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CreatorTitleDescriptionSubjectDate
301 Miller, Joel StevenThree-dimensional network-structured cyanide-based magnetsIntroduction Magnets based on metal oxides have been important for hundreds of years. Magnetite, Fe3O4, Co-doped (y)-Fe2O3, and CrO2 are important examples. The oxide (O2-) bridge between the magnetic metal ions has filled p orbitals (Figure 1a) that provide the pathway for strong spin coup...Magnetic; Ferrimagnetic; Magnetization2000
302 Miller, Joel Steven; Epstein, Arthur J.Three-dimensional ordering, spin excitations, and dilution effects in the quasi-1-D ferromagnetic (DMeFc)(TCNE)The linear chain S = (1/2) molecular ferromagnet decamethylferrocenium tetracyanoethanide [(DMeFc) (TCNE)] has been studied by frequency-dependent ac susceptibility experiments. (X')(T) and (X") (T) exhibit maxima in the temperature range of 4.8 - 4.9 K, which corresponds to the transition tempe...Temperature; Transition; Magnetic1991
303 Armentrout, Peter B.Threshold behavior of endothermic reactions: C+(2P) + H2 → CH+ + HThe reaction C+(2p) + H2 → CH+ + H (1) and its deuterium analog is a model system in ion-molecule chemistry. It is of interest due to its astrophysical significance, because it is an endothermic process, and because the interaction involves several potential energy surfaces. Experimental work ha...Endothermic reactions; Translational energy; Threshold behavior1984
304 Armentrout, Peter B.Threshold collision-induced dissociation of Sr2+ (H2 O) x complexes (x=1-6): an experimental and theoretical investigation of the complete inner shell hydration energies of Sr2+The sequential bond energies of Sr2+(H2O)x complexes, where x=1-6, are determined by threshold collision-induced dissociation using a guided ion beam tandem mass spectrometer equipped with an electrospray ionization source. The electrospray source produces an initial distribution of Sr2+(H2O)x compl...2010
305 Armentrout, Peter B.Threshold collision-induced dissociation of hydrated cadmium (II): experimental and theoretical investigation of the binding energies for Cd2+(H2O)n complexes (n = 4-11)The first experimentally determined hydration energies of Cd2+(H2O)n complexes, n = 4 - 11, are measured using threshold collision-induced dissociation in a guided-ion-beam tandem mass spectrometer coupled with an electrospray-ionization source. Kinetic-energy-dependent cross-sections are obtained a...Hydrated cadmium; Collision-induced dissociation; Hydration energies; Cadmium complexes2010-02
306 Armentrout, Peter B.Transition metal cluster ion chemistryThe reactivity and thermochemistry of ionic metal atoms and clusters has been explored using guided ion beam mass spectrometry. With this apparatus, cross sections of ion-molecule reactions can be measured from thermal energies to hundreds of eV. Application to metal cluster chemistry demonstrates...Metal clusters; Manganese ions; Endothermic reactions1986
307 Armentrout, Peter B.Translational energy dependence of Ar+ + XY → ArX+ + Y (XY = H2, D2, HD) from thermal to 30 eV c.m.Cross sections for the reactions of Ar+ with H2, D2, and HD to form ArH + and ArD + are measured using a new guided ion beam tandem mass spectrometer which affords an experimental energy range from 0.05 to 500 eV laboratory. The apparatus and experimental techniques are described in detail. Cross se...Translational energy; Ion-molecule reactions; Ion energy; Argon; Hydrogen; Endothermic reactions1985
308 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
309 Poulter, Charles DaleTrisammonium geranyl diphosphateGeranyl chloride. To a flame-dried, 100-mL, three-necked, round-bottomed flask equipped with a magnetic stirrer, low temperature thermometer, rubber septum, and nitrogen inlet adapter, is added 1 .47 g (11 mmol) of N-chlorosuccinimide (Note 1) . The powder is dissolved in 45 mL of dry dichloromet...Buffer; Solution; Chloride1987
310 Miller, Joel StevenTwo-dimensional molecular-based ferrimamagnets incorporating decamethylmetallocenium cationsFour new molecular-based magnets have been synthesized, and their magnetic properties have been investigated in detail. Their formulae are [M'(C5Me5)2]2M2[Cu(opba)]3.(DMSO)x(H20)y with M' = Fe, M = Mn, x = 5, y = 4 (1), M' = Fe, M = Co, x = 6, y = 4 (2), M' = Co, M = Mn, x = 5.5, y = 4 (3) and M' = ...Magnetic; Compounds1996
311 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
312 Morse, Michael DavidUltraviolet photoelectron spectroscopy of molybdenum and molybdenum monoxide anionsThe 351 nm photoelectron spectra of Mo-and MoO- have been measured. The electron affinity of atomic molybdenum is 0.748(2) eV and that of molybdenum monoxide is 1.290(6) eV. The term energies of several MoO electronic states not previously observed are obtained and compared with ab initio prediction...1995
313 Miller, Joel StevenUsing fissionAtoms are just like people, both are lazy. Energy is a measure of work, i.e., more work implies more energy. Atoms do not like to work, hence they try to reduce the energy in their atomic system. For different elements the energy reduction occurs by reaction, e.g., an energetic sodium atom reacts w...Uranium-235; Uranium-2381966
314 Minteer, Shelley D.Utilizing DNA for electrocatalysis: DNA-Nickel aggregates as anodic electrocatalysts for methanol, ethanol, glycerol, and glucoseDNA-nickel aggregates were electrodeposited onto glassy carbon electrode surfaces and have shown electrocatalytic activity for oxidation of methanol, ethanol, glycerol, and glucose at room temperature in alkaline solutions. Bulk electrolysis oxidation products identified by 13C NMR include carbonate...2013-01-01
315 Morse, Michael DavidVibronic spectroscopy of unsaturated transition metal complexes: CrC?H, CrCh?, and NiCH?Vibronically resolved resonant two-photon ionization and dispersed fluorescence spectra of the organometallic radicals CrC2H, CrCH3 , and NiCH3 are reported in the visible and near-infrared wavelength regions. For CrC2H, a complicated vibronic spectrum is found in the 11 100?13 300 cm-1 region, with...2004
316 Miller, Joel Steven; Epstein, Arthur J.Viscous behavior in a quasi-1D fractal cluster glassThe spin glass transition of a quasi-1D organic-based magnet ([MnTPP][TCNE]) is explored using both ac and dc measurements. A scaling analysis of the ac susceptibility shows a spin glass transition near 4 K, with a viscous decay of the thermoremanent magnetization recorded above 4 K.We propose an ex...Transition; Magnet; Magnetization2002
317 Miller, Joel Steven; Epstein, Arthur J.X-ray observation of crossover of 2kF to 4kF scattering in (N-Methylphenazinium)x(Phenazine)1-x(Tetracyanoquinodimethane) [(NMP)x(Phen)1-x(TCNQ)], 0.5 (< _x <_ 1.0)We report the temperature-dependent x-ray diffuse scattering of (NMP),(Phen)(1-x-)(TCNQ) as a function of conduction-electron density (x). With decreasing x three different unique electronic instability regimes are successively observed on the TCNQ chains: (i) the 2kF instability for (2/3<_x<_1, (ii...Conduction-electron; Electron density; Chain1982
318 Poulter, Charles DaleYeast squalene synthase. A mechanism for addition of substrates and activation by NADPHSqualene synthase catalyzes the condensation of two molecules of farnesyl diphosphate (FPP) to give presqualene diphosphate (PSPP) and the subsequent reductive rearrangement of PSPP to squalene. Previous studies of the mechanism of addition of FPP to the enzyme have led to conflicting interpretation...Enzyme Activation; Sesquiterpenes; Kinetics1993-04-15
319 Miller, Joel StevenZero field splitting, field-dependent magnetization of mixed-valent S = 3/2 Diruthenium(II,III) tetracarboxylatesThe 2 K field-dependent magnetization, M(H), of S = 3/2 [RunII/III2(OAc)4]+ was studied. [RuII/III 2(OAc)4]+ exhibits an unusually low magnetization with respect to that predicted by the classical Brillouin function. This reduced value is a consequence of the large anisotropy arising from the large ...Spin; Coupling; Expressions2004
320 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
321 Miller, Joel Steven[Et4N]2[TCNE]2 (TCNE = tetracyanoethylene) - an example of an exceptionally long 2.827 Ã CC bondInterest in organic compounds exhibiting unusually long CC bonds has been the subject of several recent studies.1-3 The longest sp3-sp3 C-C single bond reported to date is 1.73 A°,1,2 whereas several [TCNE]22- (TCNE = tetracyanoethylene) dimers have been recently reported to form cation-assisted, l...Synthesis; Crystal; Solution2001
322 Miller, Joel Steven[MeNC5H5]2[TCNE]2 (TCNE = tetracyanoethylene). Single crystal X-ray and neutron diffraction characterization of an exceptionally long 2.8 Å C-C bondThe reaction of N-methylpyridinium iodide, Mepy+I-, and tetracyanoethylene (TCNE) forms [Mepy]2[TCNE]2, which possesses [TCNE]2 2' with an intradimer C-C bond distance of 2.806(1)Å at 50 K from X-ray diffraction, and 2.801(4)Å at 50 K from neutron diffraction. In the IR it exhibits nChN absorption...C-C bond; Tetracyanoethylene; Neutron diffraction; X-ray diffraction; Multicenter C-C bonding2009
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