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Published: 4 June 2021

Last updated: 31 January 2023

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1

Fullagar, Wilfred Kelsham, and w_fullagar@hotmail com. "Molecular Fullerides." The Australian National University. Research School of Chemistry, 1997. http://thesis.anu.edu.au./public/adt-ANU20010831.150750.

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The closed shell structures of certain all-carbon fragments originally observed in mass spectroscopy experiments leads to the enhanced stability of these species, known as fullerenes, which have excited sufficient interest amongst chemists and physicists over the last decade to warrant the award of the 1996 Nobel Prize for Chemistry to their discoverers. ¶ Studies of the stability, symmetry, and consequent remarkable properties of fullerenes began in earnest in 1991 with the development of a technique enabling the production and purification of macroscopic quantities of material. The best known and most widely studied fullerene is the truncated icosahedral C[subscript 60] molecule, which forms the basis of the present work. ¶ One important property of C[subscript 60] is that it forms salts with sufficiently electropositive species, such as the alkali metals. The resulting salts contain C[subscript 60] anions and are known as fullerides. Certain of these salts display metallic behaviour, and some superconduct at temperatures as high as 33 K. ¶ Three aspects of fulleride research are addressed in this work. These are: i) the preparation, crystal structure determination and superconductivity characterization of several new fullerides, particularly those including ammonia as an additional intercalant; ii) the electronic structure of the C[superscript n-, subscript 60] (n = 1 - 6) anions, as probed by solution-phase near infrared absorption spectroscopy; and iii) the molecular dynamics of a number of fullerides, superconducting and non-superconducting, by inelastic neutron scattering. ¶ This work has grown out of an Honours project also concerning C[subscript 60], the combined duration of the two studies covering essentially the entire history of this widely and competitively studied field.

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2

Allen, Katharine M. "Intercalation chemistry of alkali metal fullerides." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390457.

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3

MacFarlane, W. Andrew. "[nu]SR studies of the metallic alkali fullerides." Thesis, University of British Columbia, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0031/NQ27192.pdf.

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4

Kim, Joon Hong. "Electrochemical measurements and thermodynamic properties of alkali fullerides." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/NQ42745.pdf.

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5

Kim, Joon Hong. "Electrochemical measurements and thermodynamic properties of alkali fullerides /." *McMaster only, 1997.

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6

Rahmer, Jürgen. "Electronic spin states in fullerides and endohedral fullerenes." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10934928.

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7

Denning, Mark Simon. "Intercalation chemistry of higher fullerenes." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343444.

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8

VICTOROFF, WLADIMIR. "Supraconductivite et transitions de phases dans les fullerides alcalins." Paris 11, 1997. http://www.theses.fr/1997PA112260.

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Dans cette these nous avons etudie les transitions de phase dans les fullerides alcalins, et en particulier la phase supraconductrice a#3c#6#0, ou a represente un alcalin. Apres une presentation generale des proprietes structurales et electroniques des composes de la famille a#nc#6#0, nous exposons plus specifiquement dans un deuxieme chapitre les proprietes de la phase supraconductrice a partir des donnees experimentales. Cette supraconductivite, de caractere classique, presente des temperatures critiques exceptionnellements elevees, inegalee en dehors des cuprates. Les mesures experimentales faisant apparaitre la presence de fortes correlations electroniques nous conduisent au troisieme chapitre a etudier leur influence sur cette phase. Notre etude confirme que ces correlations ne doivent pas etre trop importantes pour pouvoir interpreter les resultats experimentaux. Dans le chapitre suivant, nous etudions l'influence de la grande energie de debye comparee a l'energie de fermi dans le cadre du modele d'eliashberg. Nous montrons que pour des valeurs realistes du rapport #d/e#f dans le cas des fullerides alcalins l'effet est presque nul. Dans le cinquieme chapitre, nous etudions les deformations jahn-teller de la molecule de c#6#0 et nous montrons qu'elles peuvent etre la source de nouvelles correlations electroniques, dependant fortement du remplissage. Ceci permet d'interpreter le diagramme de phase surprenant des fullerides alcalins qui fait apparaitre une alternance de phases fortement et faiblement correlees. Enfin, au sixieme chapitre, nous abordons l'etude des phases magnetiques dans les composes a#1c#6#0 que nous interpretons a partir de calculs de structure de bande, combines a des correlations electroniques intermediaires predites pour ces composes dans le chapitre precedent.

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9

Touzik, Andrei. "Simulation der Nanostrukturbildung in Alkali-dotierten Fullerenschichten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1081344263703-58568.

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This work presents theoretical background for the investigation of nanostructure formation in alkali-metal doped fullerene layers. A number of computational methods are used to describe structural transformation in the fullerene layer. They include tight-binding molecular dynamics, empirical molecular dynamics, Monte-Carlo calculations as well as other methods. The doped fullerene layers show the highest superconducting critical temperature among organic superconductors. A new electrochemical method of synthesis of potassium and rubidium fullerides has been recently developed by Professor Dunsch and coworkers in the department of electrochemistry and conductive polymers at IFW Dresden. The process of electrochemical doping is accompanied by several side effects, and one of them is nanostructure formation at the surface of the fullerene layer. In the present work an explanation is given for the nanostructure formation observed recently by scanning tunnel microscopy. The corresponding model is based on the concept of spontaneous phase separation that has been realized by kinetic Monte Carlo calculations. These calculations predict instability of initially homogeneous alkali-doped fullerene layers. Due to the significant gap in the Madelung energy formation of an alkali-poor and an alkali-reach phase is expected. The results of the Monte Carlo simulations point out that the particle size of the corresponding phases remains in the nanometer range. Interpretation of experimental data for metal deposition on fullerene substrates can be easily given in the framework of the phase separation concept as well. Metal clusters of the size order 50 to 100 nm emerge in course of electrochemical copper deposition on alkali-doped fullerene layers. The electrically conductive paths through the insulating fullerene layer are probably responsible for the inhomogeneous copper deposition under electrochemical conditions. A novel computer program has been developed in course of this work, which is designed as a distributed application. It can be used for diverse conventional and kinetic Monte Carlo calculations
Die vorliegende Arbeit präsentiert theoretische Arbeiten, die das Ziel haben, die Nanostrukturbildung in dotierten Fullerenschichten zu verstehen. Diverse Rechenmethoden wurden verwendet, um die strukturellen Umwandlungen in der Fullerenschicht zu beschreiben. Die Tight-Binding-Molekulardynamik, die empirische Molekulardynamik und Monte-Carlo-Berechnungen sowie andere Methoden sind eingeschlossen. Die dotierten Fullerenschichten zeigen die höchste supraleitende kritische Temperatur unter den organischen Supraleitern. Eine neue elektrochemische Methode der Synthese von Kalium- und Rubidium-Fulleriden wurde vor kurzem von Professor Dunsch und Mitarbeitern in der Abteilung Elektrochemie und leitfähigen Polymere am IFW Dresden entwickelt. Der Prozess der elektrochemischen Dotierung wird von mehreren Nebenprozessen begleitet, und einer davon ist die Nanostrukturbildung an der Oberfäche der Fullerenschicht. In der vorliegenden Arbeit wird eine Erklärung für die Herausbildung der Nanostrukturen, die mit Hilfe von Rastertunnelmikroskopie beobachtet wurden, gegeben. Das entsprechende Modell basiert auf dem Konzept der spontanen Phasenentmischung und wird durch kinetische Monte-Carlo-Simulationen realisiert. Diese Simulationen sagen Instabilität der zunächst homogenen Alkali-dotierten Fullerenschichten voraus. Wegen des wesentlichen Unterschieds in der Madelungenergie ist die Herausbildung einer Alkalimetall-armen und einer Alkalimetall-reichen Phase zu erwarten. Die Ergebnisse der Monte-Carlo-Simulationen weisen darauf hin, dass die Teilchengröße der entsprechenden Phasen im Nanometer-Bereich bleibt. Im Rahmen des Phasenentmischungskonzepts können auch experimentelle Daten zur Metallabscheidung auf Fullerensubstraten problemlos interpretiert werden. Bei elektrochemischer Kupferabscheidung auf Alkali-dotierten Fullerenschichten entstehen Metallcluster der Größenordnung von 50 bis 100 nm. Die elektrisch leitfähige Pfade, die in einer isolierenden Matrix auftreten, sind wahrscheinlich für die ungleichmäßige Kupferabscheidung unter elektrochemischen Bedingungen verantwortlich. Ein neuartiges Computerprogramm wurde im Rahmen dieser Arbeit entwickelt, das als eine verteilte Anwendung entworfen ist. Damit können diverse konventionelle und kinetische Monte-Carlo-Simulationen durchgeführt werden

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10

Nakagawa, Takeshi. "Rare-earth based fullerides : tuning the onset of valency transitions." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/2112/.

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In this thesis, the recent advances in studies on rare-earth metal intercalated fullerene solids with emphasis on their structural, electronic, and magnetic properties. The investigations on the rare-earth based fullerides have been concentrated on their structural, electronic, and magnetic properties. Intercalation of C(_60) with rare-earth metals results in interesting compounds not only for the appearance of superconductivity but also for the magnetic properties and mixed valence phenomena related to the localised 4f electrons. Of particular interest, I discuss the results obtained from various experiments on rare-earth based mixed valence fullerides, of which displays a remarkable sensitivity of rare-earth valency to external stimuli, such as temperature and pressure. Among the family of rare-earth fullerides, Sm(_2.75)C(_60) was the first known molecular-based material to show valence fluctuation associated with the highly-correlated narrow-band behaviour of the 4f electrons in Sm ions. Improvement in the synthetic technique to produce single-phase rare-earth doped fullerides have opened the way to carry out detailed and systematic study of the structural properties of the RE(_2.75)C(_60) (RE = Sm, Eu, and Yb) as a function of temperature and pressure, which were carried out using the synchrotron X-ray powder diffraction technique. The obtained results have lead us to find a rich variety of temperature- and pressure-driven abrupt or continuous valence transitions. In addition, we have observed that by taking precise control on the nature of dopants, the tuning of the onset temperature and pressure of this valence transition were possible. Direct measurements on the valence states of the rare-earth ions in the fulleride salts as a function of temperature were carried out using X-ray absorption spectroscopy using the alkaline-earth and rare-earth mixed compound, (Sm(_2/3)Ca9_1/3))(_2.75) C(_60). The obtained spectra have provided clear evidence to confirm the electronic nature of the low-temperature first-order valence transition.

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11

Okur, Havva Esma. "Experimental investigations of correlated electron systems : alkali fullerides and sesquioxides." Thesis, Durham University, 2016. http://etheses.dur.ac.uk/11644/.

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The work reported in this thesis systematically investigates the structural, electronic and/or magnetic properties of fcc AxCs3-xC60 fullerides (A = K and Rb) and of sesquioxide Cs4O6 under ambient and non-ambient temperature and pressure conditions, employing X-ray and neutron powder diffraction, muon spin relaxation, and SQUID magnetometry. In the AxCs3-xC60 alkali fullerides, unconventional superconductivity can emerge through tuning of intermolecular distances. While conventional BCS-like response is found in the underexpanded regime of the electronic phase diagram, significant deviations appear in the overexpanded region adjacent to the Mott boundary where strong electron correlations are prominent. In this work, the solid-state synthesis of fcc KxCs3−xC60 (0.12 ≤ x ≤ 2) superconducting materials, with intermolecular distances controlled via adjusting the K+/Cs+ dopant ratio, is reported. Whilst the structural, electronic and magnetic properties of fcc KxCs3−xC60 are reminiscent of those previously reported for fcc RbxCs3−xC60, i.e. the Mott boundary can be shifted to ambient pressure and the metal-insulator crossover temperature can be tuned by such chemical pressurisation of Cs3C60, cation-specific effects are of importance on the electronic properties of fcc AxCs3−xC60. This work also provides strong evidence for correlated behaviour in the overexpanded regime through examining the presence or not of the Hebel-Slichter coherence peak and extracting the superconducting gap magnitude. Crystallographically, the alkali sesquioxides A4O6 (A = Rb, Cs), at high and low temperature, had been reported to adopt a cubic structure which generates a single crystallographic position for dioxygen, implying charge disorder: A4(O2(4/3)-)3. Conversely, spectroscopy studies at 5 K found evidence for two localized valence states of dioxygen, indicating charge ordering: (A+)4(O2−)2(O22−). This issue is addressed with the first systematic investigation of the temperature- and cooling-protocol-dependent structural evolution of Cs4O6, revealing the existence of a valence-ordered state at low temperature and also that valence disorder-order transitions can be induced by temperature, pressure and X-ray illumination.

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12

Touzik, Andrei. "Simulation der Nanostrukturbildung in Alkali-dotierten Fullerenschichten." Doctoral thesis, Technische Universität Dresden, 2003. https://tud.qucosa.de/id/qucosa%3A24324.

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This work presents theoretical background for the investigation of nanostructure formation in alkali-metal doped fullerene layers. A number of computational methods are used to describe structural transformation in the fullerene layer. They include tight-binding molecular dynamics, empirical molecular dynamics, Monte-Carlo calculations as well as other methods. The doped fullerene layers show the highest superconducting critical temperature among organic superconductors. A new electrochemical method of synthesis of potassium and rubidium fullerides has been recently developed by Professor Dunsch and coworkers in the department of electrochemistry and conductive polymers at IFW Dresden. The process of electrochemical doping is accompanied by several side effects, and one of them is nanostructure formation at the surface of the fullerene layer. In the present work an explanation is given for the nanostructure formation observed recently by scanning tunnel microscopy. The corresponding model is based on the concept of spontaneous phase separation that has been realized by kinetic Monte Carlo calculations. These calculations predict instability of initially homogeneous alkali-doped fullerene layers. Due to the significant gap in the Madelung energy formation of an alkali-poor and an alkali-reach phase is expected. The results of the Monte Carlo simulations point out that the particle size of the corresponding phases remains in the nanometer range. Interpretation of experimental data for metal deposition on fullerene substrates can be easily given in the framework of the phase separation concept as well. Metal clusters of the size order 50 to 100 nm emerge in course of electrochemical copper deposition on alkali-doped fullerene layers. The electrically conductive paths through the insulating fullerene layer are probably responsible for the inhomogeneous copper deposition under electrochemical conditions. A novel computer program has been developed in course of this work, which is designed as a distributed application. It can be used for diverse conventional and kinetic Monte Carlo calculations.
Die vorliegende Arbeit präsentiert theoretische Arbeiten, die das Ziel haben, die Nanostrukturbildung in dotierten Fullerenschichten zu verstehen. Diverse Rechenmethoden wurden verwendet, um die strukturellen Umwandlungen in der Fullerenschicht zu beschreiben. Die Tight-Binding-Molekulardynamik, die empirische Molekulardynamik und Monte-Carlo-Berechnungen sowie andere Methoden sind eingeschlossen. Die dotierten Fullerenschichten zeigen die höchste supraleitende kritische Temperatur unter den organischen Supraleitern. Eine neue elektrochemische Methode der Synthese von Kalium- und Rubidium-Fulleriden wurde vor kurzem von Professor Dunsch und Mitarbeitern in der Abteilung Elektrochemie und leitfähigen Polymere am IFW Dresden entwickelt. Der Prozess der elektrochemischen Dotierung wird von mehreren Nebenprozessen begleitet, und einer davon ist die Nanostrukturbildung an der Oberfäche der Fullerenschicht. In der vorliegenden Arbeit wird eine Erklärung für die Herausbildung der Nanostrukturen, die mit Hilfe von Rastertunnelmikroskopie beobachtet wurden, gegeben. Das entsprechende Modell basiert auf dem Konzept der spontanen Phasenentmischung und wird durch kinetische Monte-Carlo-Simulationen realisiert. Diese Simulationen sagen Instabilität der zunächst homogenen Alkali-dotierten Fullerenschichten voraus. Wegen des wesentlichen Unterschieds in der Madelungenergie ist die Herausbildung einer Alkalimetall-armen und einer Alkalimetall-reichen Phase zu erwarten. Die Ergebnisse der Monte-Carlo-Simulationen weisen darauf hin, dass die Teilchengröße der entsprechenden Phasen im Nanometer-Bereich bleibt. Im Rahmen des Phasenentmischungskonzepts können auch experimentelle Daten zur Metallabscheidung auf Fullerensubstraten problemlos interpretiert werden. Bei elektrochemischer Kupferabscheidung auf Alkali-dotierten Fullerenschichten entstehen Metallcluster der Größenordnung von 50 bis 100 nm. Die elektrisch leitfähige Pfade, die in einer isolierenden Matrix auftreten, sind wahrscheinlich für die ungleichmäßige Kupferabscheidung unter elektrochemischen Bedingungen verantwortlich. Ein neuartiges Computerprogramm wurde im Rahmen dieser Arbeit entwickelt, das als eine verteilte Anwendung entworfen ist. Damit können diverse konventionelle und kinetische Monte-Carlo-Simulationen durchgeführt werden.

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13

Grasso, Giuseppe. "Solid-state NMR studies of alkali fullerides and long-chain alkanes." Thesis, University of Nottingham, 2004. http://eprints.nottingham.ac.uk/10051/.

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The main focus of this thesis is the investigation of structure and motion of different materials by applying different solid-state NMR techniques. In the first section (1) some of the bases of NMR are described both in a Classical (1.1) and Quantum Mechanical (1.2) approach, while the next two sections deal with the experimental part of the work. In section 2 solid-state NMR studies of CsC60 are described and an unambiguous assignment of the 13C NMR spectrum of the polymer phase of CsC60, which is based solely on our experimental data, is presented. In contrast to previous work, the assignment does not rely on the knowledge of the electronic structure of this material and our results support a fully three-dimensional electronic structure as opposed to a quasi one-dimensional one. This is achieved using a two-dimensional 13C MAS NMR correlation experiment, which identifies nuclei coupled via a through-bond scalar interaction, the Refocused INADEQUATE. In section 3 solid-state NMR experiments performed on polyethylene and long-chain n-alkanes corresponding to the formula C246H494 are described. Particular attention is given to some specific issues such as chain folding and a detailed study of the saturation-recovery curves (T1) obtained is carried out for different materials. The model elaborated is able to simulate all the data recorded and the presence of an interphase between the crystalline and the amorphous parts of the samples is proposed. To help the understanding of the structure and the motion of long-chain n-alkanes in section 3 some deuterated samples such as C216H434-d24 and C12H25(CH2)192CHDC11D23+C162H326 ("the mixture") are also studied. Deuterium NMR is widely used and we fit all the experimental line shape of the different samples at different temperatures. Diverse models for the structure and motion of such materials are given, which take into account all the experimental results obtained.

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14

Macovez, Roberto. "Surface electronic structure of fullerides effects of correlation, electron-phonon coupling, and polymerization /." [S.l. : Groningen : s.n. ; University Library of Groningen] [Host], 2007. http://irs.ub.rug.nl/ppn/305433423.

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15

Lee, Daniel. "Development of high-resolution two-dimensional correlation spectroscopy in solid-state NMR : applications to nanocomposites and fullerides." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/11864/.

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Two-dimensional correlation spectroscopy in solid-state NMR is an immensely important tool for the analysis of materials, such as technologically interesting nano-materials or bio-materials. After detailing one method that returns high-resolution one-dimensional solid-state proton NMR spectra, high-resolution proton-proton two-dimensional correlation experiments are described and demonstrated. Subsequently, a new two-dimensional NMR experiment is described which is suitable for obtaining a high-resolution proton dimension in heteronuclear dipolar correlation spectra of solids. This new experiment has been used to characterise the interface between the organic and inorganic components of "coreshell" colloidal nanocomposite particles. In addition, a new two-dimensional NMR experiment is described which is suitable for obtaining homonuclear scalar correlation spectra in solids. This new experiment has several advantages, including increased cross peak intensities coupled with good suppression of the diagonal. Its utility is demonstrated via carbon-13 spectra of natural abundance samples as well as the polymer phase of caesium fulleride.

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16

Howard, Christopher Anthony. "Metal-ammonia-fulleride solutions." Thesis, University College London (University of London), 2005. http://discovery.ucl.ac.uk/1445641/.

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This project is the first concerted effort to study the structure of metal-ammonia- fulleride solutions. These novel solutions contain high concentrations of fulleride anions, C6on" (n = 1 to 5). A detailed understanding of the solubility of fullerenes and their derivatives has long been sought after: something this project addresses. The work focuses on the structure of the solutions using the complementary techniques of wide angle neutron diffraction, Small Angle Neutron Scattering (SANS), and Monte Carlo simulations. A highly developed structure is found over the short and intermediate length scales. The results show concentrated solutions of solvent separated, strongly coordinated, fulleride anions, maintained by an intriguing reorganisation of the ammonia solvent around the anions in solution. In more detail, we find two solvation shells around the C6o anions containing around 45 and -80 ammonia molecules respectively. The ammonia solvent molecules direct one of their hydrogen atoms towards the centre of the Ceo anions, allowing the other two hydrogen atoms to complete hydrogen-bonds within and across the shells. The solvation structure of the cation in solution is found to be very similar to its solvation structure in bulk metal-ammonia solutions. The structure and stability of the solutions is found to be dependent on both anionic charge and cation charge density. The scientific importance of the solutions is demonstrated by the attainment of high quality 13C NMR spectra for the fulleride anions Ceo"" {n = 1 to 5) for the first time in an identical solvent. Previous limitations of low concentrations, poor quality samples, and restrictions due to the air sensitivity of the anions have been overcome. The data here includes the first l3C NMR spectrum of C6o5". These data reveals that all the carbon atoms have an identical electronic environment in this anion.

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17

Margadonna, Sarena. "Fulleride salts : from polymers to superconductors." Thesis, University of Sussex, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323048.

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18

Borton, Peter Thomas. "Preparation and Characterization of Manganese Fulleride." University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1354556594.

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19

Stenger, Victor A. "NMR Studies of Alkali Fulleride Superconductors /." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487932351060018.

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20

Margiolaki, Irene. "Structural, magnetic and dynamic properties of fullerene based materials." Thesis, University of Sussex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288785.

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21

McDonald, Martin Thomas. "Structural and electronic properties of fulleride superconductors." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/301/.

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In the present thesis, I discuss some of the current advances in research in the field of the solid state science of fullerenes. The reaction of C60 with alkali metals using both conventional solid state and low temperature solution-based synthesis techniques has led to the production of fulleride salts with interesting structural and superconducting properties. In superconducting A3C60 systems, it has been widely reported that Tc increases monotonically with interfulleride separation. Of particular interest is the family Na2Rb1-xCsxC60 (0 ≤ x ≤ 1) as they display a much steeper rate of change of Tc with interfulleride spacing. Here we discuss the related family of quaternary fullerides, Na2-xKxCsC60 in an attempt to explore the consequences of this trend and produce fulleride salts with elevated Tc's In addition, the monotonic increase in Tc with increasing interfulleride separation has driven attempts towards the synthesis of new superconducting fullerides with very large lattice parameters. A key material among the A3C60 systems is the end member, Cs3C60, which has remained elusive in attempts to synthesise it by traditional solid state techniques due to the thermodynamic instability of this phase caused by the accommodation of the large Cs+ ion (r = 1.67 Å) in the small tetrahedral holes (r = 1.12 Å). Here we report the synthesis of “FCC rich” and "A15 rich" samples of the series, RbxCs3-xC60 (0.0 ≤ x ≤ 0.5) via low temperature synthetic techniques utilising the solvents ammonia and methylamine, respectively. This allowed us to study the effects of both chemical (by partial substitution of Cs+ by the smaller Rb+ cation) and physical pressure upon the electronic and superconducting properties of these materials. For all samples, detailed structural studies have been performed using synchrotron X-ray powder diffraction and magnetic behaviour using SQUID magnetometry techniques.

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22

Armbruster, Johannes [Verfasser]. "Elektronen-Energieverlustspektroskopie an Fullerenen und Fulleriden / Johannes Armbruster." Karlsruhe : KIT-Bibliothek, 1996. http://d-nb.info/1115251538/34.

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23

Brumm, Holger. "Synthese, Kristallstruktur und Bindungseigenschaften von Fulleriden und Fullerensolvaten." [S.l. : s.n.], 2002. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10447206.

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24

Vavekis, Konstantinos. "Structural, magnetic and superconducting properties of fulleride salts." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362276.

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25

Zadik, Ruth Helen. "Structural, electronic and magnetic properties of fulleride materials." Thesis, Durham University, 2015. http://etheses.dur.ac.uk/11187/.

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This thesis outlines new research findings into the solid-state properties of selected alkali- and alkaline-earth-intercalated fullerides, focusing on their structural, electronic and magnetic properties at ambient and non-ambient temperatures and pressures, primarily employing synchrotron X-ray powder diffraction and SQUID magnetometry. Understanding the relationship between superconducting, neighbouring insulating and normal metallic states above Tc in unconventional superconductors is fundamentally important. Highly expanded fcc Cs3C60 behaves very differently to underexpanded A3C60 alkali fullerides such as K3C60 and Rb3C60. Whilst superconductivity in the latter seems well described by conventional Bardeen-Cooper-Schrieffer (BCS) theory, Cs3C60, a Mott-Jahn-Teller insulator under ambient pressure, exhibits distinctly non-BCS type superconductivity upon pressurisation. The intermediate regime adjacent to the Mott boundary, where strong electronic correlations are prominent, was hitherto only studied through physical pressurisation of Cs3C60 to tune the intermolecular spacing. This thesis reports the solid-state synthesis of fcc-rich RbxCs3−xC60 (0.25 ≤ x ≤ 2) bulk superconducting materials, with excellent stoichiometry control, and the effects on the electronic properties in situ of tuning intermolecular separation by varying temperature, physical and chemical pressurisation via adjusting the cation dopant ratio. It is shown that the Mott boundary can be traversed at ambient pressure upon cooling, and the metal-insulator crossover temperature tuned by chemical and physical pressurisation. A15 Cs3C60 orders antiferromagnetically below 46 K. Previous studies found no evidence of symmetry lowering or discontinuous structural changes upon magnetic ordering, despite theoretical predictions to the contrary. This issue is addressed with the first systematic ultrahigh-resolution investigation of its structural evolution with temperature, evidencing a transition to a rhombohedral phase below TN. The structural properties of A15 Cs3C60 and Ba3C60 in situ upon pressurisation are described, extending previous work on A15 Cs3C60. This first study of the effects of compression on the latter system reveals a pressure-induced structural transition to a hitherto unreported monoclinic phase.

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26

Brands, Helge. "Ultrakurzzeitdynamik von Fulleriden in Lösung und suspendierten, längenselektierten Kohlenstoffnanoröhren." Karlsruhe Univ.-Verl. Karlsruhe, 2007. http://d-nb.info/989058131/04.

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Brands, Helge. "Ultrakurzzeitdynamik von Fulleriden in Lösung und suspendierten, längenselektierten Kohlenstoffnanoröhren." Karlsruhe : Universitätsverlag, 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007414.

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28

Chong, Lok C. "Palladium modified fullerite systems for catalytic applications." Thesis, University of Surrey, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604326.

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There has been a renewed interest in the crystallised form of Buckminsterfullerene due to advances in crystallisation techniques. In this thesis we demonstrate single-crystal, defect• free, liquid-liquid interfacial-precipitation of rods with hexagonal symmetry and faceted tips. The rods have a length:diametcr ratio of approximately 10:1, with diameters typically of the order of -500 mn. The fullerite properties were characterised using scanning electron microscopy, transmission electron spectroscopy, fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, ultra-violet/visible/near-infrared absorption spectroscopy and photoluminescence (PL) spectroscopy. This thesis contains a detailed study aimed at controlling the growth of fullerites through the careful manipulation of the experimental process parameters. As advances in understanding of the growth mechanism has been reported the controlled growth of fullerite rods with true nanoscale dimensions was achieved. The growth of fullerite rods with -50 run diameter as demonstrated represents an order of magnitude decrease in the scale of •structures obtained using the proposed methodology of fullerite synthesis. Furthermore, we have obtained through control of growth parameters other crystalline structures by controlling process parameters to give structures with large area:thickness ratios. Palladium is a metal of significant technological interest due to its wcJ1 known catalytic effect and affinity to hydrogen. In this thesis palladium is attached to the fullerites via exposure during a fast liquid-liquid interfacial-precipitation (FLLIP) process. A variety of attachment schemes were attempted including that of covalent and Van der Waals bonding and co-crystallization between the Pd and fullerite rods. Each palladium-fullerite is investigated for its potential as a heterogeneous catalyst for hydrogenation of 1-cthynyl – l-cyclohexanol, of which 100 % product selectivity was found for covalently bonded Pd~ful1erites. Furthermore, the covalently bonded Pd-fullerites have been placed in a CVD chamber and used to catalyse the growth of carbon nanotubes.

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Brands, Helge [Verfasser]. "Ultrakurzzeitdynamik von Fulleriden in Lösung und suspendierten, längenselektierten Kohlenstoffnanoröhren / von Helge Brands." Karlsruhe : Univ.-Verl. Karlsruhe, 2008. http://d-nb.info/989221687/34.

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30

Qian, Limin. "Soft X-Ray Spectroscopic Study of Fullerene Based Transition-Metal Compounds and Related Systems." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-5104-7/.

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31

Шумакова, Наталія Іванівна, Наталия Ивановна Шумакова, Nataliia Ivanivna Shumakova, and В. О. Скубко. "Формування острівців фулериту С[60] на вуглецевій підкладці." Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/45850.

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Метою роботи було розробка методики отримання плівок на основі фулерену С[60] з метою подальшого дослідження їх електрофізичних властивостей. Плівкові зразки були отриманні з використанням технології вакуумного термічного осадження або методом ультразвукового напилення за допомогою диспергатора УЗДН-А. Конденсацію здійснювали на підкладку із аморфної плівки вуглецю.

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32

Kromer, Alexander [Verfasser], and Emil [Akademischer Betreuer] Roduner. "C.W.-X-Band- und Puls-Q-Band-ESR-Untersuchungen an Übergangsmetallzentren in Zeolithen und an paramagnetischen Alkalimetall-Fulleriden / Alexander Kromer. Betreuer: Emil Roduner." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2013. http://d-nb.info/1034822969/34.

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33

BURTEAUX, BEATRICE. "Nouveaux composes du fullerite avec les accepteurs et les donneurs d'electrons : - fullerenes - fluorures de metaux de transition, - fullerenes - metaux alcalins lourds - benzene." Clermont-Ferrand 2, 1997. http://www.theses.fr/1997CLF21970.

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La premiere partie de ce travail est consacree a la synthese et la caracterisation des composes du fullerite avec les fluorures de metaux de transition : bf#3, tif#4, nbf#5, taf#5, mof#5, mof#6, irf#6, wf#6. Des composes contenant des taux variables de fluorures ont ete obtenus, a l'exception de bf#3 et mof#5, qui n'ont pas reagi. L'etude par diffraction des rayons x a revele l'existence de composes definis tres proches avec c#6#0-taf#5 et c#6#0-nbf#5. De nouvelles phases sont egalement apparues dans les composes c#6#0-mof#6 et c#6#0-irf#6. L'etude spectroscopique des composes formes (ir, rmn, rpe) indique que les especes presentes sont sous la forme de fluorures anioniques mf#x#-#n#+#x et de fluorures reduits. La presence de ces derniers peut alors etre expliquee par l'oxydation des fullerenes par le fluorure de depart. La deuxieme partie concerne l'etude de l'influence de l'insertion du benzene sur la structure et la supraconductivite des composes binaires a#xc#6#0, avec a = k, rb et x = 3, 4, 6. Une etude structurale preliminaire a revele une evolution de la structure des phases binaires sous l'effet de l'insertion du benzene, la plupart des composes presentant des symetries non cubiques. Les mesures de susceptibilite magnetique ont montre l'apparition d'un comportement supraconducteur dans les composes k#6c#6#0-c#6h#6, rb#6c#6#0-c#6h#6, et rb#4c#6#0-c#6h#6, alors que les phases binaires correspondantes sont isolantes. L'insertion du benzene n'a par contre entraine aucune modification de la supraconductivite des phases k#3c#6#0 et rb#3c#6#0. Cette etude confirme que le comportement supraconducteur des fullerides depend plus des proprietes electroniques intrinseques des fullerenes que de la structure des composes.

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34

Graßl, Tobias [Verfasser], and Nikolaus [Akademischer Betreuer] Korber. "Synthese und Charakterisierung von C₆₀-Fulleriden, Untersuchung der Reaktion von Kohlenhydraten in flüssigem Ammoniak und Umsetzung von Heptapnictiden (E = P, As) mit Ethinen und Gruppe-12-Metallkomplexen / Tobias Graßl ; Betreuer: Nikolaus Korber." Regensburg : Universitätsbibliothek Regensburg, 2017. http://d-nb.info/1141379627/34.

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35

Graßl, Tobias [Verfasser], and Nikolaus [Akademischer Betreuer] Korber. "Synthese und Charakterisierung von C₆₀-Fulleriden, Untersuchung der Reaktion von Kohlenhydraten in flüssigem Ammoniak und Umsetzung von Heptapnictiden (E = P, As) mit Ethinen und Gruppe-12-Metallkomplexen / Tobias Graßl ; Betreuer: Nikolaus Korber." Regensburg : Universitätsbibliothek Regensburg, 2016. http://d-nb.info/1135778213/34.

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36

Fullagar, Wilfred K. "Molecular Fullerides." Phd thesis, 1997. http://hdl.handle.net/1885/47059.

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The closed shell structures of certain all-carbon fragments originally observed in mass spectroscopy experiments leads to the enhanced stability of these species, known as fullerenes, which have excited sufficient interest amongst chemists and physicists over the last decade to warrant the award of the 1996 Nobel Prize for Chemistry to their discoverers. ¶ Studies of the stability, symmetry, and consequent remarkable properties of fullerenes began in earnest in 1991 with the development of a technique enabling the production and purification of macroscopic quantities of material. The best known and most widely studied fullerene is the truncated icosahedral C60 molecule, which forms the basis of the present work.

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37

MacFarlane, W. Andrew. "[mu]SR studies of the metallic alkali fullerides." Thesis, 1997. http://hdl.handle.net/2429/8562.

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Results of muon spin rotation (μ-SR) in the metallic intercalated C₆₀ compounds (AnC₆₀, where An are n alkali metal atoms) are presented. Except for the case of K₁C₆₀, the metallic state of these systems is unstable at low temperature (to a superconducting transition in A₃C₆₀ and a magnetic metal insulator transition in A₁C₆₀)- In A₃C₆₀, the properties of the metallic and superconducting states are investigated using i) diamagnetic muons to probe the distribution of internal magnetic field and ii) paramagnetic muonium (Mu) trapped within the C₆₀ cage to probe the electronic excitations. Mu is found to exhibit strong T₁ relaxation due to its interaction with the conduction electrons. In the superconducting state this relaxation rate exhibits a small enhancement (Hebel-Slichter coherence peak) which possesses an anomalously strong magnetic field supression. Exponential temperature dependence of the relaxation rate at low reduced temperature is observed, and from this estimates of the superconducting energy gap are obtained. At very low reduced temperature, deviations from this behaviour are found. Estimates of the magnetic penetration depth from broadening of the diamagnetic precession signal in the vortex state are also presented and discussed. In A₁C₆₀ (A = Rb and Cs), the magnetic state is investigated with zero field μ-SR. Observation of a small rapidly damped oscillation below 2K in Cs₁C₆₀ is the first evidence from μ-SR of magnetic order in these materials. The relaxation at higher temperature indicates that the internal fields are static and possess a broad distribution, indicating a highly disordered static magnetic structure. From the magnitude of the zero field relaxation rates, estimates of the magnitude of the internal field are made.

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38

Rahmer, Jürgen [Verfasser]. "Electronic spin states in fullerides and endohedral fullerenes / vorgelegt von Jürgen Rahmer." 2004. http://d-nb.info/969921306/34.

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39

Kozhemyakina, Nina V. [Verfasser]. "Synthesis of new fullerides via the "break-and-seal" approach and their characterization / vorgelegt von Nina V. Kozhemyakina." 2009. http://d-nb.info/999421476/34.

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40

Duty, Timothy Lee. "Muonium in C₆₀ fullerites : studies of structural and electronic properties." Thesis, 1993. http://hdl.handle.net/2429/1352.

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μSR studies of crystalline C₆₀ reveal the existence of two distinct paramagnetic states. The experiments described in this thesis confirm that one is an exohedrally bonded muonium radical, while the other is endohedral muonium with a hyperfine parameter Aμ, close to that of muonium in vacuum. The signal from the muonium-C₆₀ radical -- which is characterized by a small Aμ, (10% of Avacμ) and an anisotropic hyperfine interaction -- is sensitive to the molecular dynamics and is used to study the structural phase transition of solid C₆₀ near 260K. Only endohedral muonium is observed in the alkali-metal-doped fullerites K₄C₆₀, K₆C₆₀, and Rb₆C₆₀. From its coherent spin precession, we find all three to be semiconductors with small gaps on the order of 0.5 eV. Our results conflict with the simple band structure model of doped fullerites indicating that electron-electron correlation effects may be important in determining the electronic structure of these solids.

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41

Brumm, Holger [Verfasser]. "Synthese, Kristallstruktur und Bindungseigenschaften von Fulleriden und Fullerensolvaten / vorgelegt von Holger Brumm." 2003. http://d-nb.info/967268397/34.

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