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276 Stang, Peter J.One-dimensional coordination polymers based on first-row transition metals: a solid-state study of weak backbone interactionsWe present further data on the solid-state structures of one-dimensional coordination polymers based upon dipositive transition metal hexafluoroacetylacetonate (hfacac) complexes. A variety of linking subunits are employed in order to investigate and probe the relatively weak interactions that make...Hexafluoroacetylacetonate complexes; Coordination polymers2001
277 Morse, Michael DavidSpectroscopy of diatomic ZrF and ZrCl: 760 ? 555 nmThe optical spectrum of diatomic ZrF has been investigated, with transitions recorded in the range from 14 700 to 18 000 cm?1. Many bands have been observed, several of which can be grouped into three band systems. Rotationally resolved investigations are hampered by perturbations that are rampant ...2011
278 Morse, Michael DavidDispersed fluorsecence spectroscopy of AINi, NiAu, and PtCuDispersed fluorescence studies of AlNi, NiAu, and PtCu have been performed, providing spectroscopic information about the ground and low-lying excited electronic states. Vibrational frequencies are reported for the ground X 2?5/2 state of all three molecules. In the case of AlNi, fluorescence to all...2003
279 Morse, Michael DavidResonant two-photon ionization spectroscopy of the 13-electron triatomic Si2NResonant two-photon ionization spectra of 28Si2N, 28,29Si2N, and 28,30Si2N have been collected between 32 000 cm-1 and 36 000 cm-1. A fit of the rotationally resolved spectrum of the most intense band of 28Si2N at 34 314 cm-1 reveals the transition to be 2?+u ? X~ 2IIg,1/2- A molecular orbital analy...1996
280 Miller, Joel Steven; Epstein, Arthur J.Ferromagnetic properties of one-dimensional decamethylferrocenium tetracyanoethylenide (1:1): [Fe(n5-C5Me5)2].+[TCNE].-[Fe(C5Me5)2].+ [TCNE].-- has been characterized by magnetic susceptibility to possess dominant ferromagnetic interactions; its structure has been determined by X-ray crystallography.Susceptibility; Crystal; Magnetic1986
281 Armentrout, Peter B.Guided ion beam studies of the reaction of Nin+ (n=2-16) with D2: nickel cluster-deuteride bond energiesThe kinetic-energy dependences of the reactions of Nin+ (n=2-16) with D2 are studied in a guided ion beam tandem mass spectrometer. The products observed are NinD+ for all clusters and NinD2 + for n=5-16. Reactions for formation of NinD+ are observed to exhibit thresholds, whereas cross sections for...Metal clusters; Nickel ions; Bond energies; Deuterides; Collision-induced dissociation; Endothermic reactions2002
282 Miller, Joel StevenPressure dependence of magnetic ordering temperature for decamethylferrocenium tetracyanoethenideIt has been demonstrated that the linear-chain charge-transfer salt, decamethylferrocenium tetracyanoethanide (DMeFc) (TCNE), is a ferromagnet with a transition temperature of -4.8 K. This low-temperature 3D ordering has been attributed to a strong intrachain and a weak interchain interaction. To...Ferromagnetic; Transition; Antiferromagnetic1993
283 Morse, Michael DavidSpectroscopic analysis of the open 3 d subshell transition metal aluminides: AIV, AICr, and AICoThree open 3d subshell transition metal aluminides, AlV, AICr, and AlCo, have been investigated by resonant two-photon ionization spectroscopy to elucidate the chemical bonding in these diatomic molecules. The open nature of the 3d subshell results in a vast number of excited electronic states in th...1994
284 Miller, Joel StevenIsomeric conformations in a pentaco-ordinated ruthenium compound: crystal and molecular structures of the orange and violet isomers of (Ph3P)2[(CF3)2C2S2]Ru(CO)Summary The molecular conformations of two square pyramidal species, one violet the other orange, both composition (Ph3P)2[(CF3)2C2S2]Ru(CO) are described.Pyramidal, Radiation,1973
285 Olson, Randall J.; Coldwell, Karin D.; Compton, Bruce J.; Giddings, John C.Sedimentation field-flow fractionation: a method for studying particulates in cataractous lensIt is shown that the technique of sedimentation field-flow fractionation (sedimentation [sed] FFF) can be used to determine the particle content and particle size distribution of normal and cataractous lenses. A 31-year-old normal human lens, for example, showed a particle content of 1.5% by weight ...Fractionation; Cataractous Lens; Particulates1984
286 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
287 Miller, Joel StevenFar-infrared properties of trimethylammonium iodide tetracyanoquinodimethaneWe present the powder absorption spectrum of (TMA) (I)(TCNQ) in the far-infrared as a function of temperature. Below 16 K new absorption features appear and others increase in intensity. This behaviour supports the electron and neutron diffraction evidence of a distortion on the TCNQ chains below...Trimethylammonium iodide tetracyanoquinodimethane; TCNQ1983
288 Morse, Michael DavidLaser vaporization generation of the SiB and SiAi radicals for matrix isolation electron spin resonance studies: comparison with theoretical calculations and assignment of their electronic ground states as X ??The first experimental spectroscopic study of the SiB and SiAl diatomic radicals is reported. Electron spin resonance results indicate that both molecules have X 4? ground electronic states, in agreement with earlier theoretical calculations. The SIB and SiAl radicals were generated in neon matrices...1993
289 Miller, Joel Steven; Epstein, Arthur J.Anomalous magnetoresistance in high-temperature organic-based magnetic seminconducting V(TCNE)x filmsAnomalous positive magnetoresistance (MR) in high temperature organic-based magnet V(TCNE)x (TCNE=tetracynoethylene) thin films is reported. MR increases linearly with applied magnetic field and shows a maximum at the ferrimagnetic ordering temperature. The suggested roles of oppositely spin pola...Spin; Ferrimagnetic; Resistance2003
290 Miller, Joel Steven; Epstein, Arthur J.Novel co-operative magnetic properties of decamethylmanganocenium 2,3-dichloro-5,6-dicyanobenzoquinoneide, 3[Mn(C5Me5)2]:+[DDQ].-The electron-transfer salt 3[Mn(C5Me5)2]: + [DDQ].-, isomorphous to orthorhombic [Fe(C5Me5)2].+[DDQ].-, has been prepared. It exhibits a complex field-dependent magnetic phase diagram at low temperatures with evidence for ferromagnetic coupling as well as a low moment state below 4 K for zero-field ...Ferromagnetic; Electron-transfer salt; Powder diffraction1991
291 Miller, Joel StevenDimetallic complexes derived from a novel dinucleating chelating symmetric triazole ligand; crystal strcutrue,magnetic properties and ESR study of Bis[μ-3,5-diacetlyamino-1,2,4-triazolato-O',N1,N2,O"]bis[nitrato)(aqua)-copper(II)]Reaction of 3,5-diacetylamino-1,2,4-triazole (Hdaat) with copper(II), nickel(II) and cobalt(II) salts yields dinuclear co-ordination compounds, which were spectroscopically characterized. The crystal and molecular structure of one of the compounds, bis[u-3,5-diacetylamino-1,2,4-triazolato-0'_x0001_,...Susceptibility; Orbitals; Compounds1999
292 Voth, Gregory AlanFurther developments in the local-orbital density-functional-theory tight-binding methodQuantum-mechanical methods have become increasingly reliable as a complementary tool to experimental research. A variety of methods exist ranging in complexity from semiempirical methods to density-functional-theory (DFT) methods [using either the local-density approximation (LDA) or the generalize...Sankey-Niklewaki method; Fireball method; Pseudopotential; Exchange-correlation interactions; Gallium nitride; H20 dimer; Copper; gas-phase HMX2001-10
293 Armentrout, Peter B.Kinetic energy dependence of Al+ + O2→AlO+ + OThe endothermic reaction of Al+ with O2 is studied using a guided ion-beam apparatus. The reaction cross section is measured as a function of kinetic energy from 0 to 20 eV. The threshold energy for the reaction, E0, is determined from an empirical model to be 3.64 ± 0.04 eV.Ion-molecule reactions; Translational energy; Threshold behavior; Endothermic reactions; Aluminum; Oxygen1986
294 Miller, Joel Steven; Epstein, Arthur J.Specific heat of decamethylferrocenium tetracyanoethanide (DMeFc)(TCNE)We report the specific heat C(T) of (DMeFc)(TCNE) for temperatures 3 K < T < 50 K. We observe an anomaly at Tc-4.82 K corresponding to a transition to a three-dimensional (3D) macroscopic ferromagnet. A broad maximum at = 15 K corresponds to an exchange interaction of J = 35 K along the chain axis. ...Temperature; Ferromagnetic; Magnetic1989
295 Poulter, Charles DaleIsolation of Schizosaccharomyces pombe isopentenyl diphosphate isomerase cDNA clones by complementation and synthesis of the enzyme in Escherichia coliIsopentenyl diphosphate (IPP) isomerase catalyzes an essential activation step in the isoprene biosynthetic pathway. The Saccharomyces cerevisiae gene for IPP isomerase, IDI1, was recently isolated and characterized (Anderson, M. S., Muehlbacher, M., Street, I. P., Proffitt, J., and Poulter, C. D. (...Carbon-Carbon; Biosynthesis; Genetics1995-05-12
296 Morse, Michael DavidSpectroscopic studies of the jet-cooled aluminum trimerGas phase spectroscopic investigations of the jet-cooled aluminum trimer are reported using the technique of resonant two-photon ionization with mass spectrometric detection. A discrete band system in the 5200-6100 ? region is observed, consisting of an extended vibrational progression in a single ...1987
297 Armentrout, Peter B.Relative and absolute bond dissociation energies of sodium cation-alcohol complexes determined using competitive collision-induced dissociation experimentsAbsolute (R1OH)Na+-(R2OH) and relative Na+-(ROH) bond dissociation energies are determined experimentally by competitive collision-induced dissociation of (R1OH)Na+(R2OH) complexes with xenon in a guided ion beam mass spectrometer. The alcohols examined include ethanol, 1-propanol, 2-propanol, n-but...2010
298 Miller, Joel StevenFerrimagnetic ordering of a methylthio-substituted planar porphyrin based electron transfer salt, octakis(2,3,7,8,12,13,17,18-methylthio)porphyrinatomanganese(III) tetracyanoethanideThe direct redox reaction between tetracyanoethylene (TCNE) and a planar porphyrinatomanganese(II), octakis(2,3,7,8,12,13,17,18-methylthio)porphyrinatomanganese(II), MnIIOMTP, produced a polymeric electron transfer salt (ETS), that has been structurally and magnetically characterized. The ETS belon...Magnetic; Temperature; Coupling2000
299 Miller, Joel Steven; Epstein, Arthur J.Noise in highly correlated commensurate charge transfer saltsWe present the results of a study of the frequency (f) dependent noise power for commensurate charge transer salts with strong coulomb repulsion. f-1 noise is observed with increasing currents. Excess f-1 noise is measured for samples which were chemically doped to form solitons. Frequency indepe...Noise power; Charge-transfer salts1983
300 Morse, Michael DavidThe ?IIou ?X ???g band system of jet-cooled Ti?A band of jet-cooled ??Ti? has been located in the near infrared by resonant two-photon ionization spectroscopy. Rotational analysis has shown the band to be an ?? =O* ???=1 transition, which is consistent with the 3??g, ground state proposed by Bauschlicher ef al. [J. Chem. Phys. 95, 1057 ( 1991)]...1992
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