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1 Miller, Joel StevenStructure of CrIIF(NCMe)2BF4. Rietveld refinement of a component of a physical mixture of unknown compositionThe reaction of CrII(NCMe)4(BF4)2 and [NBun 4][TCNE] (TCNE ¼ tetracyanoethylene) in CH2Cl2 forms a solid that is a mixture of an amorphous reduced-TCNE containing phase(s) and a crystalline component. Rietveld refinement of the high-resolution, synchrotron X-ray powder pattern enabled the determi...Organic-based magnets; Powder X-ray diffraction; Tetracyanoethylene2008
2 Morse, Michael DavidSpectroscopy and electronic structure of jet-cooled GaAsAn optical spectrum, obtained by resonant two-photon ionization spectroscopy, is reported for jet-cooled diatomic gallium arsenide. The ground state is identified as X??-, deriving from a ??rr? molecular configuration, and is characterized by ?" = 215 cm-1, ?"exe" = 3 cm-1, and r0' = 2.53 ? 0.02 ?. ...1989
3 Miller, Joel Steven; Epstein, Arthur J.Quest for a polymeric ferromagnet: a new polymorph of 1,4-bis(2,2,6,6-tetramethyl-4-oxy-4-piperidyl-1-oxy)butadiyne (invited)A new polymorph of 1,4-bis(2,2,6,6-tetramethyl-4-oxy-4-piperidyl-l-oxy) butadiyne has been prepared and characterized by x-ray diffraction, infrared and Raman spectroscopies, and magnetic susceptibility. Unlike t h e Pccn-a phase, the B phase belongs to the Pca2y1 space group [a = 14.265(1) A(o),b ...Molecular; Magnetic; Thermal1988
4 Morse, Michael DavidDispersed fluorsecence spectroscopy of jet-cooled AgAu and Pt?Dispersed fluorescence spectroscopy has been used to study jet-cooled AgAu and Pt2 . Fluorescence resulting from the excitation of five bands of the A?X 1?+ system of AgAu was dispersed, and 51 measured ground state vibrational levels were fit to provide ground state vibrational constants of ?"e=198...2001
5 Armentrout, Peter B.Statistical modeling of sequential collision-induced dissociation thresholdsThermochemistry determined from careful analysis of the energy dependence of cross sections for collision-induced dissociation (CID) reactions has primarily come from the primary dissociation channel. Higher order dissociations generally have thresholds measured to be higher than the thermodynamic ...Collision-induced dissociation; Endothermic reactions2007
6 Truong, ThanhReaction class transition state theory: hydrogen abstraction reactions by hydrogen atoms as test casesWe present a new method called Reaction Class Transition State Theory (RC-TST) for estimating thermal rate constants of a large number of reactions in a class. This method is based on the transition state theory framework within the reaction class approach. Thermal rate constants of a given reacti...Transition state theory; Hydrogen2000
7 Miller, Joel Steven; Liao, YiSynthesis and structure of an asymmetric copper(I) dimer with two-coordinate and four-coordinate copper(I) sitesCopper(I) coordination compounds have been studied intensively due to their biological relevance, catalytic properties, and theoretical interests. Numerous mononuclear and polynuclear copper(I) complexes with different coordination numbers have been prepared and characterized. Recently the possible ...Polynuclear; Nitrogens; Electrons2000
8 Poulter, Charles DalePredicting the functions and specificity of triterpenoid synthases: a mechanism-based multi-intermediate docking approachTerpenoid synthases construct the carbon skeletons of tens of thousands of natural products. To predict functions and specificity of triterpenoid synthases, a mechanism-based, multi-intermediate docking approach is proposed. In addition to enzyme function prediction, other potential applications of ...2014-01-01
9 Miller, Joel StevenMagnetic behaviors of the metamagnetic and ferromagnetic phases of [Fe(C5Me5)2][TCNQ] (TCNQ = 7,7,8,8-tetracyano-p-quinodimethane). Determination of the phase diagram for the metamagnetic phaseThe detailed magnetic behaviors of the ferro- (1FO) and metamagnetic (1MM) phases of [FeCp*2][TCNE] (Cp* = pentamethylcyclopentadienide; TCNE = tetracyanoethylene) aligned parallel to the applied magnetic field, H, were obtained using eicosane (E). The Tc for 1FO is 3.1 K from the maximum in the fr...Properties; Temperature; Ordering2006
10 Miller, Joel Steven; Epstein, Arthur J.Tetracyanoethylene-based organic magnetsSeveral classes of organic magnets based upon the tetracyanoethenide radical anion, [TCNE](.-), either unbound, (u), and (u4) bonded to zero, two and four metal sites have been reported. The putative (u4) bonded V(TCNE)x room temperature magnet has been extended to include M(TCNE)x(M = Mn, Fe, Co,...Magnetization; Magnetic ordering; Oxidation1998
11 Armentrout, Peter B.Fifty years of ion and neutral thermochemistry by mass spectrometryOriginating with the appearance potentials for "positive rays", the ability of mass spectrometry to obtain quantitative information about the energetics of both ions and neutrals has evolved dramatically. About 50 years ago, many of the techniques that are now common place were first implemented, th...2014-01-01
12 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
13 Stang, Peter J.Studies in the cycloproparene series: cycloaddition reactions of diarylmethylidenecycloproparenesDiarylmethylidenecyclopropanaphthalenes 4b-d add diphenylisobenzofuran (DPIBF) and α-pyrone across the exocyclic double bond to give ring expanded products 11b-d and 13b-d that result from subsequent relief of ring strain in the non-isolable spirocyclic intermediates 10 and 12, respectively. The be...Cycloproparene series; Cycloaddition; Diarylmethylidenecycloproparenes; Ab initio calculations; Strained aromatics; Acetylenic-iodonium salts; Crystal structures; Cyclobutanes, Diels-Alder cycloaddition; norcaradienes2001
14 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
15 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
16 Miller, Joel StevenSynthesis of layered (2-D) V-based bimetallic oxalates from non-aqueous media that cannot be synthesized from aqueous mediaThe reaction of (NBu4)3[VIII(ox)3] (1, ox = oxalate) and M(II) (M= Fe, Co, Ni, Cu) ions in MeCN, leads to the isolation of V-based coordination polymers of [N(n-Bu)4][FeIIVIII(ox)3]? 0.30{[N(n-Bu)4](BF4)} (2), [N(n-Bu)4][CoIIVIII(ox)3]?0.75{[N(n-Bu)4](BF4)} (3), [N(n-Bu)4][NiIIVIII(ox)3]?0.20{[N(n...Magnetic; Coupling; Diffraction2006
17 Armentrout, Peter B.Hydrogen atom transfer reactions of He+ and Ne+ with H2, D2, and HDThe hydrogen atom transfer reactions of helium (1 +) and neon(1+) ions with isotopic molecular hydrogen (H2 , D2 , and HD) are investigated using guided ion beam techniques. These reactions are exothermic, but are known to be extremely slow at thermal energies. The cross sections for formation of...Transfer reactions; Ion-molecule reactions; Exothermic reactions; Hydrogen; Helium ions; Neon ions; Threshold behavior; Isotope effects1987
18 Miller, Joel Steven; Epstein, Arthur J.Linear chain ferromagnetic charge transfer compoundsCharge transfer complexes possessing a ... DADA ... structure with both the donor, D, and acceptor, A, being S = 1/2 radicals may exhibit cooperative magnetic phenomena. The complex [Fe(C5Me5)2]+ [TCNQ]-. exhibits metamagnetic behavior. The similarly structured [TCNE]-. and [C4(CN)6]-. complexes ar...Spin; Exchange; Molecular1986
19 Armentrout, Peter B.Oxidation reactions at variably sized transition metal centers: Fen+ and Nbn+ + O2 (N=1-3)Cross sections for the reactions of Fen+ and Nbn+ (n = 1-3) with 02 are measured as a function of kinetic energy over a range of 0 to > 10 eV. In all systems, analysis yields insight into the kinetics and thermochemistry of the oxidation processes. Nbn+ reaction with 02 exothermically near the Lange...Metal clusters; Nobium ions; Iron ions; Exothermic reactions1989
20 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
21 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
22 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
23 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
24 Armentrout, Peter B.Thermodynamics and mechanisms of protonated diglycine decomposition: a guided ion beam studyWe present a full molecular description of fragmentation reactions of protonated diglycine (H+GG) by studying their collision-induced dissociation (CID) with Xe using a guided ion beam tandem mass spectrometer (GIBMS). Analysis of the kinetic energy-dependent CID cross sections provides the 0 K barr...2012-01-01
25 Armentrout, Peter B.Cobalt carbene ion: reactions of Co+ with C2H4, cyclo-C3H6 and cyclo-C2H4OAn ion beam apparatus is employed to study the formation of the cobalt carbene ion, CoCH2+. This ion is produced in the endothermic reaction of cobalt ions with ethene and cyclopropane and in an exothermic reaction with ethylene oxide. A model is proposed to account for the dependence of experimenta...Cobalt carbine; Ion beam; Bond dissociation energy; Reaction cross section; Endothermic reactions1981
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