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51 Morse, Michael David???X??+ band systems of jet-cooled ScCo and YCoRotationally resolved resonant two-photon ionization (R2PI) spectra of ScCo and YCo are reported. The measured spectra reveal that these molecules possess ground electronic states of 1?+ symmetry, as previously found in the isoelectronic Cr2 and CrMo molecules. The ground state rotational constant...2010
52 Miller, Joel Steven; Epstein, Arthur J.Forthcoming attractionsMagnets made from molecules and ions having spins in p orbitals have only been discovered in the past decade. Their solubility in organic solvents and room temperature manufacture means that they should find a variety of applications.Electron; Temperature; Magnets1994
53 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
54 Morse, Michael DavidSpectroscopic studies of jet-cooled CuAgResonant two-photon ionization spectroscopy has been applied to jet-cooled diatomic CuAg. Four band systems have been observed, three of which have been rotationally resolved and analyzed. The ground state is X ??+ in symmetry, deriving from the 3d??cu4d??Ag?? molecular configuration. Its bond lengt...1991
55 Miller, Joel StevenMagnetically ordered molecule-based assembliesThe development of molecules and assemblies of molecules exhibiting technologically important bulk properties, such as magnetic ordering, is an important worldwide research focus. Organic- and molecule-based magnets have been discovered and several families have been reported with magnetic orderin...Organic-based; Lattices; Magnets2006
56 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled Au?A band system of jet-cooled Au, has been located in the near infrared region of the spectrum using resonant two-photon ionization spectroscopy. The origin band is located at 13 354.15 cm-? and the system extends more than 700 cm-? further to the blue. The excited state displays a radiative lifetime...1991
57 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
58 Armentrout, Peter B.Reactions of Pt+ with H2, D2, and HD: effect of lanthanide contraction on reactivity and thermochemistryA guided ion beam tandem mass spectrometer is used to examine the kinetic energy dependence of reactions of the third-row transition metal cation, Pt1, with molecular hydrogen and its isotopologs. A flow tube ion source produces Pt1 ions in its electronic ground state term and primarily in the lowes...Metal clusters; Platinum ions; Lanthanide contraction; Bond energies; Endothermic reactions; Transition metal ions; Dihydrogen2002
59 Armentrout, Peter B.Activation of methane by size-elected iron cluster cations, Fen+ (n=2-15): cluster-CHx (x=0-3) bond energies and reaction mechanismsThe kinetic energy dependences of the reactions of Fen + (n=2 - 15) with CD4 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-10 eV. All reactions exhibit thresholds and two main products, FenD+ and FenCD2+, are formed.Metal clusters; Iron ions; Bond energies; Dehydrogenation; Endothermic reactions; Transition metal ions2001
60 Morse, Michael DavidSpin-forbidden c??+??X??+ band system of YFOptical spectra of jet-cooled diatomic YF have been recorded using resonant two-photon ionization spectroscopy. A vibrational progression corresponding to the c 3?1+?X 1?+ system has been identified. The vibrational frequency ?e' and anharmonicity ?'exe' of the c 3?+ state are 546.70 and 2.45 cm?1,...2007
61 Miller, Joel StevenEffect of thermal annealing on the ferrimagnetic behavior and ordering of the [MnTXPP]+[TCNE].-.solv (X=F, Cl, Br, I; solv = PhMe, CH2Cl2) family of magnets+5,10,15,20-Tetrakis(4-fluorophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTFPP][TCNE], 1F, 5,10,15,20-tetrakis(4-bromophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTBrPP][TCNE], 1Br, and 5,10,15,20-tetrakis(4-iodophenyl)porphyrinatomanganese(III) tetracyanoethenide, [MnTIPP][T...Magnetic; Coupling2000
62 Miller, Joel StevenIsolation and structural determination of {(1,1,2,2-tetracyano-1,2-ethanediyl)bis[imino(cyanomethylene)]}bis-(cyanamide) ion(2--), [C12N12]2--, a new cyanocarbonThe oxidative degradation of [N(PPh3)2]3[Mnilll(CN)6] leads to the isolation of the unprecedented [C12N12]2- dianion, which is characterized by single-crystal X-ray diffraction and spectroscopic techniques.Cyanogen; Bond; Absorptions1995
63 Poulter, Charles DaleIsoprenyl diphosphate synthases: protein sequence comparisons, a phylogenetic tree, and predictions of secondary structureIsoprenyl diphosphate synthases are ubiquitous enzymes that catalyze the basic chain-elongation reaction in the isoprene biosynthetic pathway. Pairwise sequence comparisons were made for 6 farnesyl diphosphate synthases, 6 geranylgeranyl diphosphate synthases, and a hexaprenyl diphosphate synthase...Catalytic site; Evolution; Farnesyl diphosphate; Geranylgeranyl diphosphate; Prenyltransferase; Substrate binding:1994
64 Miller, Joel Steven; Epstein, Arthur J.Ferrimagnetic resonance in films of vanadium [tetracyanoethanide]x, grown by chemical vapor depositionFerrimagnetic resonance (FMR) measurements in thin films of V[TCNE]x grown by chemical vapor deposition exhibit a series of sharp lines at 300 K. The orientational dependence of these lines is a result of the sample geometry provided the magnetization tracks the applied magnetic field. The FMR inten...Spin; Anisotropy; Magnetization2004
65 Miller, Joel Steven; Epstein, Arthur J.Spin dilution in a ferromagnetic chainWe have systematically introduced spinless defects in the quasi-one-dimensional ferromagnetic system decamethylferrocenium tetracyanoethanide, [FeCp(2*)] [TCNE]. The three-dimensional ordering temperature Tc decreases rapidly with the concentration of spinless sites. The rate of decrease of Tc with...Magnetic; Magnetization; Spinless1992
66 Morse, Michael DavidRotationally resolved spectra of Pt?High-resolution laser-induced fluorescence spectroscopy has been used to investigate the 18 163 cm21 band of Pt2 in a supersonically cooled molecular beam. Rotational constants of the ground and excited states were extracted from the rotationally resolved spectrum and determined to be B0'=0.031 754(...2002
67 Armentrout, Peter B.Effect of kinetic and electronic energy on the reactions of Mn+ with H2, HD and D2Reactions of several electronic states of Mn+ with H2, HD, and D2 have been examined using guided ion beam mass spectroscopy. The excitation function for the ground state of Mn+ ( 75) has two regions: one of very low reactivity at threshold and another more efficient pathway at higher energies. In ...Ion-molecule reactions; Translational energy; Bond energy; Threshold behavior; Endothermic reactions; Metal ions; Manganese; Hydrogen1986
68 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled NiPtResonant two-photon ionization spectroscopy of jet-cooled NiPt has been used to investigate the possibility of <f-electron contributions to the bonding in this species. Based on an abrupt onset of predissociation, the bond strength of NiPt is assigned as D0 (NiPt) = 2.798 ? 0.003 eV. Comparisons of ...1989
69 Miller, Joel StevenPotential technology directions of molecular metalsIn the past decade, anisotropic molecular conductors have been found which possess unusual electrical, optical, magnetic, and in some cases mechanical properties. Exploiting these properties for specific devices is inevitable, and a number of diverse applications of molecular metals have been repor...Molecular metals1979
70 Armentrout, Peter B.Probes of spin conservation in heavy metal reactions: experimental and theoretical studies of the reactions of Re+ with H2, D2, and HDA guided ion beam tandem mass spectrometer is used to examine the kinetic energy dependence of reactions of the third-row transition metal cation, Re1, with molecular hydrogen and its isotopologues. A flow tube ion source produces Re1 in its 7S3 electronic ground state.Endothermic reactions; Transition metal ions; Rhenium ions; Dihydrogen2004
71 Armentrout, Peter B.Thermodynamics of ammonia activation by iron cluster cations: guided ion beam studies of the reactions of Fen+ (n=2-10,14) with ND3The kinetic energy dependences of the reactions of Fen 1 (n52 - 10,14) with ND3 are studied in a guided ion beam tandem mass spectrometer over the energy range of 0-10 eV. Dehydrogenation of ammonia to form FenND1 is found to be efficient and exothermic for n54 in agreement with previous FT-ICR stu...2003
72 Miller, Joel Steven; Epstein, Arthur J.Elastic properties of (N(CH3)3H) (I) (TCNQ)We present the results of a study of the temperature dependence of the Young's modulus and internal friction of (N(CH3 )3H)(I)(TCNQ). The Young's modulus was measured in a direction parallel to the TCNQ (tetracyanoquinodimethane) stacking axis using a vibrating reed technique. The results confirmed ...Metal-like, Conductivity, Magnetic1979
73 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
74 Miller, Joel Steven; Epstein, Arthur J.Photoinduced magnetization in the organic-based magnet Mn(TCNE)x.y(CH2Cl2)Photoinduced magnetization in a magnet based on organic species is reported for the first time. Upon optical excitation in the blue region of spectrum, Mn (tetracyanoethylene)x .y(CH2Cl2) (x=2,y-0.8) exhibits increased magnetic susceptibility at temperatures as high as 75 K, accompanied with photo-i...Absorption; Magnetic; Infrared2002
75 Armentrout, Peter B.Collision-induced dissociation dynamics of the [OCS • C2H2]+ complex. A combined experimental and theoretical studyCollision-induced dissociation (CID) of the [OCS • C2H2]+ complex ion with both Xe and Ar over an energy range of 0 to 10 eV in the center of mass frame is studied using a guided ion beam tandem mass spectrometer. The cross sections of the ionic products observed (C,H2S+, OCS+, C2HJ, and S+) are ...Collision-induced dissociation; Competitive shift; Ethylene Sulfide cation; Kinetic shift; Thioketene cation; Potential energy surface2000
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