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CreatorTitleDescriptionSubjectDate
176 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
177 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled OsN: 520?418 nmThe optical transitions of supersonically cooled OsN have been investigated in the range from 19 200 to 23 900 cm?1 using resonant two-photon ionization spectroscopy. More than 20 vibronic bands were observed, 17 of which were rotationally resolved and analyzed. The ground state is confirmed to be 2...2011
178 Miller, Joel Steven; Epstein, Arthur J.Solitons in nearly commensurate organic charge transfer crystalsX-ray diffuse scattering, magnetic, and conductivity studies of (N-methylphenazinium)x (phenazine)1-x (tetracyanoquinodimethan) [(NMPx(Phen)1-x (TCNQ)] show the formation of defect states for 0.50≤x≤0.54. These results are in agreement with the formation of solitons in a highly correlated quasi-...Charge-transfer salts1983
179 Morse, Michael DavidRotationally resolved spectra of jet-cooled VMoThe Author's report the first gas-phase spectroscopic investigation of diatomic vanadium molybdenum (VMo). The molecules were produced by laser ablation of a VMo alloy disk and cooled in a helium supersonic expansion. The jet-cooled VMo molecules were studied using resonant two-photon ionization sp...2007
180 Morse, Michael DavidElectronic structure of the 4 d transition metal carbides: dispersed fluorsecence spectroscopy of MoC, RuC, and PdCDispersed fluorescence studies of the diatomic molecules MoC, RuC, and PdC are reported. New states identified in MoC and RuC are the [...]2??12??, ?,??? states and the [...]2??12??, ??? state, respectively. Five states are observed by dispersed fluorescence in PdC. The ground state is found to be [...2011
181 Armentrout, Peter B.Guided ion beam studies of the reactions of Nin+ (n=2-18) with O2: nickel cluster oxide and dioxide bond energiesThe kinetic energy dependences of the reactions of Nin + (n=2 - 18) with O2 are studied in a guided ion beam tandem mass spectrometer. A variety of NimO2+, NimO+, and Nim+ product ions, where m<n, are observed, with the dioxide cluster ions dominating the products for all larger reactant cluster io...Metal clusters; Nickel oxide; Nickel dioxide; Bond energies; Collision-induced dissociation; Exothermic reactions2003
182 Wight, Charles AlbertThermal analysis of high explosives: liquid state decomposition of RDXNonisothermal thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) have been applied to the thermal decomposition of RDX. Model-free isoconversional analysis of TGA and DSC traces show that RDX primarily evaporates in an open pan with an activation energy of Eα -100 kJ ...RDX; Plastic explosives; Decomposition; Thermogravimetric analysis; Differential scanning calorimetry2000
183 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
184 Miller, Joel Steven; Epstein, Arthur J.Ferromagnetic behavior of decamethylchromocenium tetracyanoethenide, [CrCp*2][TCNE]Studies on the magnetic properties of decamethylchromocenium tetracyanoethanide, [CrCp*2][TCNE] are reported herein. Near-zero field (H= 150 mG) data indicates a ferromagnetic transition with T(c)=3.65 K. The temperature dependence below T(c) can be fit to a mean-field result M=M(o)(1 - T(o))(1/2)...Magnetic; Magnetization; Transition1993
185 Armentrout, Peter B.Energy dependence, kinetic isotope effects, and thermochemistry of the nearly thermoneutral reactions of N+(3P) + H2(HD, D2) → NH+(ND+) + H(D)The reactions of N + (3P) ions with H2 , HD, D2 are examined using guided ion beam tandem mass spectroscopy. Absolute reaction cross sections are measured from near thermal energies to 30 eV relative energy. The low energy cross section behavior is analyzed using empirical threshold models and ph...Thermoneutral reactions; Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Phase space theory1987
186 Morse, Michael DavidElectron spin resonance investigation of Sc?+ in neon matrices and assignment of its ground electronic state as X ???. comparison with theoretical calculationsThe discandium radical cation, Sc+2 , has been isolated in neon matrices at 4 K and studied by electron spin resonance (ESR) spectroscopy and theoretical methods. It was produced by the x-irradiation of neon matrix samples containing neutral ScZ which was formed by trapping the products generated fr...1993
187 Miller, Joel Steven; Epstein, Arthur J.Magnetization and dynamics of reentrant ferrimagnetic spin-glass [MnTPP]::+[TCNE].-.2PhMeWe present direct current (dc) magnetization M(T,H) and alternating current (ac) susceptibility Xac(T,H,f) data for the quasi-one-dimensional molecule-based ferrimagnet [MnTPP]::+[TCNE].-.•2PhMe (TPP=meso-tetraphenylporphyrinato, TCNE=tetracyanoethylene). Static scaling of the real part X' of ...Ferrimagnetic order; Magnetism1996
188 Miller, Joel Steven; Epstein, Arthur J.Effect of solvent on the magnetic properties of the high-temperature V[TCNE]x molecule-based magnetThe different magnetic behaviors of the V[TCNE]x (TCNE=tetracyanoethylene) magnet prepared via the reaction of TCNE and V(CO)6 in CH2Cl2 and the solvent-free chemical vapor deposition (CVD) of TCNE and V(CO)6 onto a glass substrate were determined. It was shown that the presence of noncoordinating C...Magnetization; Molecule2001
189 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
190 Miller, Joel StevenIsolation of two salts from the reduction of TCNE with [(n-C3H7)4N]I. A further example of long 2.87 Ã pi-C-C bonding in pi-[TCNE]22-Reduction of tetracyanoethylene, TCNE, with tetrakis(n-propyl)ammonium iodide, [Pr4N]I, results in a new example of long pi*-CC bonded pi-[TCNE]22- dimers with a 2.870(4) A(°) intradimer CC bond, which is structurally and spectroscopically characterized. This reaction also results in isolation of ...Synthesis; Intradimer; Crystals2002
191 Miller, Joel StevenCluster glass state and photoinduced effects on the freezing dynamics in KxCo[Fe(CN)6]y.ZH2O (x-0.16,y-0.72, z-4.4)The magnetic properties and photoinduced magnetization of a Prussian blue analog, KxCo[Fe(Cn)6]y•ZH2O (x-0.16, y-0.72, z-4.4) were systematically studied. The frequency dependence of the linear ac susceptibility, the irreversibility in the field-cooled/ zero-field-cooled magnetization (MFC /MZFC)...Hexacyanide; Illumination; Temperatures2000
192 Miller, Joel Steven; Epstein, Arthur J.Ferromagnetism in molecular decamethylferrocenium tetracyanoethylenide: (DMeFc TCNE)The temperature and magnetic field dependence of the magnetization and susceptibility of single-crystal decamethylferrocenium tetracyanoethenide demonstrate that this material is the first molecular compound with a ferromagnetic ground state. A spontaneous magnetization is observed for T < 4.8 K. T...Magnetization; Ferromagnetic1987
193 Miller, Joel StevenOptical properties of cesium tetracyanoquinodimethanide, Cs2(TCNQ)3Room-temperature polarized reflectance measurements have been made on cesium tetracyanoquinodimethanide, Cs2(TCNQI3, over the frequency range between the far infrared and the near ultraviolet. The optical properties of the compound were obtained by Kramers-Kronig analysis. These properties are dom...Electrons; Lattice; Molecules1981
194 Armentrout, Peter B.Reaction of Cr+, Mn+, Fe+, Co+, and Ni+ with O2 and N2O. Examination of the translational energy dependence of the cross sections of endothermic reactionsReactions of Cr+, Mn+, Fe+, Co+, and Ni+ with 02 and N20 to yield metal oxide ions are examined using an ion beam apparatus. Reaction cross sections a as a function of ion translational energy E are reported. With one exception, Fe+ + N20, the cross sections exhibit an energy threshold E0.Metal oxides; Endothermic reactions; Translational energy; Bond energy; Threshold energy1982
195 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
196 Miller, Joel StevenPreparation and characterization of square-planar tetrakis(cyanoacetylide) complexes: [MII(C=C-C=N)4]2- (M = Ni,Pd, Pt)Complexes [MII(C=C-=N)4]2 - (M = Ni, Pd, Pt) are prepared for the first time and the structure of [NEt4]2[Ni(C=C-C=N)4] is determined to have a square-planar geometryBonding; Structure; Ligand1996
197 Armentrout, Peter B.Supporting information for infrared multiple photon dissociation spectroscopy of cationized methionine: effects of alkali-metal cation size on gas-phase conformationA description of the structures of Met and M+(Met) for M+ = Li+, Na+, K+, Rb+, and Cs+. Two figures (S1a and S1b) depicting the 298 K Gibbs free energies calculated at the R/6- 311+G(2d,2p)//B3LYP/6-311+G(d,p) (M+ = Li+, Na+, K+) and R/HW*/6-311+G(2d,2p)// B3LYP/HW*6-311+G(d,p) (M+ = Rb+ and Cs+) le...2010
198 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
199 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
200 Miller, Joel Steven; Epstein, Arthur J.Optical properties of the cation-deficient platinum chain salt K1.75Pt(CN)4¢1.5H2OThe room-temperature polarized reflectance of a potassium-deficient platinum chain salt K1.75Pt(CN)4.1.5Hz[K0 (def)CP] has been measured in the infrared and visible. The reflectance is strongly anisotropic, with a plasma edge in the red and high reflectance in the infrared for light polarized para...Reflectance; Crystals; Lattice1982
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