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CreatorTitleDescriptionSubjectDate
76 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
77 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
78 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
79 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
80 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
81 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
82 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
83 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
84 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
85 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
86 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
87 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
88 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
89 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
90 Miller, Joel Steven; Epstein, Arthur J.Optical control of magnetic order in molecule-based magnet Mn(TCNE)x.y(CH2Cl2)Studies of photoinduced magnetization and photoinduced absorption in molecule-based magnet Mn(TCNE)x•y(CH2Cl2) (x=2, y-0.8, TCNE=tetracyanoethylene) are reported. Optical excitation in the blue region of spectrum leads to increased magnetization, accompanied by changes in the electronic spectrum...Spectrum; Absorption; Illumination2002
91 Morse, Michael DavidLaser vaporization generation of Y ??B+, Y ??B+, and YAI+ for electron spin resonance studies in neon matrices at 4 K: comparison with theoretical calculationsThe first spectroscopic investigation of 89Y 10B+, 89Y 11B+, and 89Y 27Al+ is reported, revealing that both of these diatomic cation radicals have X 4?- electronic ground states. The ions were generated by three high energy techniques in combination with neon matrix isolation at 4 K and studied by e...1992
92 Miller, Joel StevenMnII(TCNE)3/2(I3)1/2-A 3D network-structured organic-based magnet and comparison to a 2-D analogOrganic-based magnets utilize unpaired electrons residing on organic species to form magnetically ordered materials. Unlike traditional atom/ion-based magnets, they enable the controllable modulation and combination of magnetic properties with other technologically important properties (e.g., electr...2010
93 Morse, Michael DavidSpectroscopy and electronic structure of jet-cooled NiPd and PdPtResonant two-photon ionization spectroscopy of jet-cooled NiPd and PdPt has revealed a dense vibronic spectrum for NiPd and a much more sparse spectrum for PdPt. Four vibrational progressions have been identified for NiPd, and three have been located for PdPt. High resolution investigations of NiPd...1990
94 Armentrout, Peter B.Reactions of Ta+ and W+ with H2, D2, and HD: effect of lanthanide contraction and spin-orbit interactions on reactivity and thermochemistryA guided ion beam tandem mass spectrometer is used to examine the kinetic energy dependence of reactions of the third-row transition metal cations, Ta1, and W1, with molecular hydrogen and its isotopologs. A flow tube ion source produces Ta1 and W1 ions in their electronic ground state term and p...Metal clusters; Tantalum ions; Tungsten ions; Lanthanide contraction; Bond energies; Endothermic reactions; Transition metal ions; Dihydrogen2002
95 Armentrout, Peter B.Mechanism of proton exchange: guided ion beam studies of the reactions, H(H2O)n+ (n=1-4) + D2O and D(D 2O)n+ (n=1-4) + H2OReactions of protonated water clusters, H(H2O)n+ (n=1-4) with D2O and their "mirror" reactions, D(D2O)n+ (n=1-4) with H2O, are are studied using guided-ion beam mass spectrometry. Absolute reaction cross sections are determined as a function of collision energy from thermal energy to over 10 eV.Collision-induced dissociation; Proton exchange; Protonated water clusters; Exothermic reactions; Deuterium oxide2004
96 Morse, Michael DavidSpectroscopy of mixed early-late transition metal diatomics: ScNi, YPd, and ZrCoResonant two-photon ionization spectroscopy has been employed to investigate the spectra of the jet-cooled transition metal diatomics ScNi, YPd, and ZrCo, which are isovalent species which possess ~or are thought to possess! an X 2?+ ground state. Several electronic band systems have been observed f...1994
97 Miller, Joel Steven[Cyanil]2 2- dimers possess long, two-electron ten-center (2e-/10c) multicenter bondingA long, two-electron ten-center (2e-/10c) [8 carbon plus 2 oxygen] bond in diamagnetic dimers of radical-anion tetracyano-1,4-benzoquinoneide (cyanil, [Q]2 2-, is described by B2LYP and CASSCF92,2)/MCQDPT calculations.Carbon bonds; Cyanil2008
98 Morse, Michael DavidSpectrsocopy of Jet-cooled YCuOptical spectra of jet-cooled diatomic YCu have been recorded using resonant two-photon ionization spectroscopy in a supersonic expansion of helium. The ground state is shown experimentally to be of 1?+ symmetry, with a measured bond length of re"=2.6197(6) ? and a vibrational frequency of 193.21(24...1995
99 Miller, Joel Steven; Epstein, Arthur J.Optical properties of quinolinium tetracyanoquinodimethanide, [Qn(TCNQ)2] and (N-methylphenazinium)x(phenazine)1-x (tetracyanoquinodimethane) [(NMP)x(Phen)1-x(TCNQ)]We present here optical-absorption data of quinolinium ditetracyanoquinodimethanide [Qn(TCNQ)2] and (N-methylphenazinium)x(phenazine)1-x(tetracyanoquinodimethanide) [(NMP)x(Phen)1-x(TCNQ)] for 0.5 <_x<_ 0.6. These materials span the range of electronic structure from commensurate, to commensurate ...Commensurate; Lattice; Electron1989
100 Morse, Michael DavidLaser excitation spectroscopy of the A and B states of jet-cooled copper dimer: evidence for large electronic isotope shiftsFluorescence excitation spectra recorded for the A-X system of jet-cooled Cu2 show conclusive evidence of a ?? = 0 transition, and the A state is thereby definitively assigned as ??u+. A previous assignment of the B state as ??u+ is confirmed, but the vibrational levels of this state are complicated...1989
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