UScholar Works
 
Filters: Date: "1999" Department: "Chemistry" Collection: "ir_uspace"
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CreatorTitleDescriptionSubjectDate
1 Miller, Joel StevenCollinear ferromagnetism and spin orientation in the molecule-based magnets M[N(CN)2]2 (M=Co,Ni)Zero-field unpolarized neutron powder diffraction has been used to study the low-T magnetic structure and T-dependent crystal structure of M[N(CN)2]2 (M=Co,Ni). Both compounds show collinear ferromagnetism with spin orientation along the c axis. The results provide the determination of a complete ma...Magnetic; Diffraction; Structure1999
2 Miller, Joel StevenCrystal structure and magnetic properties of [Fe{N(CN)2}2(MeOH)2] a 2-D layered network consisting of hydrogen-bonded 1-D chainsA novel 2-D layered network structure [Fe{N(CN)2}2(MeOH)2] was synthesized and characterized by X-ray crystallography, vibrational, and magnetic susceptibility. The neutral 2-D stair-like framework consists of hydrogen-bonded infinite 1-D {Fe[N(CN)2]2} ribbons that pack in a staggered arrangement wh...Solids; Dicyanamide; Ordering1999
3 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
4 Truong, ThanhDirect ab initio dynamics studies of the hydrogen abstraction reactions of hydrogen atom with fluoromethanesA direct ab initio dynamics study on the gas-phase reactions of atomic hydrogen with different fluoromethanes has been carried out. The thermal rate constants were calculated using canonical variational transition state (CVT) theory augmented by multidimensional semiclassical zero and small curvatur...Hydrogen abstraction reactions; Gas-phase reactions; Fluoromethanes; Thermal rate constants; Moller?Plesset perturbation theory; Hybrid density functional theory1999
5 Truong, ThanhHigh level ab initio and density functional theory evaluation of combustion reaction energetics: NO2 and HONO elimination from dimethylnitramineDimethylnitramine (DMNA) is used as a model system for investigating accurate and efficient electronic structure methods for nitramines. Critical points on the potential energy surfaces of DMNA, CH3NCH3, CH3NCH2, NO2, HONO, and the transition state to HONO elimination were located through geometry o...Dimethylnitramine; DMNA; Nitramines; Combustion reaction energetics1999
6 Truong, ThanhImportance of polarization in simulations of condensed phased energetic materialsAn embedded cluster model is used to estimate the molecular dipole moment of crystalline dimethylnitramine (DMNA). The electrostatic potential due to the crystal is included in the calculation via the SCREEP (surface charge representation of the electrostatic embedding potential) approach. The resul...Dimethylnitramine; DMNA; Embedded cluster model1999
7 Wight, Charles AlbertKinetic study of stabilizing effect of oxygen on thermal degradation of poly(methyl methacrylate)The thermal degradation of poly(methyl methacrylate) (PMMA) has been studied in both pure nitrogen and oxygen-containing atmospheres. The presence of oxygen increases the initial decomposition temperature by 70 °C. The stabilizing effect of oxygen may be explained by forming thermally stable radica...Poly(methyl methacrylate); PMMA; Thermal degradation; Isoconversional method1999
8 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
9 Wight, Charles AlbertKinetics of thermal decomposition of cubic ammonium perchlorateThe methods of thermogravimetric analysis (TGA) and differential scanning calorimettry (DSC) have been used to study the thermal decomposition of ammonium perchlorate (AP). TGA curves obtained under both isothermal and nonisothermal conditions show a characteristic slowdown at the extents of convers...Thermal decomposition; Cubic ammonium perchlorate; Differential scanning calorimetry1999
10 Miller, Joel StevenMnII(N3)2(pyrazine).A 2-D layered structure consisting of ferromagnetically coupled 1-D {Mn(U-1,1-N3)2}n chainsMn(N3)2(pyz) (pyz = pyrazine) consists of ferromagnetically coupled linear chains of {Mn(N3)2}n comprised of u-1,1-azido bridges together with u-pyz ligands to afford 2-D planar layers.Ferromagnetic; Coupling; Magnetic1999
11 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled PdCThe first optical investigation of the spectra of diatomic PdC has revealed that the ground state has ?=0+, with a bond length of r0=1.712?. The Hund?s case (a) nature of this state could not be unambiguously determined from the experimental data, but dispersed fluorescence studies to be reported in...1999
12 Morse, Michael DavidResonant two-photon ionization spectroscopy of jet-cooled PtSiJet-cooled diatomic PtSi, produced in a laser ablation supersonic expansion source, has been spectroscopically investigated between 17 400 and 24 000 cm-1 by resonant two-photon ionization spectroscopy. Two vibrational progressions are observed and identified as the [15.7]?'=1 ?X 1?+ and [18.5]?'=1 ...1999
13 Morse, Michael DavidRydberg and pulsed field ionization-zero electron kinetic energy spectra of YOA spectroscopic study of the Rydberg states of YO accessed from particular rotational levels of the A 2II1/2, v=0 state has been combined with a pulsed field ionization, zero electron kinetic energy (PFI-ZEKE) investigation. The results provide accurate values of the ionization energy of YO, ioniz...1999
14 Armentrout, Peter B.; Morse, Michael DavidRydberg and pulsed field ionization-zero electron kinetic energy spectra of YOA spectroscopic study of the Rydberg states of YO accessed from particular rotational levels of the A²Π½, v=0 state has been combined with a pulsed field ionization, zero electron kinetic energy (PFI-ZEKE) investigation. The results provide accurate values of the ionization energy of YO, ionizati...Ionization energy; Rydberg spectra; Yttrium monoxide1999
15 Miller, Joel StevenSpin crossover behavior of [FeII(isoxazole)6][BF4]2--a structural study[FeII(isoxazole)6][BF4]2 undergoes two reversible spin crossover transitions at 91 and 192 K and the single crystal structure determination reveals two different iron sites, Fe1 and Fe2, in a 1 : 2 ratio, with Fe1 attributed to the 91 K transition, and Fe2 attributed to the 192 K transition. This is...Transition; Magnetic; Temperature1999
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