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CreatorTitleDescriptionSubjectDate
51 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
52 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
53 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
54 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
55 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
56 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
57 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
58 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
59 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
60 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
61 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
62 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
63 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
64 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
65 Morse, Michael DavidOptical spectroscopy of jet-cooled NiSiThe electronic states of gaseous diatomic NiSi have been investigated using the combined techniques of resonant two-photon ionization spectroscopy, dispersed fluorescence spectroscopy, and density functional computations. A single electronic band system, designated as the [8.0]1?X 1?+ system, has be...2003
66 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
67 Miller, Joel StevenCharacterization of novel TCNQ and TCNE 1 : 1 and 1 : 2 salts of the tetrakis(dimethyamino) ethylene dication, [{(CH3)2N}2C-C{N(CH3)2}2]2+Addition of TCNQ to a solution of tetrakis(dimethylamino)ethylene in MeCN produces the salt [TDAE][TCNQ]2; the dipositive cation, [{(CH3)2N}2C-C{N(CH3)2}2]2+, is nonplanar, with a dihedral angle of 63.9(o), while the TCNQ anions crystallize as [TCNQ]2 2- dimers with an interplanar separation of 3.1...Electron; Oxidations; Transfer1996
68 Miller, Joel Steven; Epstein, Arthur J.Molecule-based magnets - an overviewMolecule-based* magnets are a broad, emerging class of magnetic materials that expand the materials properties typically associated with magnets to include low density, transparency, electrical insulation, and low-temperature fabrication, as well as combine magnetic ordering with other proper...Spin; Magnetization; Magnetic ordering2000
69 Miller, Joel Steven; Epstein, Arthur J.Anomalous relaxation in a quasi-one-dimensional fractal cluster glassThe low-temperature spin glass state of the quasi-1D organic-based magnet [MnTPP]+[TCNE]- .x(1,3-C6H4Cl2) has unusually long relaxation times due to frustration induced by dipole-dipole interactions between fractal spin clusters. This long relaxation is investigated with in-field relaxation measurem...Sweep rate; Bifurcation; Magnetization2004
70 Miller, Joel StevenFormation of a zwitterionic donor-acceptor compound based on N,N,N',N'-tetramethly-p-phenylenediamine and 7,7,8,8-tetracyanoperfluoro-p-quinodimethaneThe reaction of the donor N,N,N',N'- tetramethyl-p-phenylenediamine (TMPD) with the acceptor 7,7,8,8-tetracyanoperfluoro-p-quinodimethane (TCNQF4) has led to the isolation of a novel type of zwitterionic donor-acceptor compound whose structure has been determined by X-ray crystallography.Ccrystals; Single bond1988
71 Voth, Gregory AlanMultiscale coarse-graining of the protein energy landscapeA variety of coarse-grained (CG) models exists for simulation of proteins. An outstanding problem is the construction of a CG model with physically accurate conformational energetics rivaling all-atom force fields. In the present work, atomistic simulations of peptide folding and aggregation equilib...2010-06-24
72 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
73 Miller, Joel StevenFar-infrared powder spectrum of (N(CH3)3D)(I)(TCNQ)We present the powder absorption spectrum of (TMA)(I)(TCNQ) in the far-infrared as a function of temperature. Below 160 K new absorption features appear and others increase in intensity. This behaviour supports the electron- neutron-diffraction evidence of a distortion on the TCNQ chains below the f...Conductivity, Crystals, Electrons1983
74 Morse, Michael DavidSpectroscopy of AlAr and AlKr from 31 000 cm-1 to the ionization limitSpectra of jet-cooled AlAr and AlKr have been collected over the range from 31 000 cm -? to the ionization limit, using the technique of resonant two-photon ionization spectroscopy with mass spectrometric detection. Adiabatic ionization potentials have been accurately measured for both molecules, an...1992
75 Morse, Michael DavidResonant two-photon ionization spectroscopy of LiCuJet-cooled LiCu has been investigated using resonant two-photon ionization spectroscopy. A long vibrational progression was observed and identified as the [20.5] 1?+? X 1?+ band system. Ten bands of the system were rotationally resolved for 7Li63Cu, giving bond lengths of r0=2.2618(3) ? for the X 1?...1997
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