UScholar Works
 
Filters: Department: "Materials Science & Engineering" School Or College: "College of Engineering" Collection: "ir_uspace"
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CreatorTitleDescriptionSubjectDate
226 Smith, Grant D.Conformational properties of poly(vinylidene fluoride). A quantum chemistry study of model compoundsThe molecular geometries and conformational energies of model molecules of poly(vinylidene fluoride) (PVDF) have been determined from high-level quantum chemistry calculations and have been used in parametrization of a six-state rotational isomeric state (RIS) model for PVDF. The model molecules inv...Poly(vinylidene fluoride); PVDF; Conformational properties1999
227 Smith, Grant D.Prediction of the linear viscoelastic shear modulus of an entangled polybutadiene melt from simulation and theoryWhile accurate quantum chemistry based potentials,1 improved simulation algorithms, and faster computers have made accurate calculation of chain dynamics in unentangled polymer melts from molecular dynamics simulations possible,2-5 direct calculation of the viscoelastic properties of entangled polym...Polybutadiene melt; Viscoelastic shear; Chain dynamics; Entangled polymers2000
228 Borodin, Oleg; Smith, Grant D.; Bedrov, DmitroPolarizable and nonpolarizable force fields for alkyl nitratesQuantum-chemistry-based many-body polarizable and two-body nonpolarizable atomic force fields were developed for alkyl nitrate liquids and pentaerythritol tetranitrate (PETN) crystal. Bonding, bending, and torsional parameters, partial charges, and atomic polarizabilities for the polarizable force f...Alkyl nitrate; Pentaerythritol tetranitrate; PETN; Polarizable atomic force fields; Nonpolarizable atomic force fields2007
229 Smith, Grant D.Viscoelastic properties of polybutadiene in the glassy regime from molecular dynamic simulationsA thorough understanding of the dynamic?mechanical properties of polymer melts and glasses is key to many, if not most, applications of polymers as well as to the processing of polymers.Polymer melts; Polymer glasses; Molecular dynamic simulations2002
230 Smith, Grant D.Quantum chemistry based force field for simulations of poly(vinylidene fluoride)A classical potential function for simulations of poly(vinylidene fluoride) (PVDF) based upon quantum chemistry calculations on PVDF oligomers has been developed. Quantum chemistry analysis of the geometries and conformational energies of 1,1,1,3,3-pentafluorobutane (PFB), 1,1,1,3,3,5,5,5-octofluoro...Poly(vinylidene fluoride) simulations; PVDF2000
231 Smith, Grant D.; Bedrov, DmitroQuantum-chemistry-based force field for simulations of dimethylnitramineThe molecular geometries and conformational energies of nitramide and dimethylnitramine (DMNA), determined from high-level quantum chemistry calculations, have been used in parametrization of a classical potential function suitable for simulations of DMNA. A thorough investigation of basis set size ...Dimethylnitramine simulations; DMNA; Nitramide; Force field; Molecular dynamics simulations1999
232 Smith, Grant D.Quantum chemistry based force field for simulations of HMXThe molecular geometries and conformational energies of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) and 1,3-dimethyl-1,3-dinitro methyldiamine (DDMD) and have been determined from high-level quantum chemistry calculations and have been used in parametrizing a classical potential function ...HMX simulations; Molecular geometries; Conformational energies; DDMD1999
233 Smith, Grant D.; Borodin, Oleg; Bedrov, Dmitro13C NMR spin-lattice relaxation and conformational dynamics in a 1,4-polybutadiene meltWe have performed molecular dynamics (MD) simulations of a melt of 1,4-polybutadiene (PBD, 1622 Da) over the temperature range 400?273 K. 13C NMR spin?lattice relaxation times (T1) and nuclear Overhauser enhancement (NOE) values have been measured from 357 to 272 K for 12 different resonances. The T...Polybutadiene melt; 13C NMR; Spin-lattice relaxation; Conformational dynamics; Molecular dynamics simulation2001
234 Smith, Grant D.Molecular dynamics of a 1,4-polybutadiene melt. Comparison of experiment and simulationWe have made detailed comparison of the local and chain dynamics of a melt of 1,4-polybutadiene (PBD) as determined from experiment and molecular dynamics simulation at 353 K. The PBD was found to have a random microstructure consisting of 40% cis, 50% trans, and 10% 1,2-vinyl units with a number-av...Polybutadiene melt; Molecular dynamics1999
235 Smith, Grant D.; Bedrov, Dmitro; Borodin, OlegQuantum-chemistry-based potential for poly(ester urethane)We have carried out extensive high-level quantum chemistry studies of the geometry, charge distribution, conformational energies, and hydrogen-bonding energies of model compounds for a family of Estane thermoplastic urethanes (TPUs). Upon the basis of these studies, we have parametrized a classical ...Estane thermoplastic urethanes; TPU; Charge distribution; Confromational energy2003
236 Pugmire, Ronald J.Investigation of the structural conformation of biphenyl by solid state 13C NMR and quantum chemical NMR shift calculationsThe principal values of the 13C chemical-shift tensor (CST) for biphenyl have been determined with the FIREMAT experiment. The internal dihedral angle between the benzene rings in biphenyl is estimated to fall between 10 and 20° on the basis of quantum mechanical calculations of the CST principal v...Carbon-13; Chemical-shift tensor; biphenyl; FIREMAT2001
237 Liu, FengTowards quantitative understanding of formation and stability of Ge hut islands on Si(001)We analyze Ge hut island formation on Si(001), using first-principles calculations of energies, stresses, and their strain dependence of Ge/Si(105) and Ge/Si(001) surfaces combined with continuum modeling. We give a quantitative assessment on strain stabilization of Ge(105) facets, estimate the cr...Ge hut islands; Si(001); First-principles calculations; Heteroepitaxial growth2005-05
238 Stringfellow, Gerald B.Effect of oxygen incorporation in semi-insulating (AlxGa1-x)yIn1-yPDiscusses a study conducted on oxygen-doped, semi-insulating layers of (aluminum-gallium) indium phosphide grown on gallium arsenide using organometallic vapor phase epitaxy. Effect of oxygen doping on semi-insulating layers of the substance; Secondary-ion mass spectrometry measurements; Measured co...Inactive interstitial atoms; Energy-dispersive spectoscopy; intentional oxygen1992
239 Liu, FengThermal roughening of a thin film: a new type of roughening transitionThe equilibrium thermal roughening of thin Ge layers (one and two monolayers) deposited on Si(001) has been investigated with low-energy electron microscopy. A Ge-coverage-dependent roughening is observed. For two monolayers, the temperature at which imaging contrast is lost due to surface roughness...Thermal roughening; Roughening transition; Heteroepitaxial growth2000-09
240 Liu, FengEnhanced growth instability of a strained film on wavy substrateWe demonstrate that the growth of a strained film is inherently less stable on a wavy substrate than on a flat substrate. For small surface undulation, the lowest strain energy state is for the film surface to adopt the same wavelength as the substrate surface in an antiphase configuration at the ea...Growth instability; Strained film; Wavy substrate; Strain induced self-assembly2008
241 Stringfellow, Gerald B.Te doping of GaInP: ordering and step structureThe donor Te has been added to GaInP during organometallic vapor phase epitaxial growth using the precursor diethyltelluride. In agreement with previous studies, the addition of high Te concentrations leads to the elimination of the CuPt ordering observed in undoped layers. The degree of order is es...Epitaxial growth; Heterostructures; Growth parameters1999-04-01
242 Scarpulla, MichaelEffect of film thickness on the incorporation of Mn interstitials in Ga1-xMnxAsWe have investigated the effect of film thickness on the distribution of Mn atoms at various lattice sites in Ga1−xMnxAs thin films. We find that the growth surface acts as a sink facilitating the outdiffusion of Mn interstitials sMnId, and thus reducing its concentration in the film. The outdiffu...Interstitials; Gallium arsenide2005
243 Stringfellow, Gerald B.Surface photoabsorption study of the effect of substrate misorientation on ordering in GaInPSubstrate orientation strongly affects Cu-Pt ordering in Ga0.5In0.5P layers grown by organometallic vapor phase epitaxy. In situ surface photoabsorption SPA measurements were used to measure the concentration of 1 10-oriented P dimers, characteristic of the 2 4 reconstructed surface, as a functio...P-dimer concentration; Photoluminescence measurements; Surface reconstruction1996-04-15
244 Stringfellow, Gerald B.GaInAsSb metastable alloys grown by organometallic vapor phase epitaxyGa1-xlnx As1-ySby alloys have been grown by organometallic vapor phase epitaxy using trimethyl compounds of Ga, In, As, and Sb(TMGa, TMIn, TMAs, and TMSb) plus AsH3 in an atmospheric pressure, horizontal, infrared heated reactor. For the first time, alloys near the center of the region of solid immi...Organometallic; Alloys; Vapor phase epitaxy1986
245 Liu, FengMagnetization on vicinal ferromagnetic surfacesUsing Ising model Monte Carlo simulations, we show a strong dependence of surface magnetization on surface miscut angle. For ferromagnetic surfaces, when surface spin exchange coupling is larger than that of the bulk, the surface magnetic ordering temperature decreases, toward the bulk Curie tempera...Vicinal ferromagnetic surfaces; Surface magnetization; Surface miscut angle1997
246 Tiwari, AshutoshRoom-temperature solid-state radiation detectors based on spintronicsIn this paper we are presenting a unique approach to solve the thermal background problem encountered in semiconductor nuclear detectors. Our approach addresses above challenge by making a shift from 'electronic detection mechanism' to 'spintronic detection mechanism'. The proposed methodology is ba...2012-01-01
247 Smith, Grant D.Molecular dynamics simulation studies of the influence of imidazolium structure on the properties of imidazolium/azide ionic liquidsAtomistic molecular dynamics simulations were performed on 1-butyl-3-methyl-imidazolium azide [bmim][N3], 1-butyl-2,3-dimethylimidazolium azide [bmmim][N3], and 1-butynyl-3-methylimidazolium azide [bumim][N3] ionic liquids. The many-body polarizable APPLE&P force field was augmented with parameters ...2012-01-01
248 Scarpulla, MichaelPulsed and continuous wave solid phase laser annealing of electrodeposited CuInSe2 thin filmsCu(In,Ga)Se2 (CIGS) thin film photovoltaic absorber layers are primarily synthesized by vacuum based techniques at industrial scale. In this work, we investigate non-vacuum film synthesis by electrochemical deposition coupled with pulsed laser annealing (PLA) and or continuous wave laser annealing (...2012-01-01
249 Liu, FengSpatial and energy distribution of topological edge states in single Bi(111) bilayerBy combining scanning tunneling microscopy and spectroscopy, angle-resolved photoemission spectroscopy, and density functional theory band calculations, we directly observe and resolve the one-dimensional edge states of single bilayer (BL) Bi(111) islands on clean Bi2Te3 and Bi(111)-covered Bi2Te3 s...2012-01-01
250 Liu, FengA three-layer-mesh bridging domain for coupled atomistic-continuum simulations at finite temperature: formulation and testingAlthough concurrent multiscale methods have been well developed for zero-temperature simulations, improvements are needed to meet challenges pertaining to finite-temperature simulations. Bridging domain method (BDM) is one of the most efficient and widely-used multiscale atomistic-continuum techniqu...2014-01-01
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