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CreatorTitleDescriptionSubjectDate
201 Armentrout, Peter B.; Morse, Michael DavidRydberg and pulsed field ionization-zero electron kinetic energy spectra of YOA spectroscopic study of the Rydberg states of YO accessed from particular rotational levels of the A²Π½, v=0 state has been combined with a pulsed field ionization, zero electron kinetic energy (PFI-ZEKE) investigation. The results provide accurate values of the ionization energy of YO, ionizati...Ionization energy; Rydberg spectra; Yttrium monoxide1999
202 Miller, Joel StevenMnII(N3)2(pyrazine).A 2-D layered structure consisting of ferromagnetically coupled 1-D {Mn(U-1,1-N3)2}n chainsMn(N3)2(pyz) (pyz = pyrazine) consists of ferromagnetically coupled linear chains of {Mn(N3)2}n comprised of u-1,1-azido bridges together with u-pyz ligands to afford 2-D planar layers.Ferromagnetic; Coupling; Magnetic1999
203 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
204 Miller, Joel Steven; Epstein, Arthur J.Magnetic bistability and nucleation of magnetic bubbles in a layered 2D organic-based magnet [Fe(TCNE)(NCMe)2][FeC14]The 2D layered organic-based magnet [Fe(TCNE)(NCMe)2][FeCl4] (TCNE ¼ tetracyanoethylene) exhibits a unique macroscopic magnetic bistability between the field-cooled and zero-field-cooled states, which cannot be explained by either superparamagnetic behavior or spin freezing due to spin glass orde...Organic-based magnets; Tetracyanoethylene; Magnetic bistability; Nucleation2008-11
205 Miller, Joel Steven; Epstein, Arthur J.Ferromagnetic behavior and magnetic excitations in a molecular-based alternating-spin chain: decamethylchromocenium tetracyanoethenideWe report the study of magnetic properties of a molecular-based alternating-spin chain: metallocenium electron-transfer salt decamethylchromocenium tetracyanoethanide, [CrCp(*2)] [TCNE]. We give a modified spin-wave theory for the Heisenberg alternating-spin chains. The low-field susceptibility and...TCNE; Magnetization1994
206 Truong, ThanhCombined reaction class approach with integrated molecular orbital + molecular orbital (IMOMO) methodology: a practical tool for kinetic modelingWe present a new practical computational methodology for predicting thermal rate constants of reactions involving large molecules or a large number of elementary reactions in the same class. This methodology combines the integrated molecular orbital1molecular orbital (IMOMO) approach with our rece...IMOMO; Kinetic modeling; Thermal rate constants2000
207 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
208 Voth, Gregory AlanThe multiscale coarse-graining method. VI. Implementation of three-body coarse-grained potentialsMany methodologies have been proposed to build reliable and computationally fast coarse-grained potentials. Typically, these force fields rely on the assumption that the relevant properties of the system under examination can be reproduced using a pairwise decomposition of the effective coarse-grai...2010
209 Miller, Joel Steven; Epstein, Arthur J.Magnetic phase diagram of a molecule-based ferrimagnet: weak ferromagnetism and multiple dimensionality crossoversA detailed study of the magnetic behavior of the molecule-based magnet, [MnOEP][HCBD], (OEP=mesooctaethylporphyrinato, HCBD=hexacyanobutadiene) from 1.7 to 20 K was performed. The earlier reported magnetic transition at 19.6 K, ascribed to a crossover from a one-dimensional Heisenberg-like ferrimag...Transition; Temperature; Magnetization1997
210 Morse, Michael DavidThe 3d?Ni(?F)3d10Cu???*? manifold of excited electronic states of NiCuDiatomic NiCu has been supersonically cooled in a molecular beam and investigated by resonant two-photon ionization spectroscopy. A total of nine band systems connecting the ground 3d?Ni3??Cu??, X 2?5/2 state to the 3d?Ni(3F)3d??Cu??*?? manifold of states have been found, and bands of eight of these...1992
211 Morse, Michael DavidA pair potentials study of matrix-isolated atomic zinc. II. Intersystem crossing in rare-gas clusters and matricesThe mechanism of 4p 1P1?4p 3PJ intersystem crossing (ISC) following excitation of the 4p 1P1 level of matrix-isolated atomic zinc is investigated using a pair potentials approach. This is achieved by extending earlier ISC calculations on the Zn?RG2 and Zn?RG3 complexes to the square planar Zn?RG4 ...1998
212 Armentrout, Peter B.Kinetic energy dependence of association reactions. A new thermokinetic method for large systemsThe reactions of bare alkali metal ions (M+5Li+, Na+, or K+) with dimethoxyethane (CH3OCH2CH2OCH3 , (DXE) are studied using guided ion beam tandem mass spectrometry. The bimolecular reaction forms an associative M1(DXE) complex that is long-lived and dissociates back to the reactants. The kinetic en...Collision-induced dissociation; Association reactions; Bond energies; Dimethoxyethane; Alkali metal ions2003
213 Morse, Michael DavidLigand-field theory applied to diatomic transition metals. Results for the d?Ad?B?? states of Ni?, the d?Nid??cu?? states of NiCu, and the d?Ni(?F)d??cu???*? excited states of NiCuA ligand-field theory has been developed for transition-metal diatomics having electronic configurations of d?Ad??B??, d?Ad?B?? and d?A(?F)d??B???*?. The theory treats each atom as a point charge and includes spin-orbit interactions. No contributions due to d-orbital chemical bonding are included. ...1992
214 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
215 Miller, Joel StevenPhotoemission of ferrocene, decamethylferrocene, and decamethylferrocene-bis(7,7,8,8-tetracyano-p-quinodimethane)We present the first vacuum ultraviolet photoemission measurements of condensed ferrocene, decamethylferrocene, and the highly conductive charge transfer complex decamethylferrocene-7,7,8,8-tetracyano-p-quinodimethane, at photon energies from 7.7 to 21.2 eV. We compare the electronic spectra of thes...Energy; Transfer; TCNQ1977
216 Armentrout, Peter B.Thermochemistry of small cationic iron-sulfur clustersThe kinetic energy dependences of the reactions of Fen 1 with COS (n=2-6) and CS2 (n=2-5) are studied in a guided-ion beam tandem mass-spectrometer. The main products arise from sulfur transfer and subsequent losses of Fe atoms. In the case of CS2 , this reactant also formally replaces one Fe atom ...Iron-sulfur clusters; Endothermic reactions; Bond energy2002
217 Armentrout, Peter B.Guided ion beam studies of the reactions of Crn + (n=2-18) with O2: chromium cluster oxide and dioxide bond energiesThe kinetic energy dependence of the reactions of Crn+ (n=2-18) with O2 are studied in a guided ion beam mass spectrometer. A variety of CrmO2+, CrmO+, and Crm+ product ions, where m≤n, are observed, with the dioxide cluster ions dominating the products for all larger reactant cluster ions. React...Metal clusters; Chromium ions; Oxygen; Oxygen; Bond energies; Exothermic reactions1998
218 Morse, Michael DavidSpectroscopic studies of jet-cooled AgAu and Au?Resonant two-photon ionization spectroscopy has been applied to the jet-cooled Au? and AgAu molecules. Three new band systems of Au? and two new systems of the poorly characterized AgAu molecule have been observed. Excited state lifetime measurements have been made, and assignments of the excited s...1991
219 Morse, Michael DavidThe bond energy of Rh?In a spectroscopic investigation of jet-cooled Rh2 by the resonant two-photon ionization method, an abrupt predissociation threshold is observed in a dense set of vibronic levels at 19 405?4 cm-1. Based on the high density of states expected in the rhodium dimer, the sharp definition of the prediss...1997
220 Miller, Joel StevenIsolation and structural determination of octacyanobutanediide, [C4(CN)8]2-; precursors to M(TCNE)x magnets(**)The reaction of MI2.xMe3CN (M = Mn, Fe) and TCNE (tetracyanoethylene) leads to unprecedented [C4(CN)8]2-U4-metal complexes which have been crystallographically characterized and are precursors to M(TCNE)x-yS magnets.Absorptions; Magnets; Bond1998
221 Voth, Gregory Alan; Sarofim, Adel F.Identification of pathways for polyaromatic growth using molecular dynamicsReaction pathways for polyaromatic growth in combustion environments are explored theoretically using molecular dynamic techniques. The reaction systems considered include cyclization reactions that involve H atom migration. Specifically we examine the absorption of acetylene on an aromatic ring rad...2004
222 Miller, Joel StevenStructure and physical properties of hexacyanomanganate(IV), [MnIV(CN)6]2-Hydrolytically unstable d3 [MnI V(CN)6]2- as the [N(PPh3)2]+ salt is crystallographically, spectroscopically, and magnetically characterized.Absorption; Magnetic; Spin1997
223 Miller, Joel Steven; Epstein, Arthur J.Decamethylchromocenium tetracyanoethenide, + [Cr(C5Me5)2]:.+[TCNE].-: a molecular ferromagnet with Tc=3.65 KThe electron-transfer salt 4[Cr(C5Me5)2] + [TCNE].-(TCNE = tetracyanoethylene) has been prepared and structurally characterized by single-crystal X-ray diffraction. It possesses a solid-state motif of parallel 1D chains of alternating radical cations and anions similar to, but not isostructural to, ...Magnetic; Electron transfer; Coupling1993
224 Miller, Joel Steven; Epstein, Arthur J.Molecular magnets V(tetracyanoethylene)x.y(solvent): applications to magnetic shieldingThe specific advantages and limitations of a new class of polymer based magnets [exemplified by V(TCNE)x. y (solvent) (TCNE= tetracyanoethylene)] for static and low frequency magnetic shielding and inductive applications are evaluated using results of dc superconducting quantum interference device ...Frequency; Permeability; Transition1994
225 Poulter, Charles DaleLethal mutations in the isoprenoid pathway of salmonella entericaEssential isoprenoid compounds are synthesized using the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway in many gram-negative bacteria, some gram-positive bacteria, some apicomplexan parasites, and plant chloroplasts. The alternative mevalonate pathway is found in archaea and eukaryotes, includin...Isoprenoids; Mutation; Bacteria; Antimicrobials2006
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