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CreatorTitleDescriptionSubjectDate
251 Miller, Joel StevenStructure, optical and magnetic behaviour of meso-tetraphenyl-porphyrinatoiron(III) tetracyanoethenide, [FeIII(TPP)]+[TCNE].-*The direct redox reaction between tetracyanoethylene (TCNE) and meso-tetraphenylporphyrinatoiron(II), [FeII(TPP)], formed the electron transfer salt (ETS) [FeIII(TPP)][TCNE], which has been structurally, spectroscopically, and magnetically characterized. It has an extended one-dimensional linear ch...Magnets; Spin; Electron2001
252 Morse, Michael DavidNi? revisited: reassignment of the ground electronic stateResonant two-photon ionization spectroscopy was used to study jet-cooled Ni2 produced by pulsed laser ablation of a nickel target in the throat of a supersonic nozzle using argon as the carrier gas. Spectral regions previously investigated using helium as the carrier gas were reinvestigated, and the...1994
253 Armentrout, Peter B.Spin-orbit state-selected reactions of Xe+(2P3/2 and 2P1/2) with H2, D2, and HDSpin-orbit state-selected reactions of X e + (2Pj ), j = 3/2 and 1/2, with isotopic molecular hydrogen (H2 , D2 , and HD) to form X e H + and XeD + are studied using guided ion beam mass spectrometry. Reaction cross sections are determined as a function of reactant kinetic energy from near thermal ...Spin-orbit; Xenon ions; Hydrogen isotopes; Isotope effects; Ion-molecule reactions1989
254 Miller, Joel StevenMagnetization and static scaling of high-Tc disordered molecular-based magnet V(tetracyanoethylene)x¢y(CH3CN) with x ~ 1.5 and y ~ 2)We report field (H) and temperature (T) -dependent magnetization (M) of a member of the new class of high-Tc molecular-based magnets V(tetracyanoethylene)x .y(solvent) with Tc in an accessible range (solvent =CH3CN). The M (H) at low T saturates slowly with increasing H. The random magnetic anisotro...Temperature; Magnetic; Random1993
255 Armentrout, Peter B.C+(2P) + H2(D2,HD)→CH+(CD+) + H(D). I. Reaction cross sections and kinetic isotope effects from threshold to 15 eV c.m.Total cross sections for the reactions of carbon (1 + ) ions with isotopic molecular hydrogen (H2, D2 , and HD) to form methyliumylidene (CH+ and C D + ) have been measured using guided ion beam techniques. Cross sections are reported as a function of the translational energy of the reactants fro...Ion-molecule reactions; Isotope effects; Translational energy; Threshold behavior; Endothermic reactions1986
256 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
257 Miller, Joel StevenInnovation in crystal engineeringThe first CrystEngComm discussion meeting on crystal engineering has demonstrated that the field has reached maturity in some areas (for example: design strategies, characterization of solid compounds, topological analysis of weak and strong non-covalent interactions), while the quest for novel pro...Research; Design; Molecular2002
258 Morse, Michael DavidOptical spectroscopy of jet-cooled FeC between 12 000 and 18 100 cm-?Iron monocarbide has been investigated between 12 000 and 18 100 cm21 in a supersonic expansion by resonant two-photon ionization spectroscopy. Six new electronic states have been identified for which origins relative to the ground state have been determined. Three of these possess ?"=3, one possess...1997
259 Armentrout, Peter B.Kinetic-energy dependence of competitive spin-allowed and spin-forbidden reactions: V++CS2The kinetic-energy dependence of the V++CS2 reaction is examined using guided ion-beam mass spectrometry. Several different ion sources are used to systematically vary the V+ electronic state distributions and elucidate the reactivities of both the ground and excited state V+ cation.Carbon disulfide; Vanadium ions; Transition metal ions; Bond energies; Endothermic reactions; Exothermic reactions1999
260 Armentrout, Peter B.IR spectroscopy of cationized aliphatic amino acids: stability of charge-solvated structure increases with metal cation sizeAbstract Gas-phase structures of alkali metal cationized (Li+, Na+, K+, Rb+, Cs+) proline (Pro) and N-methyl alanine have been investigated using infrared multiple photon dissociation (IRMPD) spectroscopy utilizing light generated by a free electron laser and computational modeling. Measured IRMPD...2010-11
261 Armentrout, Peter B.Spin-orbit state-selected reactions of Kr+(2P3/2 and 2P1/2) with H2, D2, and HD from thermal energies to 20 eV c.m.Spin-orbit state-selected reactions of K r + (2Pj), J = 3/2 and / = 1/2, with isotopic molecular hydrogen (H2 , D2 , and HD) to form KrH+ and Kr D+ are investigated using guided ion beam techniques. Reaction cross sections for each spin-orbit state are measured as a function of the relative trans...Spin-orbit; Krypton ions; Hydrogen isotopes; Isotope effects; Potential energy surfaces; Ion-molecule reactions1986
262 Miller, Joel Steven; Epstein, Arthur J.Direct evidence of electron spin polarization from an organic-based magnet: [FeII(TCNE)(NCMe)2][FeIII Cl4]Direct evidence of an organic-based magnet with a finite electron spin polarization at the Fermi edge is shown from spin-resolved photoemission of the [FeII(TCNE)(NCMe)2][FeIIICl4] organic-based magnet. The 23% majority-based spin polarization at the Fermi edge is observed at 80 K in zero applied fi...Organic-based magnets; Electron spin polarization2009-05
263 Stang, Peter J.Incorporation of flexible pyridine-functionalized ligands into discrete supramolecules via coordination-driven self-assemblyFlexible, pyridine-functionalized ligands were self-assembled into discrete supramolecules of differing stoichiometries upon combination with various organoplatinum molecules. They are characterized by electrospray ionization mass spectrometry, 31P(iHI and 'H NMR. Despite its inherent flexibility, 3...Self-assembly; Coordination-driven; Transition-metal-mediated; Flexible ligands; Pyridyl ligands; Supramolecules2004
264 Truong, ThanhDirect ab initio dynamics studies of the hydrogen abstraction reactions of hydrogen atom with fluoromethanesA direct ab initio dynamics study on the gas-phase reactions of atomic hydrogen with different fluoromethanes has been carried out. The thermal rate constants were calculated using canonical variational transition state (CVT) theory augmented by multidimensional semiclassical zero and small curvatur...Hydrogen abstraction reactions; Gas-phase reactions; Fluoromethanes; Thermal rate constants; Moller?Plesset perturbation theory; Hybrid density functional theory1999
265 Voth, Gregory AlanAb initio calculations of reactive pathways for ?-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (?-HMX)Using the BLYP and B3LYP level of density functional theory, four possible decomposition reaction pathways of HMX in the gas phase were investigated: N?NO2 bond dissociation, HONO elimination, C?N bond scission of the ring, and the concerted ring fission. The energetics of each of these four mechan...Ab initio calculations; Reactive pathways; HMX2000
266 Wight, Charles AlbertEstimating realistic confidence intervals for the activation energy determined from thermoanalytical measurementsA statistical procedure is proposed for estimating realistic confidence intervals for the activation energy determined by using an advanced isoconversional method. Nine sets of five thermogravimetric measurements have been produced for the process of gassification of ammonium nitrate at five differe...Thermoanalysis; Activation energy; Isoconversional method2000
267 Orendt, Anita; Pugmire, Ronald J.Carbon-13 chemical shift tensors in polycyclic aromiatic compounds. 9. BiphenyleneThe principal values of the 13C chemical-shift tensors of natural abundance biphenylene were measured at room temperature with the FIREMAT experiment. Of 18 crystallographically distinct positions (three sets of six congruent carbons each), the three primary bands have been resolved into seven singl...Carbon-13; Chemical-shift tensors; Biphenylene; Polycyclic aromiatic compounds; FIREMAT2000
268 Truong, ThanhImportance of polarization in simulations of condensed phased energetic materialsAn embedded cluster model is used to estimate the molecular dipole moment of crystalline dimethylnitramine (DMNA). The electrostatic potential due to the crystal is included in the calculation via the SCREEP (surface charge representation of the electrostatic embedding potential) approach. The resul...Dimethylnitramine; DMNA; Embedded cluster model1999
269 Truong, ThanhBranching ratio and pressure dependent rate constants of multichannel unimolecular decomposition of gas-phase ?-HMX: an ab initio dynamics studyThe dynamics of the initial thermal decomposition step of gas-phase ?-HMX is investigated using the master equation method. Both the NO2 fission and HONO elimination channels were considered. The structures, energies, and Hessian information along the minimum energy paths (MEP) of these two channels...Thermal decomposition; HMX2001
270 Voth, Gregory AlanSystematic coarse-graining of nanoparticle interactions in molecular dynamics simulationA recently developed multiscale coarse-graining procedure [Izvekov, S.; Voth, G. A. J. Phys. Chem. B 2005, 109, 2469] is extended to derive coarse-grained models for nanoparticles. The methodology is applied to C60 and to carbonaceous nanoparticles produced in combustion environments. The coarse-gra...Systematic coarse-graining; Multiscale coarse-graining2005
271 Wight, Charles AlbertCompetitive vaporization and decomposition of liquid RDXThe thermal decomposition of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) has been studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Activation energies as a function of the extent of conversion, ?, have been determined by model-free isoconversional analysis o...Liquid RDX; Competitive vaporization; Thermal decomposition; Differential scanning calorimetry2000
272 Wight, Charles AlbertThermal activation of the high explosive NTO: sublimation, decomposition, and autocatalysisThermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) show that the heating of 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one (NTO) leads to competitive sublimation and condensed-phase exothermic decomposition. Model-free isoconversional analysis has determined activation energies...NTO; Thermal activation; Differential scanning calorimetry; Exothermic decomposition; Competitive sublimation2002
273 Truong, ThanhThermal rate constants of the NO2 fission reaction of gas phase ?-HMX: a direct ab initio dynamics studyThe NO2 fission reaction of gas phase ?-HMX has been studied using a direct ab initio method within the framework of microcanonical variational transition state theory (?VT). The potential energy calculations were calculated using the hybrid nonlocal B3LYP density functional theory with the cc-pVDZ ...HMX; Fission reaction; Thermal rate constants; Microcanonical variational transition state theory2000
274 Voth, Gregory AlanElectronic structure calculation of the structures and energies of the three pure polymorphic forms of crystalline HMXThe molecular structures and energetic stabilities of the three pure polymorphic forms of crystalline HMX were calculated using a first-principles electronic-structure method. The computations were performed using the local density approximation in conjunction with localized "fireball" orbitals and ...HMX; Crystalline HMX; Molecular geometry2000
275 Wight, Charles AlbertKinetic study of stabilizing effect of oxygen on thermal degradation of poly(methyl methacrylate)The thermal degradation of poly(methyl methacrylate) (PMMA) has been studied in both pure nitrogen and oxygen-containing atmospheres. The presence of oxygen increases the initial decomposition temperature by 70 °C. The stabilizing effect of oxygen may be explained by forming thermally stable radica...Poly(methyl methacrylate); PMMA; Thermal degradation; Isoconversional method1999
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