Dissertations / Theses: 'Transition metals and their compounds'

1

Sze-To, Lap, and 司徒立. "The structural chemistry of coordination compounds containing d-block or f-block metals." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45204470.

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2

McGilligan, Brian Stephen. "Organometallic and related compounds of transition metals." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/46441.

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3

Berry, Adam. "Anionic polyhydride compounds of the transition metals." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670367.

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4

Carson, Cantwell G. "Noble and transition metal aromatic frameworks synthesis, properties, and stability /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29657.

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Thesis (Ph. D.)--Materials Science and Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Rina Tannenbaum; Committee Co-Chair: Rosario A. Gerhardt; Committee Member: E. Kent Barefield; Committee Member: Karl I. Jacob; Committee Member: Preet Singh; Committee Member: R. Bruce King. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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5

Collinson, J. S. "The reactions of lithium compounds with transition metals and hydrogen." Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355432.

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6

Ng, Yuk-wai, and 吳育煒. "Electronic transitions of transition metal monoborides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/195989.

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7

Dube, Paul A. "Properties of magnetic transition metal-bromide graphite intercalation compounds /." *McMaster only, 2002.

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8

Haddad, Timothy Samir. "Phosphine complexes of zirconium, hafnium and the lanthanoid metals." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31012.

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The synthesis of a variety of new lanthanoid phosphine complexes has been achieved by complexing either one or two amido-diphosphine ligands to yttrium, lutetium or lanthanum. At room temperature, the seven-coordinate bis(amido- diphosphine) complexes, MCl[N(SiMe₂CH₂PR₂)₂]₂- are fluxional and display NMR spectra indicative of complexes where the phosphorus donors are rapidly exchanging, probably via a dissociation-reassociation pathway. It is possible to generate thermally unstable hydrocarbyl complexes of the type, M(R)[N(SiMe₂CH₂PMe₂)₂]₂, which undergo a clean first order elimination of R-H to generate cyclometallated complexes of the type, M[N(SiMe₂CHPMe₂)(SiMe₂CH₂PMe₂)][N(SiMe₂CH₂PMe₂)₂]; the yttrium derivative was crystallographically characterized. These thermally robust compounds will undergo a-bond metathesis with H₂ and D₂ at high temperature, but appear to be too sterically congested to react with larger molecules. The synthesis of a series of mono(amido-diphosphine) lanthanoid complexes, MCl₂ [N(SiMe₂CH₂PR₂)₂], (R = Me, Ph, Pr', Bu[symbol omitted]) has also been achieved. Complexes of the type, MCl₂[N(SiMe₂CH₂PMe₂)₂], are insoluble in hydrocarbon solvents, presumably because they are oligomeric in nature. They will however, dissolve in THF probably forming seven-coordinate bis(THF) monomers. Attempts to alkylate these compounds generally led to decomposition; the cyclometallated bis(ligand) complex, M[N(SiMe₂CHPMe₂)(SiMe₂CH₂PMe₂)] [N(SiMe2CH2PMe2)2], was identified as the major product. A route to a dimeric mono(amido-diphosphine) allyl complex, {YCl(allyl)[N(SiMe₂CH₂PMe₂)₂]}₂ (characterized by crystallography) was found via the reaction of allyl-MgCl or Mg(allyl)₂(dioxane) with YCl[N(SiMe₂CH₂PMe₂)₂]₂. The mono(ligand) complexes containing bulky phosphine donors (R = Ph, Bu[symbol omitted], Pr[symbol omitted]) are soluble in hydrocarbon solvents; YCl₂[N(SiMe₂CH₂PPr[symbol omitted]₂)₂] can be isolated as either a THF adduct or as the base-free dimer. A new reaction, mediated by a zirconium or hafnium amido-diphosphine complex, where allyl and butadiene moieties are coupled together to generate a coordinated [ɳ⁴:ɳ¹-CH₂=CHCH=CHCH₂CH₂CH₂]¹- fragment has been investigated. The process is very sensitive to the nature of the ancillary ligands at the metal. For MCl(ɳ⁴-C₄H₆)[N(SiMe₂CH₂PR₂)₂] complexes, after the addition of allylMgCl, the transformation takes about one hour when M = Hf & R = Pr[symbol omitted], two hours when M = Zr & R = Pr[symbol omitted], a week when M = Hf & R = Me, and results only in decomposition when M = Zr & R = Me. Similarly, for the zirconium mediated coupling of 1-methylallyl with butadiene, when R = Me, decomposition occurs and when R = Pr[symbol omitted], after two hours the coupling is complete. Two of the four possible coupled products are formed in unequal amounts, and the coupling occurs exclusively at the substituted end of the 1-methylallyl unit as determined by X-ray crystallography. Which diastereomer is formed in excess was not determined. The reduction of ZrCl₃[N(SiMe₂CH₂PR₂)₂] (R = Pr[symbol omitted] or Bu[symbol omitted]) with Na/Hg amalgam under nitrogen results in the formation of a binuclear zirconium dinitrogen complex, {ZrCl[N(SiMe₂CH₂PR₂)₂]}₂ (μ-ɳ²:ɳ²-N₂). X-ray crystallography (for R = Pr[symbol omitted]) reveals that the N₂ ligand is symmetrically bound in a side-on fashion to both metals. In addition, the N—N bond length of 1.548 (7) Å, the longest bond length ever reported for a dinitrogen complex, indicates that the dinitrogen has been reduced to a N₂⁴⁻ hydrazido ligand. Protonation of the complex with HCl results in a quantitative formation of hydrazine.
Science, Faculty of
Chemistry, Department of
Graduate

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9

Thu, Hung-yat. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetate complexes." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B38027872.

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10

Lock, Philippa Edlyne. "The structures and dynamics of organometallic-arene complexes and bimetallic clusters /." *McMaster only, 2001.

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11

Dann, Sandra Elizabeth. "Preparation and characterisation of high oxidation state compounds of transition metals." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241254.

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12

Capparelli, Mario Vicente. "Structural studies on some nucleotide and nucleoside compounds with transition metals." Thesis, Imperial College London, 1985. http://hdl.handle.net/10044/1/37650.

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13

Dawson, William G. "Ab initio LCAO electronic structure calculations of layered transition-metal compounds." Thesis, University of Bath, 1988. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380362.

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14

Mapolie, Selwyn Frank. "The synthesis and reactivity of binuclear μ-hydrocarbyl complexes of some transition metals." Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/22208.

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The new μ-(l,n)-alkanediyl compounds [(ƞ⁵-C₅R₄Me)Fe(CO)₂ ]₂{μ-(CH₂)n}, (R = H, n = 3 -10 and R =Me, n =3 - 6), [Mn(CO)₅]₂{μ-(CH₂)n} (M = Mn, n = 4-6 and M = Re, n= 3 and 4) have been prepared using essentially two synthetic routes. Thus the iron compounds were synthesized by the reaction of Na[(ƞ⁵-C₅R₄Me)Fe(CO)₂ ] with the appropriate dibromoalkane. The manganese and rhenium compounds on the other hand, were prepared by the decarbonylation of the corresponding diacyl compounds of the type, [M(CO)₅]₂{μ-CO(CH₂)nCO} (M = Mn or Re). These diacyl species in turn were synthesized by the reaction of Na[M(CO)s] with diacyl chlorides. All the new compounds have been fully characterized by microanalysis, infrared, ¹H and ¹³C nmr spectroscopy. The mass spectra of the compounds have been investigated and the fragmentation patterns are discussed and compared with other known polymethylene compounds. An extensive investigation into the reactivity of the new alkanediyl compounds has been carried out. Thus for example the reactivity of the compounds [CpFe(CO)₂]₂{μ-(CH₂)n} with nucleophiles such as tertiary phosphines and isocyanides, yield diacyl compounds of the type [CpFe(CO)L]₂{μ-CO(CH₂)nCO} (Cp = C₅H₄Me or C₅Me₅) and (L = tertiary phosphine or isocyanide). Similar ligand induced CO insertion reactions were observed for the manganese and rhenium alkanediyl compounds. The products from these reactions were characterized using the analytical techniques mentioned earlier. The reactions are discussed and compared with those of mononuclear alkyl compounds of manganese, rhenium and iron. The reactions of some polymethylene bridged compounds with synthesis gas have also been investigated. This reaction is of importance in view of the fact that polymethylene bridged compounds have been implicated in a number of catalytic processes e.g the Fischer- Tropsch reaction. The reaction with synthesis gas was found to yield bifunctional alcohols of the type HO(CH₂)nOH. In a separate study, the binuclear μ-phthaloyl compounds of manganese, rhenium,iron,molybdenum,cobalt and rhodium were prepared and characterized. The phthaloyl compounds of manganese, rhenium and iron were decarbonylated to form the corresponding μ-phenylene compounds. The reactions of some of these compounds with nucleophiles and electrophiles have been studied and the results compared with that of the corresponding mononuclear benzoyl and phenyl compounds.

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15

Ng, Kee-Pui Dennis. "The chemistry of η-cycloheptatrienyl derivatives of molybdenum and tungsten." Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:b41ab51d-7f86-4989-8b34-3d3e06627c9c.

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This thesis describes the synthetic, structural and reactivity studies of η- cycloheptatrienyl-molybdenum and -tungsten chemistry. Chapter 1 presents an overview of the chemistry of η-cycloheptatrienyl derivatives of transition metals, in particular group 6 metals. The functional group properties of the η-cycloheptatrienyl ligand are also discussed. Chapter 2 describes the synthesis of [Mo(η-C₇H₇)(η⁵-C₇H₉)] from Mocl₅ or [MoCl₄(thf)₂], which provides a convenient route to η-cycloheptatrienyl-molybdenum compounds, such as [Mo(η-C₇H₇)LX₂] and [Mo(η-C₇H₇)L₂X], where L = tertiary phosphines or acetonitrile and X = halogen, [NBu₄] [Mo(η-C₇H₇)I₃], [Mo(η-C₇H₇)(η- C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The X-ray crystal structures of [Mo(η-C₇H₇)(MeCN)I₂], [NBu₄][Mo(η-C₇H₇))I₃] and [Mo(η-C₇H₇)(η-C₅H₄Me)] are presented. The compound [Mo(η-C₇H₇))(MeCN)I₂], mixed with Me₃SiCH₂MgCl, is a catalyst for ring-opening polymerisation of norbornene giving trans polymer exclusively. The electron-transfer complexes [Mo(η-C₇H₇)(η-C₅H₄Me)][tcne] and {[Mo(η-C₇H₇))(η- C₅H₅}₂[tcnq]} and the intercalation compound {ZrS₂[Mo(η-C₇H₇)(η-C₅H₄Me)]o.22} are also described. An extension of these synthetic pathways to tungsten is described in chapter 3. Reduction of WCl₆ with sodium amalgam in the presence of cycloheptatriene gives [W(η- C₇H₇)(η⁵-C₇H₉)], which is a precursor to the compounds [W(η-C₇H₇)(MeCN)I₂], [W(η- C₇H₇)(PMe₃)X₂] (X = Br or I), [W(η-C₇H₇)(dmpe)I], [W(η-C₇H₇)(η-C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The [W(η-C₇H₇)(MeCN)I₂] / Me₃SiCH₂MgCI system is an active catalyst for ring opening polymerisation of norbomene. The electronic structures of [W(η-C₇H₇)(η-C₅H₄R)] (R= H or Me) are discussed on the basis of their He I and He II photoelectron spectra. The intercalation of [W(η-C₇H₇)(η-C₅H₄Me)] into ZrS2 is also described. The magnetic properties of the 17-electron compounds [Mo(η-C₇H₇)(MeCN)I₂], [Mo(η-C₇H₇)(PMe₃)I₂], [W(η-C₇H₇)(MeCN)I₂], [W(η-C₇H₇)(PMe₃)I₂] and [W(η-C₇H₇) (PMe₃)I₂] are discussed in chapter 4. They behave as one-dimensional antiferromagnets which was suggested by magnetic model fittings and the crystal structure of [Mo(η-C₇H₇)(MeCN)I₂]. Chapter 5 comprises of two parts. The first part describes a new series of binuclear thiolato-bridged molybdenum complexes [(η-C₇H₃R¹₄)Mo(μ-SR²)₃ Mo- (η-C₇H₃R¹₄)][BF₄] (R¹ = H or Me; R² = Et, Pr, Bu, Ph or CH₂Ph). Dynamic NMR studies reveal that all of these complexes (except for R² = Ph) are fluxional due to inversion at the pyramidal sulfur centre. Cyclic voltammetric studies show that they undergo two reversible one-electron reductions. Second part of this chapter describes the new bridging-imido compound [(η-C₇H₇)Mo(μ-NAr)₂Mo(η-C₇H₇)] (Ar = 2,6- diisopropylphenyl). Chapter 6 discusses the η-l,2,4,6-tetramethylcycloheptatrienyl-molybdenum system. The new η-tetramethylcycloheptatriene molybdenum compounds [M'(η-C₇H₄Me₄- 1,3,5,7)],[M'(η-C₇H₄Me₄-l,2,4,6)] and [M'(η-C₇H₄Me₄-l,3,4,6)], M' = Mo(CO)₃, and new η-tetramethylcycloheptatrienyl-molybdenum compounds [M"(CO)₃]+, [M"(CO)₂C1], [M"(dmpe)Cl], [M"(η-C₆H₅Me)]+ and [M"(acac)(PPh₃)], M" = Mo(η- CC₇H₃Me₄-1,2,4,6), and [Mo(η³-C₇H₃Me₄-l,2,4,6)(dmpe)(CO)₂Cl] are described. Chapter 7 gives the experimental details for the work described in preceeding chapters. Appendix A presents characterising data for all the new compounds and previously unreported data for known compounds. Crystallographic details for the X-ray structure determinations and X-ray powder diffraction data are listed in Appendix B and C respectively.

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16

Wang, Na, and 王娜. "Electronic transitions of transition metal monoboride and monoxides." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/208620.

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17

Amako, Masaaki Brook Michael A. "Synergy of polydimethylsiloxanes and late transition metal complexes." *McMaster only, 2004.

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18

Yigit, Mehmet Veysel. "Design of open hydrogen-bonded frameworks using bis(imidazolium 2,4,6-pyridinetricarboxylate)metal complexes as secondary building units." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0514103-110657.

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19

Baba, Eduard. "N-Heterocyclic Carbenes of the Late Transition Metals: A Computational and Structural Database Study." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4792/.

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A computational chemistry analysis combined with a crystallographic database study of the bonding in late transition metal N-heterocyclic carbene (NHC) complexes is reported. The results illustrate a metal-carbon bond for these complexes, approximately 4% shorter than that of a M-C single bond found in metal alkyl complexes. As a consequence of this result, two hypotheses are investigated. The first hypothesis explores the possibility of multiple-bond character in the metal-carbon linkage of the NHC complex, and the second, considers the change in the hybridization of the carbenoid carbon to incorporate more p character. The latter hypothesis is supported by the results. Analysis of these complexes using the natural bond orbital method evinces NHC ligands possessing trans influence.

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20

Mobbs, B. E. "Arene transition metal complexes in synthesis." Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:4c7030d4-297e-4af8-a622-d5b4963fc0a3.

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This thesis deals with the applications of organopalladium and organochromium chemistry to the functionalisation of the benzopyran ring system, at a variety of oxidation levels. Section I demonstrates the functionalisation of 3-, 6-, and 8-bromochromones via palladium (0) insertion into the C-Br bond. The resultant arylpalladium species are shown to undergo addition to the least substituted end of a variety of olefins including methyl acrylate, acrylonitrile and styrene. Subsequent palladium-hydride elimination leads to overall palladium catalysed vinylation of the chromone and the synthesis of a number of novel compounds. Vinylation occurs regiospecifically at the site of chromone bromination and is shown to allow clean substituent introduction into each of the three sites. The palladium catalysed reaction of 3,6-dibromo-chromone with methyl acrylate leads to vinylation at both the C3 and C6 positions. Carbonylation of the 6-bromochromone in ethanol or butanol leads to the 6-ethyl or 6-butyl esters respectively. The palladium catalysed vinylation of the 6-bromochromone with ethyl vinyl ether leads to a mixture of products from addition of the chromone to either end of the olefin. With p-bromophenol or p-bromo-N,N-dimethylaniline the reaction gives exclusively the acetylated product arising from addition to the more substituted end of the olefin. This change in orientation is rationalised by considering the polarisation of the olefin and the arylpalladium species. Section II demonstrates the functionalisation of chroman and 4-chromanol via coordination to the Cr(CO)₃ moiety. (η⁶-Chroman)Cr(CO)₃ is synthesised and is shown to undergo regiospecific ring deprotonation at C8 under kinetic conditions or regiospecific benzylic deprotonation at C4 under thermodynamic conditions. The resultant anions are quenched with alkyl halides, aldehydes, Eschenmoser's salt and methyl disulphide resulting in selective functionalisation of either site. No mixed products are observed. The uncomplexed arene is shown to be totally unreactive under identical conditions. (η⁶-4-Chromanol)Cr(CO)₃ is synthesised and is shown to undergo regiospecific C8 ring deprotonation by comparison with authentic samples of the C5 and C8 methylated alcohols. Protection of the hydroxyl group as its methyl, t-butyldimethylsilyl or methoxymethyl ethers is found not to alter the regiochemistry of deprotonation. The 4-chromanol t-butyldimethylsilyl and tri-i-propylsilyl ethers are synthesised and coordinated to the metal unit. Cleavage of the silyl ethers is shown to proceed with loss of stereochemistry, indicating C-0 bond cleavage.

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21

Allen, Kevin Dale 1968. "Synthesis and characterization of multiple and metallacyclic imido compounds of the early transition metals." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278101.

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The bis(imido) complex Nb(=NAr)₂Cl(py)₂(Ar=2,6-diisopropylphenyl) reacts with two equivalents of LiNHAr in THF to form [Li(THF)₄)][Nb(=NAr)₂(NHAr)₂] (2). Likewise [Nb(NEt₂)₂Cl₃]₂ reacts with excess LiNHAr in THF to form 2. A similar neutral bis(imide) bis(amide) compound (9) of molybdenum has been made. Experiments are presented that suggest the (tris)imido functional group (Nb(=NAr)₃) - arises via an intermolecular deprotonation of [Nb(=NR)₂(NHR)₂]⁻. Complex 2 reacts with 1 equivalent of ᵗBuLi to form the tris(imide) amide [Li₂(THF)₄][Nb(=NAr)₃(NAr)] (6). Ta(OR)₂Cl₃(OEt₂) (OR=2,6-diisopropylphenoxide) reacts with excess 6-methylquinoline (6MQ) to form (η¹-(N)-6MQ)Ta(OR)₂Cl₃ (10). Compound 10 cannot be reduced to the η²-(N,C) product; however, (η₆-C₆Me₆)Ta(OR)₂Cl reacts with excess 6MQ to form (η²-(N,C)-6MQ)Ta(OR)₂Cl(Et₂O) (11), a precursor to metallacyclic imides and a proposed HDN intermediate. Compound 10 can be reduced to afford an unusual Ta(IV) complex (ηˣ-6MQ)Ta(OR)₂Cl₂ (12).

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22

Shaw, Alan. "Synthesis and reactivity studies on oxo and sulphide compounds of the early transition metals." Thesis, Durham University, 1989. http://etheses.dur.ac.uk/6554/.

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This thesis describes studies directed towards the preparation of new oxo compounds of the early transition metals with a view to delineating some of the complex factors which govern their stability and reactivity. For a number of the types of compound studied, the work has also been extended to analogous sulphide systems in order to provide a contrast with another chalcogenide element and further aid an understanding of the bonding and reactivity of both of these elements in a transition metal enviroment. Chapter 1 highlights the areas of transition metal oxo chemistry of relevance to the general theme of the thesis. Chapter 2 describes the use of the commercially available reagents Me(_3)SiYR (R = alkyl, SiMe(_3); Y = O, S), for rapid, convenient, solution syntheses of transition metal oxohalide and sulphidohalide compounds of molybdenum, tungsten, niobium and tantalum. In addition, this methodology allows the preparation of mixed oxosulphidohalide materials and, in certain cases, intermediate alkoxo(siloxo) halide compounds have been isolated. Chapter 3 describes the synthesis, characterisation and reactivity of a series of mononuclear mono-oxo complexes of molybdenum and tungsten including M(O)(OAr)(_4) [M=W, Ar=2,6-Me(_2)C(_6)H(_3) (DMP), 2,4,6-Me(_3)C(_6)H(_2) (TMP), 2,6-Pr(^i)C(_6)H(_3) (DIPP); M=Mo, Ar=(DMP)], M(_2)(O)(_3)(DMP)(_6) and Mo(O)C1(_2)(DMP)(_2). Attempts to synthesise related mononuclear complexes containing the cis di-oxo moeity are also discussed. Chapter 4 describes the synthesis and reactivity of seven coordinate oxo and sulphidohalide derivatives of niobium and tantalum which exhibit the phenomenon of bond-stretch isomerism. Compounds prepared include Nb(O)Br(_3)(PMe(_3))(_3), Nb(S)X(_3)(PMe(_3))(_3) (X=C1, Br) and Ta(S)C1(_3)(PMe(_3))(_3). The latter three have been characterised by X-ray crystallography. Chapter 5 describes the synthesis and reactivity of half-sandwich oxo compounds of niobium and tantalum. Some of the derivatives prepared include[CpNbC1(_3)](_2)(µ(_2)-O), [CpTaC1(_3)](_2)(|µ(_2)-O) and [Cp*TaC1(_3)](_2)(µ(_2)O). The stability of [Cp*Ta(O)Cl(_2)](_2) has been investigated and the X-ray structure of the trinuclear decomposition product Cp*(_3)Ta(_3)O(_4)C1(_4) is described. Chapter 6 describes the use of alkali metal aryloxides as intercalating agents and the preparation of a series of novel intercalation compounds, of the type W(O)(_2)C1(_2)xM (M = Li, Na and K) which display the properties characteristic of tungsten bronzes. Chapter 7 gives experimental details for chapters 2 6.

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23

Ling, Jie Albrecht-Schmitt Thomas E. "Hydrothermal syntheses, structures, and properties of new iodate and selenite compounds of transition metals, lanthanides, and actinides." Auburn, Ala, 2007. http://repo.lib.auburn.edu/2007%20Fall%20Dissertations/LING_JIE_49.pdf.

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24

Thu, Hung-yat, and 杜鴻溢. "Catalytic C-H bond functionalization reactions catalyzed by rhodium(III) porphyrin, palladium(II) and platinum(II) acetatecomplexes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38798268.

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25

Felton, Solveig. "Tunable Magnetic Properties of Transition Metal Compounds." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5939.

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26

Bojczuk, M. "Carbonyl exhange mechanisms in transition metal compounds." Thesis, University of Kent, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372765.

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27

Pearse, Steven Paul. "Novel routes to binary transition metal compounds." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332071.

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28

Humphrey, Paul Andrew. "A study of transition metal complexes /." Title page, contents and summary only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phh9262.pdf.

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29

Blincko, Stuart. "Novel luminescent compounds for immunoassay." Thesis, City University London, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.255249.

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30

Huang, Xin. "Theoretical studies on transition metal mediated reactions /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202004%20HUANG.

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31

Fullaway, Phillip V. "α-Diimine complexes of transition metals for the polymerisation of lower α-olefins." Thesis, Stellenbosch : University of Stellenbosch, 2005. http://hdl.handle.net/10019.1/2341.

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Thesis (MSc (Chemistry and Polymer Science))--University of Stellenbosch, 2005.
In this study several potential polymerisation catalysts were synthesised. This was accomplished by coordinating α-diimine ligands such as N,N'-diferrocenyldiazabutadiene (DFDAB), N,N'-dimesityldiazabutadiene (DMDAB) as well as the bidentate amine N,N,N',N'-tetramethylethylenediamine (TMEDA), to several transition metals. The multi-step synthesis of N,N'-diferrocenyldiazabutadiene (DFDAB) from ferrocene involved the use of lithiated ferrocene, iodoferrocene, N-ferrocenylphthalimide and aminoferrocene; the latter three were characterised. This ligand was coordinated to the transition metal ions iron(II) and zinc(II) to form Fe(DFDAB)Cl2 and Zn(DFDAB)Cl2 respectively. 1H and 13C NMR, FT-IR and mass spectrometry revealed that the expected product had been synthesised in a useful form. 2,4,6-Trimethylaniline reacted with glyoxal to form N,N'-dimesityldiazabutadiene (DMDAB). The DMDAB ligand was coordinated to the transition metal ions zinc(II) and silver(I) to form Zn(DMDAB)Cl2 and Ag(DMDAB)2 respectively. Characterisation now also include molecular and crystallographic structural determinations by means of X-ray diffractometry. Another N-donor complex, Cr(CO)4(TMEDA), was also prepared by coordinating N,N,N',N'-tetramethyl ethylenediamine (TMEDA) to Cr(CO)5(THF). This was done to give an indication of the activity of low oxidation state complexes in the catalysis of olefin polymerisation. The metal-α-diimine complexes mentioned above were employed in the polymerisation of the monomers ethylene and 1-pentene probably according to a cationic mechanism. High density, high molar mass polyethylene products with narrow polydispersities were obtained. The chromium(TMEDA) complex produced polyethylene exhibiting ultra-high molar mass (> 10 000 kg/mol). The polymerisation of 1-pentene, using the Fe(DFDAB)Cl2 complex, afforded oligo-pentene with a molar mass of ~800 g/mol. After an unsuccessful attempt to prepare the (CO)5Cr=C(OZrCp2Cl)(ferrocenyl) modified Fischer-type carbene complex, the (CO)5Cr=C(OMe)(ferrocene) complex was eventually insolated. Elucidation of its molecular structure was accomplished by X-ray diffractometry. Finally, the DFDAB-ligand was coordinated to Fe2(CO)9 to generate Fe(CO)3(DFDAB) in another attempt to investigate the role of carbonyl groups and also low oxidation state metals in polymerisation reactions [compare to Cr(CO)4(TMEDA) unit above]. The sensitivity of this complex towards moisture and air prevented such action.

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32

Wilson, Duane C. "Synthesis, Structure, And Characterization Of Rare Earth(Iii) Transition Metal Cyanides; Lanthanide(Ii) And Metallocene Amidotrihydroborates." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1230880974.

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33

Broddefalk, Arvid. "Magnetic properties of transition metal compounds and superlattices." Doctoral thesis, Uppsala University, Department of Materials Science, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-535.

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Magnetic properties of selected compounds and superlattices have been experimentally studied using SQUID (superconducting quantum interference device) and VSM (vibrating sample magnetometer) magnetometry, neutron diffraction and Mössbauer spectroscopy measurements combined with theoretical ab initio calculations.

The magnetic compounds (Fe_1-xM_x)₃P, M=Co or Mn have been studied extensively. It was found that Co can substitute Fe up to x=0.37. Increasing the Co content leads to a reduction of the Curie temperature and the magnetic moment per metal atom. Mn can substitute Fe up to x=0.25 while Fe can be substituted into Mn₃P to 1-x=0.33. On the iron rich side, the drop in Curie temperature and magnetic moment when increasing the Mn content is more rapid than for Co substitution. On the manganese rich side an antiferromagnetic arrangement with small magnetic moments was found.

The interlayer exchange coupling and the magnetocrystalline anisotropy energy of Fe/V superlattices were studied. The coupling strength was found to vary with the thickness of the iron layers. To describe the in-plane four-fold anisotropy, the inclusion of surface terms proved necessary.

The in-plane four fold anisotropy was also studied in a series of Fe/Co superlattices, where the thickness of the Co layers was kept thin so that the bcc structure could be stabilized. Only for samples with a large amount of iron, the easy axis was found to be [100]. The easy axis of bulk bcc Co was therefor suggested to be [111].

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34

Decker, Stephen Andrew. "Modeling transition metal compounds, testing, development, and applications." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0010/NQ59947.pdf.

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35

Eshuis, Johan Jan Willem. "Catalytic olefin polymerization with early transition metal compounds." [S.l. : [Groningen : s.n.] ; University of Groningen] [Host], 1991. http://irs.ub.rug.nl/ppn/.

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36

Pavitt, David. "Few-layer transition metal chloride graphene intercalation compounds." Thesis, University of London, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603531.

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Few-layer transition metal chloride graphene intercalation compounds have becJI fabricated by the mechanical exfoliation of graphite intercalation compounds (GTCs) containing CoC12 , NiCh, CuCl2 , MnCh and FeC13 . The number of graphene layers and the distribution of the intercalate in the few-layer graphene intercalation compounds (FLGICs) have been characterised using the optical contrast of the FLGICs against the Si02 substrate and the G-peak of the Raman spectrum. FLGICs containing CL single intercalate layer surrounded by two graphene layers have been fabricated and characterised, which are an ideal system to study 2D magnetic phase transitions.

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37

Smith, Deborah Jane. "Solid state NMR studies of transition metal compounds." Thesis, University of Oxford, 1986. http://ora.ox.ac.uk/objects/uuid:e2c88c27-a264-4325-8276-00bf305d0ded.

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This thesis is concerned with a systematic study of phosphine-containing transition metal complexes and cluster compounds by high resolution solid state nmr spectroscopy, using the techniques of magic angle spinning and cross polarisation. Previous work has indicated the potential of the solid state nmr technique to investigate a variety of materials: this is considered in the introduction to this thesis, and the reasons for choosing to study transition metal phosphine compounds are discussed. The analysis of spinning sidebands to obtain the principle values of the shielding tensor is examined to determine how well the calculated values represent the true values. Simulations of slow MAS spectra are proposed as a means of testing and refining the calculated tensor components before attempting to correlate the shielding with structural parameters. The results of a study of a series of crystalline phosphine-containing complexes and clusters are presented. The spectra are interpreted on the basis of the known crystal structures: in some cases separate resonances can be resolved in the solid state spectra from the distinct phosphine environments of a cluster framework, and from inequivalent sites in the unit cell. Information is obtained from the isotropic shifts, scalar couplings and the chemical shift anisotropy. Many of the compounds are fluxional in solution, some even at low temperature: whereas a number of these are found to be rigid in the solid state at room temperature, some of the crystalline compounds retain their fluxionality. Investigations of the species formed when transition metal carbonyl clusters are anchored to oxide supports were carried out. These show the presence of several distinct phosphorus-containing species, some of which are not consistent with the simple attachment of the cluster to the surface. The unique importance of the solid state technique is demonstrated in the study of these supported species.

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Ko, Yuen Ting. "Search for unconventional superconductivity in transition metal compounds." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609099.

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39

Rai, Chaudhuri Anjana. "Electronic structure and bond energy trends in silicon-hydrogen and germanium-hydrogen bond activation by transition metals." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184731.

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The electronic structure factors that control Si-H and Ge-H bond activation by transition metals are investigated by means of photoelectron spectroscopy. Molecular orbital calculations are also used to gain additional insight into the orbital interactions involved in bond activation. The complexes studied have the general molecular formula (η⁵-C₅R'₅)Mn(CO)(L)HER₃, where R' is H or CH₃, L is CO or PMe₃, E is Si or Ge and R is Ph or Cl. These compounds are interesting models for catalysts in industrial processes like hydrosilation. The compounds display different stages of interaction and "activation" of the E-H bonds with the metal. One purpose is to measure the degree of Mn, Si, H 3-center-2-electron bonding in these complexes. The three-center interaction can be tuned by changing the substituents on Si, methylating the cyclopentadienyl ring, changing the ligand environment around the metal and substituting Si with Ge. The degree of activation is measured by observing the shifts in the metal and ligand ionizations relative to starting materials and free ligand in the photoelectron spectrum. Changing the substituent on Si extensively changes the degree of activation. Photoelectron spectral studies on (η⁵-C₅H₅)Mn(CO)₂HSiPh₃ show this to be a Mn(I) system. Progressive methylation of the cyclopentadienyl ring increases the electron richness at the metal center with no substantial effect on the degree of activation. Substitution on the metal (PMe₃ for CO) is less able to control the electronic structure factors of activation than the substitution on the Si atom. The magnitude of Ge-H bond activation is found to be of the same order as the Si-H bond activation for analogous compounds as found by studying (η⁵-C₅H₅)Mn(CO)₂HGePh₃, (η⁵-CH₃C₅H₄)Mn(CO)₂HGePh₃ and (η⁵- C₅(CH₃)₅)Mn(CO)₂HGePh₃ complexes by photoelectron spectroscopy. The photoelectron spectra of CpFe(CO)₂SiCl₃ and CpFe(CO)₂SiMe₃ were measured to study the electron charge shift from the metal to the ligand in these complexes as compared to CpMn(CO)₂HSiR₃ complexes. The photoelectron spectroscopic studies include numerous perturbations of the ligand and metal center to observe the extent of bond interaction and remain one of the best techniques to detect activation products.

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Liddell, Michael John. "Studies in organo-transition metal chemistry /." Title page, contents and summary only, 1989. http://web4.library.adelaide.edu.au/theses/09PH/09phl712.pdf.

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41

Ruiz-Morales, Yosadara. "The calculation and interpretation of NMR chemical shifts in compounds of transition metals and heavy elements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ31071.pdf.

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42

Vasbinder, Michael John. "Oxidations of organic and inorganic substrates by superoxo-, hydroperoxo-, and oxo-compounds of the transition metals." [Ames, Iowa : Iowa State University], 2006.

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43

Goje, Tesfai Tedros. "Determination of aminopolycarboxylate complexes of transition metal (Mn²⁺, Cu²⁺ and Fe³⁺) in pulp by capillary zone electrophoresis (CZE-DAD)." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49906.

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Thesis (MSc)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: The determination of the concentrations of the transition metals Mn2 +, Cu2 + and Fe3 + in various types of pulps was carried out using a combination of chelation with Ethylenediaminetetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (S,SEDDS) and capillary zone electrophoresis (CZE) coupled with diode array uvdetection. The metals were found to be inhomogeneously distributed in the pulps, and therefore a relatively large (20 gms) pulp samples were taken for analysis. Heating the pulp samples at 45°C with stirring for three hours was used to leach the metals into an aqueous phase for complexation with the ligands. Leaching with EDTA enabled the quantitative determination of 0.0091,0.0048 and 0.0014 mM Cu2 + and 0.0088, 0.0012 and 0.0016 mM Mn2 + in the three types of pulps analyzed respectively while detection of Fe3 + was not possible using EDTA. The use of [S,S-EDDS] as the leaching agent on the other hand enabled the quantitative determination of 0.0041, 0.0036 and 0.0031 mM Cu2+ and 0.0024, 0.0018 and 0.0047 mM Fe3+ in the three types of pulps analyzed respectively while determination of Mn2 + was not possible using [S,S-EDDS] as the leaching agent. [S,S-EDDS] was generally better in complexing iron and copper than EDTA. The leaching procedure employed and the detectors response to specific analytes formed were found to be the most important factors in the analysis of the metals in pulp.
AFRIKAANSE OPSOMMING: Die konsentrasies van die oorgangsmetale Mn2 +, Cu2 + and Fe3 + in verskeie tipes pulp is bepaal met behulp van 'n kombinasie van kelasie met etileendiamientetra-asynsuur (EDTA) en etileendiamiendisuksiensuur (S,S-EDDS) en kapillêre elektroforese (CE) gekoppel met UV-deteksie. Daar is bevind dat die metale oneweredig versprei is in die pulp monsters, en gevolglik is relatiewe groot (20 g) monsters gebruik vir die analiese. Die metale is ge-ekstraeer deur kompleksasie met die kelasie-agente in die water-fase, deur die pulp monsters vir drie uur te roer by 45°C. Ekstraksie met EDT A is gebruik om 0.0091,0.0048 en 0.0014 mM Cu2 + en 0.0088,0.0012 and 0.0016 mM Mn2 + in drie tipes pulp te bepaal, terwyl Fe3 + nie waargeneem is met behulp van EDTA nie. Deur [S,S-EDDS] te gebruik as ekstraksie-agent, is 0.0041, 0.0036 en 0.0031 mM Cu2+ en 0.0024, 0.0018 en 0.0047 mM Fe3+ in die drie tipes pulp waargeneem. Die analise van Mn2 + was nie moontlik met die metode nie. Daar is gevind dat die keuse van ekstraksie metode en die detektor-sensitiwiteit vir spesifieke metale die mees bepalende faktore in die analise van metale in pulp monsters is. EDDS was 'n beter keiaat vir Fe3 + en Cu2 + as EDTA.

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44

James, Alan Jay. "Metal thiazenes, bulky phosphines, group 11 acetylides and nickel acenaphthalenes /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3074411.

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45

Meade, Thomas Joseph. "Inclusion complexes of molecular transition metal hosts /." The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487262513406675.

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46

Yu, Yaqin Albrecht-Schmitt Thomas E. "Studies on the structures and properties of bimetallic uranium transition metal and hybrid organic-inorganic compounds." Auburn, Ala, 2009. http://hdl.handle.net/10415/1748.

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47

Peterson, Charles Campbell. "Accurate Energetics Across the Periodic Table Via Quantum Chemistry." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc822822/.

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Greater understanding and accurate predictions of structural, thermochemical, and spectroscopic properties of chemical compounds is critical for the advancements of not only basic science, but also in applications needed for the growth and health of the U.S. economy. This dissertation includes new ab initio composite approaches to predict accurate energetics of lanthanide-containing compounds including relativistic effects, and optimization of parameters for semi-empirical methods for transition metals. Studies of properties and energetics of chemical compounds through various computational methods are also the focus of this research, including the C-O bond cleavage of dimethyl ether by transition metal ions, the study of thermochemical and structural properties of small silicon containing compounds with the Multi-Reference correlation consistent Composite Approach, the development of a composite method for heavy element systems, spectroscopic of compounds containing noble gases and metals (ArxZn and ArxAg+ where x = 1, 2), and the effects due to Basis Set Superposition Error (BSSE) on these van der Waals complexes.

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48

Polyakov, Andrey. "Fermi-surface investigations of rare-earth transition-metal compounds." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-113653.

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The interplay of partially filled d- or f-electron shells with conduction-band electrons is a key ingredient in new rare-earth transition-metal compounds for the emergence of unusual electronic and magnetic properties. Among which unconventional superconductivity is one of the most studied. Despite many years of intensive experimental investigations and plenty promising theoretical models, unconventional superconductivity still remains hotly debated a very rich topic. One of the fundamental unsolved problems for condensed-matter physicists is the mechanism that causes the electrons to form anisotropic superconductivity. Since electrons in the vicinity of the Fermi level are primarily responsible for superconductivity, in order to better understand the mechanism giving rise to this phenomenon and the origin of complex forces between correlated electrons, knowledge of the Fermi surface and band selective effective mass is essential. Of the many techniques used to study electronic band-structure properties, measurements of quantum oscillations in the magnetization, so-called de Haas-van Alphen (dHvA) effect, in combination with band-structure calculations is the traditional proven tool for studying Fermi-surface topology and quasiparticle effective mass. In the present work, electronic structure and Fermi-surface properties of Ybsubstituted heavy fermion superconductor CeCoIn5 and iron based ternary phosphides LaFe2P2 and CeFe2P2 have been investigated by means of dHvA measurements. For these measurements, capacitive cantilever-torque magnetometry was utilized. In Ce1−xYbxCoIn5, the evolution of the Fermi surface and effective mass was studied as a function of Yb concentration. The observed topology change is consistent with what is expected from the band-structure calculations. For a small Yb concentration, x = 0.1, the band-structure topology and the effective masses remain nearly unchanged compared to CeCoIn5. This contrasts clearly modified Fermi surfaces and light, almost unrenormalized effective masses for x = 0.2 and above. For LaFe2P2 and CeFe2P2, the obtained effective masses are light. Good agreement between the calculated and measured dHvA frequencies was identified only for LaFe2P2. However, for CeFe2P2 strong disagreement was observed. Moreover, different CeFe2P2 single crystals reveal different experimental results. In order to reconcile the results of the dHvA measurements and density-functional-theory calculations more work is necessary.

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49

Llewellyn, Simon. "Acyl carbonyl transition metal compounds : their homologation and hydrogenation." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433556.

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50

Aliabadi, Azar. "ESR and Magnetization Studies of Transition Metal Molecular Compounds." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-195440.

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Molecule-based magnets (molecular magnets) have attracted much interest in recent decades both from an experimental and from a theoretical point of view, not only because of their interesting physical effects, but also because of their potential applications: e.g., molecular spintronics, quantum computing, high density information storage, and nanomedicine. Molecular magnets are at the very bottom of the possible size of nanomagnets. On reducing the size of objects down to the nanoscale, the coexistence of classical properties and quantum properties in these systems may be observed. In additional, molecular magnets exist with structural variability and permit selective substitution of the ligands in order to alter their magnetic properties. Therefore, these characteristics make such molecules suitable candidates for studying molecular magnetism. They can be used as model systems for a detailed understanding of interplay between structural and magnetic properties of them in order to optimize desired magnetic properties. This thesis considers the investigation of magnetic properties of several new transition metal molecular compounds via different experimental techniques (continuous wave electron spin resonance (CW ESR), pulse ESR, high-field/high-frequency ESR (HF-ESR) and static magnetization techniques). The first studied compounds were mono- and trinuclear Cu(II)-(oxamato, oxamidato)/bis(oxamidato) type compounds. First, all components of the g-tensor and the tensors of onsite ACu and transferred AN HF interactions of mononuclear Cu(II)- bis(oxamidato) compounds have been determined from CW ESR measurements at 10 GHz and at room temperature and pulse ELDOR detected NMR measurements at 35 GHz and at 20 K. The spin density distributions of the mononuclear compounds have been calculated from the experimentally obtained HF tensors. The magnetic exchange constants J of their corresponding trinuclear compounds were determined from susceptibility measurements versus temperature. Our discussion of the spin density distribution of the mononuclear compounds together with the results of the magnetic characterization of their corresponding trinuclear compounds show that the spin population of the mononuclear compounds is in interplay with the J values of their corresponding trinuclear compounds. The second studied compounds were polynuclear Cu(II)-(bis)oxamato compounds with ferrocene and ferrocenium ligands. The magnetic properties of these compounds were studied by susceptibility measurements versus temperature to determine J values. In addition, the ESR technique is used to investigate the magnetic properties of the studied compounds because they contain two different magnetic ions and because only the ESR technique can selectively excite different electron spin species. These studies together with geometries of the ferrocenium ligands determined by crystallographic studies indicate that the magnetic interaction between a central Cu(II) and a Fe(III) ions changed from the antiferromagnetic coupling to the ferromagnetic coupling when a stronger distortion of the axial symmetry in the feroccenium cation exists. Therefore, the degree of the distortion of the feroccenium cation is a control parameter for the sign of the interaction between the central Cu(II) ion and the Fe(III) spins of the studied compounds. The last two studied molecular magnets were a binuclear Ni(II) compound (Ni(II)-dimer) and a cube-like tetranuclear compound with a [Fe4O4]-cube core (Fe4-cube). HF-ESR measurements enabled us to determine the g-factor, the sign, and the absolute value of the magnetic anisotropy parameters. Using this information together with static magnetization measurements, the J value and the magnetic ground state of the studied compounds have been determined. In Ni(II)-dimer, two Ni(II) ions, each having a spin S = 1, are coupled antiferromagnetically that leads to a ground state with total spin Stot = 0. An easy plane magnetic anisotropy with a preferable direction for each Ni(II) ion is found. For Fe4-cube, a ground state with total spin Stot = 8 has been determined. The analysis of the frequency dependence and temperature dependence of HF-ESR lines reveals an easy axis magnetic anisotropy (Dcube = -22 GHz (-1 K)) corresponding to an energy barrier of U = 64 K for the thermal relaxation of the magnetization. These results indicate that Fe4-cube is favorable to show single molecular magnet (SMM) behavior.

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Dissertations / Theses on the topic 'Transition metals and their compounds'

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