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76 Morse, Michael DavidOptical spectroscopy of jet-cooled NiSiThe electronic states of gaseous diatomic NiSi have been investigated using the combined techniques of resonant two-photon ionization spectroscopy, dispersed fluorescence spectroscopy, and density functional computations. A single electronic band system, designated as the [8.0]1?X 1?+ system, has be...2003
77 Armentrout, Peter B.Translational energy dependence of O+(4S) + N2 → NO+ + N from thermal energies to 30 eV c.m.Guided ion beam mass spectrometry is used to examine the kinetic energy dependence of the reaction of ground state atomic oxygen ion with molecular nitrogen. An 0 + (4S) source which produces less than 0.06% excited states is described. Cross sections for the NO+ + N product channel decrease with...Ion-molecule reactions; Translational energy; Threshold behavior; Endothermic reactions; Nitrogen; Oxygen1987
78 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
79 Miller, Joel Steven; Epstein, Arthur J.Molecule-based magnets - an overviewMolecule-based* magnets are a broad, emerging class of magnetic materials that expand the materials properties typically associated with magnets to include low density, transparency, electrical insulation, and low-temperature fabrication, as well as combine magnetic ordering with other proper...Spin; Magnetization; Magnetic ordering2000
80 Miller, Joel Steven; Epstein, Arthur J.Anomalous relaxation in a quasi-one-dimensional fractal cluster glassThe low-temperature spin glass state of the quasi-1D organic-based magnet [MnTPP]+[TCNE]- .x(1,3-C6H4Cl2) has unusually long relaxation times due to frustration induced by dipole-dipole interactions between fractal spin clusters. This long relaxation is investigated with in-field relaxation measurem...Sweep rate; Bifurcation; Magnetization2004
81 Miller, Joel StevenFormation of a zwitterionic donor-acceptor compound based on N,N,N',N'-tetramethly-p-phenylenediamine and 7,7,8,8-tetracyanoperfluoro-p-quinodimethaneThe reaction of the donor N,N,N',N'- tetramethyl-p-phenylenediamine (TMPD) with the acceptor 7,7,8,8-tetracyanoperfluoro-p-quinodimethane (TCNQF4) has led to the isolation of a novel type of zwitterionic donor-acceptor compound whose structure has been determined by X-ray crystallography.Ccrystals; Single bond1988
82 Voth, Gregory AlanMultiscale coarse-graining of the protein energy landscapeA variety of coarse-grained (CG) models exists for simulation of proteins. An outstanding problem is the construction of a CG model with physically accurate conformational energetics rivaling all-atom force fields. In the present work, atomistic simulations of peptide folding and aggregation equilib...2010-06-24
83 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
84 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
85 Morse, Michael DavidSpectroscopy of AlAr and AlKr from 31 000 cm-1 to the ionization limitSpectra of jet-cooled AlAr and AlKr have been collected over the range from 31 000 cm -? to the ionization limit, using the technique of resonant two-photon ionization spectroscopy with mass spectrometric detection. Adiabatic ionization potentials have been accurately measured for both molecules, an...1992
86 Morse, Michael DavidResonant two-photon ionization spectroscopy of LiCuJet-cooled LiCu has been investigated using resonant two-photon ionization spectroscopy. A long vibrational progression was observed and identified as the [20.5] 1?+? X 1?+ band system. Ten bands of the system were rotationally resolved for 7Li63Cu, giving bond lengths of r0=2.2618(3) ? for the X 1?...1997
87 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
88 Morse, Michael DavidTwo-photon ionization spectroscopy and all-electron ab initio study of LiCaResonant two-photon ionization spectra of LiCa have been obtained from a laser vaporization, supersonic expansion source. The ground state of the molecule is confirmed to be X 2?+. Three band systems have been observed near 15 282, 19 310, and 22 250 cm-1 and the upper states have been assigned as 2...1998
89 Morse, Michael DavidFirst spectroscopic investigation of the 4 d transition metal monocarbide MoCThe first optical spectroscopic investigation of MoC has revealed a complicated vibronic spectrum consisting of about 35 bands between 17 700 and 24 000 cm-1. Analysis has shown the ground state to be the ?=0+ spin?orbit component of a 3?- state that derives from a 10?211?25rr42d 2 configuration. Th...1998
90 Armentrout, Peter B.Guided ion beam and theoretical studies of the reaction of Ru+ with CS2 in the gas-phase: thermochemistry of RuC+, RuS+, and RuCS+Abstract: The gas-phase reactivity of the atomic transition metal cation, Ru+, with CS2 is investigated using guided-ion beam mass spectrometry (GIBMS). Endothermic reactions forming RuC+, RuS+, and RuCS+ are observed. Analysis of the kinetic energy dependence of the cross sections for formation of ...2010
91 Miller, Joel StevenConvenient synthesis of C5(CD3)5H. synthesis and characterisation of Fe{n5-C5(CD3)5}2The large scale synthesis of deuterio(pentamethylcyclopentadiene), C5(CD3)5H ([2H30]Cp*H), and subsequent synthesis of [2H30][Fe(n|-Cp*)2] is described, together with i.r., Raman, and solid state 2H n.m.r. spectroscopic characterisation.Organometallic; Catalytic1988
92 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
93 Poulter, Charles Dale(S)-Geranylgeranylglyceryl phosphate synthase. Purification and characterization of the first pathway-specific enzyme in archaebacterial membrane lipid biosynthesisThe first pathway-specific step in the biosynthesis of the core membrane diether lipids in archaebacteria is the alkylation of the primary hydroxyl group in (S)-glyceryl phosphate by geranylgeranyl diphosphate. The reaction is catalyzed by (S)-3-O-geranylgeranylglyceryl phosphate ((S)-GGGP) synthase...Polyacrylamide gel; Molecular weight1993-10-15
94 Armentrout, Peter B.Thermochemistry of the activation of N2 on iron cluster cations: guided ion beam studies of the reactions of Fen+ (n=1-19) with N2The kinetic energy dependences of the reactions of Fen + (n=1-19) with N2 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-15 eV. In addition to collision-induced dissociation forming Fem + ions, which dominate the product spectra, a variety of FemN2+ and FemN+ p...Metal clusters; Iron ions; Dinitrogen; Endothermic reactions; Collision-induced dissociation; Bond energies2006
95 Miller, Joel StevenNovel coordination of dicyanamide, [N(CN)2]-: preferential binding of the amide nitrogenCoII[N(CN)2]2(H2BiIm)2, 1, and {CoII[N(CN)2](H- 2BiIm)2}Cl, 2 (H2BiIm = 2,2'-biimidazole) have been structurally, spectroscopically, and magnetically characterized with both containing dicyanamides bound in unprecedented manners; namely, solely via the amide nitrogen for 1, and via an imide N form...Magnetic; Dicyanamide; Electron2002
96 Morse, Michael DavidThe 846 nm A? ???u ? ??? band system of jet-cooled V?The 846 nm band system of jet-cooled 5?V2 has been recorded using resonant two-photon ionization spectroscopy, and is assigned as the A ? 3?u- +X ??g- band system. Both the ?'= 1u? ?" = 1g and ?'= Ou+ ??? = 0g+ subbands of the O-O band have been rotationally resolved and analyzed. Although the trans...1992
97 Miller, Joel Steven; Epstein, Arthur J.Anomalous charge transport phenomena in the molecular-based magnet V(TCNE)x.y(solvent)We present charge transport studies on recently developed molecular-based magnets V(TCNE)x. y(solvent) (TCNE= tetracyanoethylene) which show local magnetic ordering at temperatures, T, as high as 400 K. V(TCNE), .y(solvent) prepared from the solvent CH2Cl2 has o(300 K) - 10-3 S/cm, and that prepar...Frequency; Conductivity; Spin1993
98 Armentrout, Peter B.Reaction of Cu+ with dimethoxyethane: competition between association and multiple dissociation channelsThe reaction of Cu1 with dimethoxyethane (DXE) is studied using kinetic-energy dependent guided ion beam mass spectrometry. The bimolecular reaction forms an associative Cu1(DXE) complex that is long-lived and dissociates into several competitive channels: C4H9O2 11CuH, Cu1(C3H6O)1CH3OH, back to rea...Dimethoxyethane; Copper ions; Association reactions; Collision-induced dissociation; Phase state theory2004
99 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
100 Armentrout, Peter B.Dissociative charge transfer reactions of Ar+, Ne+, and He+ with CF4 from thermal to 50 eVGuided ion-beam techniques are used to measure the cross sections for reaction of CF4 with Ar+, Ne+, and H e + from thermal to 50 eV. Dissociative charge transfer followed by successive loss of F atoms are the major processes observed. Only CFx+ (x = 1,2,3) products are observed in the reactions of ...Ion-molecule reactions; Transfer reactions; Carbon tetrafluoride; Rare gas ions; Exothermic reactions; Endothermic reactions; Plasma systems1990
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