, cette étude confirme que la concentration en sodium à l'interface bulle-liquide, qui peut être enrichie par l'utilisation d'un contre-ion tensioactif, est le paramètre clé de l'observation de l'émission du sodium en SBSL, suggérant que l'excitation du sodium a lieu soit à l'interface de la bulle, soit en son cœur, après injection de gouttelettes. La seconde partie de cette étude concerne l'effet de la fréquence ultrasonore et de la puissance acoustique sur l'intensité de luminescence des ions lanthanides en MBSL. La luminescence des ions Tb3+, Ce3+ et Eu3+ est ainsi observée. La comparaison des rendements de SL et de photoluminescence indique qu'à l'exception de Ce3+, l'excitation par photons est min
The importance of acoustic cavitation, i.e., the formation, growth and collapse of gaseous cavities in liquid exposed to ultrasound, in sonochemistry is based on the generation of extreme conditions upon bubble collapse. Temperatures and pressures inside the collapsing bubble are approximated to reach 104 K and 1000 atm, respectively [suslick-1999]. Under such conditions chemical bonds of the solvent vapour or volatile solutes present in the bubble core are easily cleaved, which in the case of aqueous systems, leads to the formation of chemically reactive OH and H radicals. These primary radicals either recombine leading to chemiluminescence, or diffuse into solution, where they are liable to react with other species. Of particular importance in this work is the light emission that accompanies cavitation, termed sonoluminescence (SL). This emission is a broad continuum ranging from 200nm to 900 nm, resembling the emission of a blackbody, which can be superimposed with atomic or molecular emission lines comparable to bremsstrahlung. It is necessary to distinguish two forms of SL, single-bubble (SBSL) and multibubble (MBSL). In general, MBSL spectra differ from SBSL spectra in that they contain emission lines, e.g., from alkali atoms or hydroxyl radicals [matula-1995]. Consequently, it was, until recently considered that the mechanisms of light emission, and the nature of the bubble interior upon collapse were fundamentally different for the single and multibubble systems. Considering that MBSL is a cloud of single bubbles a bridging theory is desired.With this background the objective of the present work was to conduct a comparative spectroscopic analysis of SBSL, driven at 27 kHz, and MBSL generated from low and high ultrasonic frequencies (20, 203 and 607 kHz) of aqueous electrolyte solutions. Therefore a single bubble sonoreactor was developed, where the temperature, gas content and type, as well as the acoustic pressure could be controlled. The electrolytes of choice were: sodium chloride and chlorides of the luminescent lanthanide ions, Ce3+, Tb3+, Eu3+ and Gd3+, which can be excited by UV light absorption and collisions with energetic particles [kulmala-1995]. In the first part of this work the conditions upon bubble collapse were approximated by fitting the broad-band continuum of SBSL spectra of water with 70 mbar of argon and a 0.5 M NaCl solution with 70 mbar of argon using Planck's law of blackbody radiation. The obtained blackbody temperatures are in the range of 104 K, which is in good agreement with previous studies, but with the discrepancy of being independent of the presence of NaCl and the acoustic pressure, whereas the SL intensity increased by a factor of more than 10 upon increased acoustic pressure. The different trends followed by SL intensity and blackbody temperatures question the blackbody model. Another observation questioning the blackbody model is the appearance of atomic and molecular emission lines in MBSL and as recently observed also in SBSL [liang-2007, young-2001]. The present work proofed that the key factors for line emission in SBSL are small amounts of argon and low acoustic pressure. Moreover, the work revealed that the shape of the OH• radical emission is very similar to that in MBSL spectra, indicating the strong similarity of intrabubble conditions in MBSL and SBSL under certain experimental conditions [schneider-2011]. An increase of the acoustic pressure caused the continuum to overlap the lines until they become indistinguishable giving the usually in SBSL observed featureless continuum. This advance is a big step toward bridging the gap between SBSL and MBSL. Furthermore this study reveals that the concentration of the sodium ion at the interface of a single bubble can be enriched with a surface active counterion and the concentration is crucial for the observation of the sodium line in SBSL, suggesting that excitation of sodium either takes place at the interface of the
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Books on the topic "Molecular spectroscopie"

1

M, Mirabella Francis, ed. Modern techniques in applied molecular spectroscopy. New York: Wiley, 1998.

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1927-, Rashba Ė I., and Sheka E. F, eds. Spectroscopy of molecular excitons. Berlin: Springer-Verlag, 1985.

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1950-, Scott P. R., ed. Structure and spectra of molecules. Chichester [West Sussex]: Wiley, 1985.

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Molecular spectra and molecular structure. 2nd ed. Malabar, Fla: R.E. Krieger Pub. Co., 1989.

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1961-, McCash Elaine M., ed. Fundamentals of molecular spectroscopy. 4th ed. London: McGraw-Hill, 1994.

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Colloquium on High Resolution Molecular Spectroscopy (12th 1991 Dijon). Douzieme colloque sur la spectroscopie moleculaire a haute resolution =: Twelfth Colloquium on High Resolution Molecular Spectroscopy. Dijon: Presses de l'Universite de Bourgogne, 1991.

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Ch, Jungen, ed. Molecular applications of quantum defect theory. Philadelphia, PA: Institute of Physics Pub., 1996.

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Wendisch, Detlef A. W. Acronyms and abbreviations in molecular spectroscopy: An enzyclopedic dictionary. Berlin: Springer-Verlag, 1990.

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1949-, Endō Y., ed. High-resolution spectroscopy of transient molecules. Berlin: Springer-Verlag, 1985.

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Sneddon, Joseph. Advances in atomic spectroscopy. Greenwich, Conn: JAI Press, 1995.

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Book chapters on the topic "Molecular spectroscopie"

1

Schrader, Bernhard. "The Symmetry of Molecules and Molecular Vibrations." In Low Temperature Molecular Spectroscopy, 435–75. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0281-7_17.

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Bruder, Lukas, Markus Koch, Marcel Mudrich, and Frank Stienkemeier. "Ultrafast Dynamics in Helium Droplets." In Topics in Applied Physics, 447–511. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94896-2_10.

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Abstract Helium nanodroplets are peculiar systems, as condensed superfluid entities on the nanoscale, and as vessels for studies of molecules and molecular aggregates and their quantum properties at very low temperature. For both aspects, the dynamics upon the interaction with light is fundamental for understanding the properties of the systems. In this chapter we focus on time-resolved experiments in order to study ultrafast dynamics in neat as well as doped helium nanodroplets. Recent experimental approaches are reviewed, ranging from time-correlated photon detection to femtosecond pump-probe photoelectron and photoion spectroscopy, coherent multidimensional spectroscopy as well as applications of strong laser fields and novel, extreme ultraviolet light sources. The experiments examined in more detail investigate the dynamics of atomic and molecular dopants, including coherent wave packet dynamics and long-lived vibrational coherences of molecules attached to and immersed inside helium droplets. Furthermore, the dynamics of highly-excited helium droplets including interatomic Coulombic decay and nanoplasma states are discussed. Finally, an outlook concludes on the perspectives of time-resolved experiments with helium droplets, including recent options provided by new radiation sources of femto- or even attosecond laser pulses up to the soft X-ray range.
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Zhu, He, and Peter B. Barker. "MR Spectroscopy and Spectroscopic Imaging of the Brain." In Methods in Molecular Biology, 203–26. Totowa, NJ: Humana Press, 2010. http://dx.doi.org/10.1007/978-1-61737-992-5_9.

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Hertel, Ingolf V., and Claus-Peter Schulz. "Molecular Spectroscopy." In Atoms, Molecules and Optical Physics 2, 289–381. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-642-54313-5_5.

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Battaglia, Franco, and Thomas F. George. "Molecular Spectroscopy." In Fundamentals in Chemical Physics, 183–219. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-1636-9_5.

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Giesen, Thomas, Corey A. Rice, John P. Maier, Yvain Carpentier, Gaël Rouillé, Mathias Steglich, Cornelia Jäger, et al. "Molecular Spectroscopy." In Laboratory Astrochemistry, 13–108. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2014. http://dx.doi.org/10.1002/9783527653133.ch2.

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Crabb, N. C., and P. W. B. King. "Molecular spectroscopy." In Process Analytical Chemistry, 183–216. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0591-0_6.

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Marcelino, Agúndez. "Molecular Spectroscopy." In Encyclopedia of Astrobiology, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-642-27833-4_5132-1.

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Carrington, Alan, and G. Porter. "Molecular spectroscopy." In 100 Years of Physical Chemistry, 35–46. Cambridge: Royal Society of Chemistry, 2007. http://dx.doi.org/10.1039/9781847550002-00035.

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Herbst, Eric. "I. Molecules in Space and Molecular Spectroscopy." In Millimeter-Wave Astronomy: Molecular Chemistry & Physics in Space, 329–39. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4714-9_20.

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Conference papers on the topic "Molecular spectroscopie"

1

Rakestraw, David J. "Applications of Infrared Spectroscopy for Combustion Diagnostics." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/lacea.1996.lthc.1.

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The application of infrared spectroscopies for combustion diagnostics offers an exciting new opportunity to measure a wide range of polyatomic molecular species. The ability to measure low concentrations of many species important in combustion chemistry has been limited to a great extent to molecules that that can be probed using laser-induced fluorescence in the visible and ultraviolet spectral regions. Over the past several years our group has been investigating the use of infrared spectroscopies in an effort to greatly expand the polyatomic molecules that can be probed using laser diagnostics. This effort has benefited from advances in laser technology as well as the development of new spectroscopic approaches. The work discussed in this paper makes use of a tunable single-mode optical parametric oscillator system to provide high resolution rovibrational spectra. Degenerate four-wave mixing (DFWM) and cavity ringdown laser absorption spectroscopy (CRLAS) are the two spectroscopic techniques investigated.
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Hojer, S., H. Ahlberg, S. Lundqvist, J. Davidsson, and L. Holmlid. "IR Tunable Diode Laser Absorption Spectroscopy in an no Seeded Molecular Beam." In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.tha4.

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In many experiments involving molecular beams for fundamental studies of e.g. chemical reactions in crossed beams [1,2], so called seeded beams are used. In such a beam a few percent of the desired molecule is mixed in an excess of light driver gas. This accelerates the heavier seed molecules, and also cools the translational, rotational, and vibrational degrees of freedom of the molecules. The translational acceleration and simultaneous cooling in the beam can be studied by molecular beam techniques coupled to mass spectroscopy, like rapid mechanical chopping and molecular time-of-flight measurements. The rotational and vibrational temperatures are much harder to determined in an ordinary molecular apparatus, and some optical spectroscopic method is usually needed [3,4,5].
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Sepiol, Jerzy, Frank Güttler, Marco Pirotta, Alois Renn, and Urs P. Wild. "High Resolution Spectroscopy on Single Molecules." In High Resolution Spectroscopy. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/hrs.1993.wa5.

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Single particle spectroscopy has become a source of valuable information on fundamental interactions between light and matter. Whereas trapping and cooling of ions and atoms has been sucessfully achieved, single molecules, because of their multilevel structure (high number of internal degrees of freedom) have not been observed in electromagnetic traps so far. However due to the presence of zero phonon lines in conjunction with inhomogeneous broadening the spectroscopic isolation and detection of single molecules ‘trapped in solids at very low temperatures' is made feasible [1,2]. Single molecule spectroscopy allows to study the distribution of molecular properties and not only the statistical average which is generally observed.
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Bardeen, C. J., and C. V. Shank. "Solvent Dependence of the Femtosecond Three Pulse Photon Echo for LD690 in n-Alcohols." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/up.1994.thd.16.

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The characteristic timescales of the solvent-solute interaction are of great interest to those studying the spectroscopy and reaction dynamics of molecules in condensed phases. These timescales influence a variety of linear and non-linear spectroscopic measurements, and together these different types of measurements should constrain the quantitative values of the interaction parameters. In this work we use both linear (absorption and fluorescence) and non-linear (resonance raman and femtosecond time-resolved 4-wave-mixing) spectroscopies to systematically investigate the spectral broadening of the dye molecule LD690 in a series of n-alcohols.
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Syage, Jack A., and John E. Wessel. "Ion Dip Spectroscopy and Multiresonant Processes in Aromatic Molecules by Supersonic Molecular Beam Mass Spectroscopy." In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1987. http://dx.doi.org/10.1364/laca.1987.pdp12.

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Harris, T. D., J. J. Macklin, J. K. Trautman, and L. E. Brus. "Imaging and Time-Resolved Spectroscopy of Single Molecules." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/lacea.1996.lwd.5.

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Recent progress in the fluorescence detection of individual molecules [1-8] suggests that a single dye molecule can be a useful tool to probe chemical identity and activity. Measurement of fluorescence lifetime [5,6] and spectrum [6] can be augmented by knowledge of molecular orientation using polarized light [3], and triplet [2] and photoisomer excitation, as well as diffusion processes, via fluorescence-intensity correlation. Applications of fluorescent probes include the study of the dynamic conformation of membrane-bound proteins, transport of and signaling by messenger molecules, and the optical detection of the sequence of DNA. While molecules can be spatially located using near-field microscopy [5-8], near-field probes can perturb the molecule under study. We show here that molecular properties can be determined easily and in a non-perturbative manner using far-field illumination, and we obtain unperturbed spectral and lifetime data that cannot be extracted from an ensemble measurement.
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Pirotta, Marco, Frank Güttler, Jerzy Sepiol, Alois Renn, and Urs P. Wild. "Single Molecule Spectroscopy: Fluorescence Lifetime of Pentacene in p-Terphenyl." In Spectral Hole-Burning and Luminescence Line Narrowing: Science and Applications. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/shbl.1992.pd6.

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Single molecule spectroscopy opens a wide field of research. Fundamental spectroscopic properties such as inhomogeneous broadening, spectral diffusion, and homogeneous dephasing can be investigated. Moerner and Kador first succeeded in detecting single pentacene molecules in a p-terphenyl host crystal by using a double modulated absorption technique [1]. Orrit and Bernard used a fluorescence excitation [2] technique to detect single molecules. Spectroscopic measurements of the quadratic Stark effect were performed by Wild, Güttler, Pirotta, and Renn [3].
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Friedman-Hill, Ernest J., and R. W. Field. "Fluorescence-based intracavity laser spectroscopy of free radicals." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/oam.1990.wn3.

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Two special problems confront the spectroscopist who studies transition-metal containing diatomic molecules: the dominance of nominally forbidden s-d and d-d metal-centered transitions, which make the application of non-linear spectroscopies difficult; and the huge number of molecular states, which dilute the observable laser-induced fluorescence at a given detection wavelength. To combat both of these problems simultaneously, we have constructed a fluorescencebased continuous wave, laser intracavity spectrometer which provides tunable laser light of high intensity (> 500 W/cm2) over a large spatial region (greater than 0.1 cm3), greatly increasing the amount of observable fluorescence and facilitating saturation of weak optical transitions as compared to extracavity spectroscopy. Using examples from the spectra of gas phase 58NiH, 61NiH, and 58NiO radicals, we illustrate the capability of this spectrometer to rapidly and efficiently gather information crucial to the verification of electronic structure models.
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Arrington, Caleb A., Jon D. Langenberg, Jacqueline C. Pinegar, Michael D. Morse, Mats Doverstål, Bo Lindgren, and Ulf Sassenberg. "High Resolution Spectroscopy of Ti2 and AlY at Near-Infrared Frequencies." In High Resolution Spectroscopy. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/hrs.1993.pd4.

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High resolution jet-cooled molecular beam spectroscopy has been effective in revealing the bonding between transition metals. One periodic trend that has developed during the study of small transition metal molecules is the relatively weak bond strength in the early 3d transition metals (Sc2, Ti2 in comparison to middle (V2, Cr2) or late (Ni2, Cu2) members of the 3d series. This trend of bond strengths in early transition metals is not so pronounced in the 4d and 5d metals where d-bonding is a major contributor to molecular stability. Low bond strengths in molecules, whether due to poor d overlap or high s ← d promotion energy, provides a challenge to the spectroscopist. It has been shown that diatomic systems with a large density of electronic states, as is usually the case for open d-subshell molecules, undergo a rapid predissociation (τ < 5 ns) when excited above the lowest dissociation limit.1 The extreme density of states responsible for predissociation also precludes isolation of single rovibronic states suitable for high resolution spectroscopy at energies near the dissociation limit of these molecules. The spectroscopist interested in investigating species with low bond strengths and high densities of electronic states, as in our investigation of Ti2 and AlY, is forced to search the low energy near-infrared region for isolated electronic states that are not hopelessly perturbed. In the present near-infrared investigation of Ti2 and AlY we have employed resonant two photon ionization (R2PI) as the detection strategy for obtaining optical spectra in a jet-cooled molecular beam.
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Asher, Sanford A. "Biological Applications of UV Raman Spectroscopy: Static and Dynamical Studies." In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/laca.1990.ma6.

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The recent development of UV Raman spectroscopy has led to careful studies of the enhancement mechanism of vibrational modes for both small molecules such as amides, small aromatic molecules such as substituted benzene derivatives and also larger molecules such as polycyclic aromatic hydrocarbons, DNA and proteins The objective of the small molecule studies is to characterize the resonance Raman enhancement mechanisms to examine molecular excited state structure. These studies also clarify the resonance Raman enhancement mechanisms which clarify the dependence of Raman enhancement upon molecular environment. We will present an overview of this work as it relates to ongoing UV resonance Raman studies of the heme protein structure and function and the investigation of the details of the hemoglobin cooperativity mechanism.
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Reports on the topic "Molecular spectroscopie"

1

Seeman, Jeffrey I., Henry V. Secor, P. J. Breen, V. H. Grassian, and E. R. Bernstein. A Study of Non-Rigid Aromatic Molecules by Supersonic Molecular Jet Spectroscopy: Observation and Spectroscopic Analysis of the Stable Conformations of Various Alkylbenzenes. Fort Belvoir, VA: Defense Technical Information Center, July 1988. http://dx.doi.org/10.21236/ada199409.

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Ho, Wilson. Spectroscopic Imaging of Molecular Functions at Surfaces. Office of Scientific and Technical Information (OSTI), December 2018. http://dx.doi.org/10.2172/1485203.

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Superfine, R. Nonlinear spectroscopic studies of interfacial molecular ordering. Office of Scientific and Technical Information (OSTI), July 1991. http://dx.doi.org/10.2172/5004428.

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Miller, J. (Multiphoton spectroscopy of molecules). Office of Scientific and Technical Information (OSTI), June 1988. http://dx.doi.org/10.2172/6850176.

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Weber, A. Technical activities 1986-1988 Molecular Spectroscopy Division. Gaithersburg, MD: National Institute of Standards and Technology, 1989. http://dx.doi.org/10.6028/nist.ir.89-4051.

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Miller, J. (Spectroscopy of atoms, molecules, and clusters). Office of Scientific and Technical Information (OSTI), December 1989. http://dx.doi.org/10.2172/5178445.

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Michael Holman, Ling Zang, Ruchuan Liu, and David M. Adams. Single Molecule Spectroscopy of Electron Transfer. Office of Scientific and Technical Information (OSTI), October 2009. http://dx.doi.org/10.2172/966129.

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8

Johnson, P. Studies of atmospheric molecules by multiphoton spectroscopy. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/5075777.

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9

Roy, Dibyendu, Yan Li, Alex Greilich, Yu Pershin, Avadh B. Saxena, and Nikolai Sinitsyn. Spin noise spectroscopy of quantum dot molecules. Office of Scientific and Technical Information (OSTI), May 2013. http://dx.doi.org/10.2172/1079572.

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10

Johnson, P. M. Studies of atmospheric molecules by multiphoton spectroscopy. Office of Scientific and Technical Information (OSTI), October 1991. http://dx.doi.org/10.2172/5394803.

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