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51 Miller, Joel Steven; Epstein, Arthur J.Dynamic spin fluctuations in the molecular ferromagnet (DMeFc)(TCNE)The static and dynamic magnetic properties of the molecular ferromagnet decamethylferrocenium tetracyanoethenide (DMeFc)(TCNE) are studied via the muon-spin-relaxation technique. Spontaneous order is observed in the ferromagnetic ground state below 5 K, while the muon-spin-relaxation rate in the par...Magnetic; Magnetization; Paramagnetic2001
52 Miller, Joel Steven; Epstein, Arthur J.Effect of disorder on the linear and nonlinear magnetic susceptibilities of two manganeseporphryin-based magnetsWe analyze the effects of disorder on the magnetic properties of two manganeseporphyrins, [MnTPP][TCNE] •. x(o-DCB) and [MnTPP][TCNE] . • y(o-Xy) and (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene, o-Xy=o-xylene, o-DCB=o-dichlorobenzene, x<_3,y<_1). We present data for the in- ...Magnetization; Ferrimagnetic; Spins1997
53 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Cr+ with H2, HD, and D2The reactions of atomic chromium ions with H2 , HD, and D2 are examined using guided ion beam tandem mass spectrometry. The ground electronic state (6S) is found to react inefficiently. The thresholds of these data are analyzed to yield a 0 K bond dissociation energy for CrH+ of 1.37 ± 0.09 eV (31...Chromium ions; Hydrogen; Deuteride; Bond energy1987
54 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Mn+ with H2, HD and D2Reactions of several electronic states of Mn+ with H2, HD, and D2 have been examined using guided ion beam mass spectroscopy. The excitation function for the ground state of Mn+ ( 75) has two regions: one of very low reactivity at threshold and another more efficient pathway at higher energies. In ...Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Endothermic reactions; Metal ions; Manganese; Hydrogen1986
55 Miller, Joel Steven; Epstein, Arthur J.Effect of solvent on the magnetic properties of the high-temperature V[TCNE]x molecule-based magnetThe different magnetic behaviors of the V[TCNE]x (TCNE=tetracyanoethylene) magnet prepared via the reaction of TCNE and V(CO)6 in CH2Cl2 and the solvent-free chemical vapor deposition (CVD) of TCNE and V(CO)6 onto a glass substrate were determined. It was shown that the presence of noncoordinating C...Magnetization; Molecule2001
56 Miller, Joel StevenEffect of thermal annealing on the ferrimagnetic behavior and ordering of the [MnTXPP]+[TCNE].-.solv (X=F, Cl, Br, I; solv = PhMe, CH2Cl2) family of magnets+5,10,15,20-Tetrakis(4-fluorophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTFPP][TCNE], 1F, 5,10,15,20-tetrakis(4-bromophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTBrPP][TCNE], 1Br, and 5,10,15,20-tetrakis(4-iodophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTIPP][T...Magnetic; Coupling2000
57 Miller, Joel Steven; Epstein, Arthur J.Elastic properties of (N(CH3)3H) (I) (TCNQ)We present the results of a study of the temperature dependence of the Young's modulus and internal friction of (N(CH3 )3H)(I)(TCNQ). The Young's modulus was measured in a direction parallel to the TCNQ (tetracyanoquinodimethane) stacking axis using a vibrating reed technique. The results confirmed ...Metal-like, Conductivity, Magnetic1979
58 Armentrout, Peter B.Electron impact ionization cross section of metastable N2(A Σu+)Extensive studies of electron impact cross sections have been carried out both experimentally and theoretically for a number of ground state atoms and molecules.1 In general, as the electron energy is increased, such cross sections rise from a threshold at the ionization potential to a peak at an e...Ion beam; Nitrogen1981
59 Morse, Michael DavidElectron spin resonance investigation of Sc?+ in neon matrices and assignment of its ground electronic state as X ???. comparison with theoretical calculationsThe discandium radical cation, Sc+2 , has been isolated in neon matrices at 4 K and studied by electron spin resonance (ESR) spectroscopy and theoretical methods. It was produced by the x-irradiation of neon matrix samples containing neutral ScZ which was formed by trapping the products generated fr...1993
60 Morse, Michael DavidElectron-spin resonance studies of the titanium cation (Ti+,3d?, ?F) in rare gas matrices at 4 K: A crystal field interpretationElectron-spin resonance studies of laser-ablated titanium metal isolated in neon and argon display an intense feature which exhibits a symmetric, narrow line and a large matrix-dependent g shift. On the basis of a number of experiments, this is assigned to a matrix isolated 3d3,4F Ti+ ion in an octa...1996
61 Wight, Charles Albert; Anderson, Richard BryanElectronic publication of theses and dissertationsFor many years, the university has required its doctoral students to print and publish their dissertations. After a dissertation has been approved for release by the Graduate School thesis editors and the student has been approved for graduation, the university sends one copy of the manuscript to Pr...Electronic publication; Theses; Dissertations2010
62 Morse, Michael DavidElectronic spectroscopy and electronic structure of diatomic CrCOptical spectra of jet-cooled diatomic CrC have been recorded in the near infrared region using resonant two-photon ionization spectroscopy combined with mass-selective detection of the resulting ions. Several weak transitions have been observed, along with one relatively strong band near 842 nm. Ro...2010
63 Morse, Michael DavidElectronic structure of the 4 d transition metal carbides: dispersed fluorsecence spectroscopy of MoC, RuC, and PdCDispersed fluorescence studies of the diatomic molecules MoC, RuC, and PdC are reported. New states identified in MoC and RuC are the [...]2??12??, ?,??? states and the [...]2??12??, ??? state, respectively. Five states are observed by dispersed fluorescence in PdC. The ground state is found to be [...2011
64 Morse, Michael DavidElectronic structure of the 4d transition metal carbides: dispersed fluorescence spectroscopy of MoC, RuC, and PdCDispersed fluorescence studies of the diatomic molecules MoC, RuC, and PdC are reported. New states identified in MoC and RuC are the [...]2?112?1, 3,1?2 states and the [...]2? 312?1, 1?2 state, respectively. Five states re observed by dispersed fluorescence in PdC. The ground state is found to be [...2001
65 Armentrout, Peter B.Endothermic reactions of uranium ions with N2, D2, and CD4The assessment of new technology for isotope separation has revived an interest in the spectroscopy, properties, and reactions of uranium and its compounds. Newer methods which have been demonstrated include the use of lasers to selectively excite a particular uranium isotope with subsequent chemic...Uranium ions; Nitrogen1977
66 Armentrout, Peter B.Energetics and dynamics in the reaction of Si+ with SiF4. Thermochemistry of SiFx and SiFx+ (x=1,2,3)The title reaction is studied using guided ion beam mass spectrometry. Absolute reaction cross sections are measured as a function of kinetic energy from thermal to 40 eV, and three endothermic product channels are observed. The dominant SiF+ + SiF3 channel is only slightly endothermic, while the ...Silicon fluoride; Ion-molecule reactions; Kinetic energy; Threshold behavior; Endothermic reactions1988
67 Armentrout, Peter B.Energy dependence, kinetic isotope effects, and thermochemistry of the nearly thermoneutral reactions of N+(3P) + H2(HD, D2) → NH+(ND+) + H(D)The reactions of N + (3P) ions with H2 , HD, D2 are examined using guided ion beam tandem mass spectroscopy. Absolute reaction cross sections are measured from near thermal energies to 30 eV relative energy. The low energy cross section behavior is analyzed using empirical threshold models and ph...Thermoneutral reactions; Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Phase space theory1987
68 Poulter, Charles DaleEnzymes encoded by the farnesyl diphosphate synthase gene family in the big sagebrush Artemisia tridentata ssp. spiciformisFarnesyl diphosphate synthase catalyzes the sequential head-to-tail condensation of two molecules of isopentenyl diphosphate with dimethylallyl diphosphate. In plants the presence of farnesyl diphosphate synthase isozymes offers the possibility of differential regulation. Three full-length cDNAs enc...Amino Acid Sequence; Base Sequence; Molecular Sequence Data2003-08-22
69 Miller, Joel Steven; Epstein, Arthur J.Evidence for solitons in conducting organic charge-transfer crystalsMagnetic susceptibility of (N-methylphenazinium)x(phenazine)(1-x (tetracyanoquinodimethanide) [(NMP)x(Phen)1-x(TCNQ)] shows the formation of defect states for 0.5<x<0.54. Diffuse x-ray scattering and g-value studies indicate that these defects are solitons formed in the highly correlated quasi-one-...TCNQ; X-ray scattering1982
70 Miller, Joel StevenFar-infrared powder spectrum of (N(CH3)3D)(I)(TCNQ)We present the powder absorption spectrum of (TMA)(I)(TCNQ) in the far-infrared as a function of temperature. Below 160 K new absorption features appear and others increase in intensity. This behaviour supports the electron- neutron-diffraction evidence of a distortion on the TCNQ chains below the f...Conductivity, Crystals, Electrons1983
71 Miller, Joel StevenFar-infrared properties of trimethylammonium iodide tetracyanoquinodimethaneWe present the powder absorption spectrum of (TMA) (I)(TCNQ) in the far-infrared as a function of temperature. Below 16 K new absorption features appear and others increase in intensity. This behaviour supports the electron and neutron diffraction evidence of a distortion on the TCNQ chains below...Trimethylammonium iodide tetracyanoquinodimethane; TCNQ1983
72 Poulter, Charles DaleFarnesyl diphosphate synthetase: molecular cloning, sequence, and expression of an essential gene from Saccharomyces cerevisiaeFarnesyl diphosphate (FPP) synthetase is a key enzyme in isoprenoid biosynthesis which supplies C15 precursors for several classes of essential metabolites including sterols, dolichols, and ubiquinones. The structural gene for FPP synthetase was isolated on a 4.5-kilobase EcoRI genomic restriction f...Genetics; Transferases; Dimethylallyltranstransferase/biosynthesis1989-11-15
73 Poulter, Charles DaleFarnesyl pyrophosphate synthetase. Mechanistic studies of the 1'-4 coupling reaction with 2-fluorogeranyl pyrophosphate.The mechanism of the 1'-4 coupling reaction between isopentenyl pyrophosphate and geranyl pyrophosphate catalyzed by farnesyl pyrophosphate synthetase from porcine liver was studied with the allylic substrate analogue 2-fluorogeranyl pyrophosphate. 2-Fluorogeranyl pyrophosphate is an alternate subst...Kinetics; Liver; Mass Spectrometry; Organophosphorus Compounds; Protein Binding1978-10-25
74 Miller, Joel StevenFerrimagnetic ordering of a methylthio-substituted planar porphyrin based electron transfer salt, octakis(2,3,7,8,12,13,17,18-methylthio)porphyrinatomanganese(III) tetracyanoethanideThe direct redox reaction between tetracyanoethylene (TCNE) and a planar porphyrinatomanganese(II), octakis(2,3,7,8,12,13,17,18-methylthio)porphyrinatomanganese(II), MnIIOMTP, produced a polymeric electron transfer salt (ETS), that has been structurally and magnetically characterized. The ETS belon...Magnetic; Temperature; Coupling2000
75 Miller, Joel StevenFerrimagnetic ordering of one-dimensional N,N'-dicyanoquinone diimine (DCNQI) electron transfer salts with porphyrinatomanganese(II)*The redox reaction between N,N'-dicyanoquinone diimines (DCNQIs) and porphyrinatomanganese(II) produced electron transfer salts (ETSs), [MnIIITMesP]+[DMeO-DCNQI]-. 1 (MnIIITMesP=meso-tetrakis(2,4,6- trimethylphenyl)porphyrinatomanganese(III), DMeO-DCNQI=2,5-dimethoxy-N,N'-dicyanoquinone diimine) an...Transitions; Interactions; Magnetic2001
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