... ADP023770. Title : ab-Initio Molecular Dynamics Simulations of Molten Ni-Based Superalloys. Descriptive Note : Conference paper. ...
DTIC Science & Technology
... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : New AB Initio Based Density ...
... Title : Ab-Initio Molecular Dynamics Simulations of Molten Ni-Based Superalloys. Descriptive Note : Conference paper (preprint). ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab-Initio Molecular Dynamics Simulations ...
... Results of this study substantiate findings from an earlier quantum chemical study using a lower ... for (I) and (II) based on the earlier ab initio study. ...
Two approaches for directly computing a molecular heat of formation based on sophisticated ab initio
NASA Technical Reports Server (NTRS)
Metal atom clusters are studied based on the application of ab initio quantum mechanical approaches.
Quantum mechanical-based (or ab initio) methods are used to predict the stability properties of materials although their application is limited to relatively simple systems in terms of structures and number of alloy components. However thermodynamics of c...
National Technical Information Service (NTIS)
Ab initio calculations of single and double differential cross sections for ionization by fast, charged particles within the framework of Born approximation are presented. In addition, a semiempirical method based on the asymptotic Bethe-Boron expansion i...
A global search for possible LiF cluster structures is performed up to (LiF)(8). The method is based on simulated annealing, where all the energies are evaluated on the ab initio level. In addition, the threshold algorithm is employed to determine the energy barriers for the transitions among these structures, for the cluster (LiF)(4), ...
PubMed
Structural and thermal properties of small lithium clusters are studied using ab initio-based Monte Carlo simulations. The ab initio scheme uses a Hartree-Fock/density functional treatment of the electronic structure combined with a jump-walking Monte Car...
... Keywords: ab initio calculations · energetic materials · ionic liquids · lanthanides · nitrate complexes ... Page 9. Lanthanide-Based Ionic Liquids ...
... This study involves: Ab-initio crystal orbitals and polymer orbitals; Ab-initio coupled cluster program; Ab-initio quantum chemical calculations and ...
A initio quantum chemical methods are seeing increased application in a large variety of real-world problems including biomedical applications ranging from drug design to the understanding of environmental mutagens. The vast majority of these quantum chem...
... The interactions for DTP, DTC and Fe2O3 are evaluated based on a force field derived from fitting to ab initio quantum chemical calculations of ...
An ab initio calculation is needed to obtain a more reliable theoretical estimate. .... piezoelectric properties of [II-V semiconductors ...
NASA Website
based on the application of ab initio quantum mechanical approaches. This ... work will be appearing in the International Journal of Quantum Chemistry. (2) ...
... AOARD-054095 Hiroshi Mizuseki, Rodion V. Belosludov, Amir A. Farajian, Tomoki Uehara, and Yoshiyuki Kawazoe Institute ...
... Abstract : Electronic structure calculations using theoretical methods based on the linked-diagram theorem are reported for a series of dissociation ...
The unimolecular decay lifetimes of several vibrational states of HN2 are determined on the basis of
... Abstract : The results of ab initio calculations based on the density-functional method and using the norm-conserving pseudopotentials for the ...
on "Quantum Chemical Calculation of the Equilibrium Structures of Small ... based on the application of ab initio quantum mechanical approaches. This ...
... softening of Al-based fcc alloys using ab initio Korringa-Kohn-Rostoker augmented-spherical-wave electronic structure calculations is discussed. ...
... solidification; Density; Nickel alloys; Liquids; Diffusion-liquid; ... erties of molten Ni-based alloys. The simulation method evolves ionic positions using ...
... At present experimental data for ternary Ni-Al-W alloys is not available, and estimates of the accuracy of the Mukai model for liquid density in this ...
... dependent densities in the multicomponent RENE-N4 superalloy, and estimates of the accuracy of the Mukai model for liquid density in this system ...
Dec 8, 2009 ... We examine different molecular structures of nitrogen based on recent observations for analog systems. A structure with Immm symmetry and ...
... Personal Author(s) : Mizuseki, Hiroshi ; Belosludov, Rodion V. ; Farajian, Amir A. ; Uehara, Tomoki ; Kawazoe, Yoshiyuki. Handle / proxy Url : ...
Mar 1, 2011 ... Conformational Characteristics of Poly(tetrafluoroethylene) (PTFE) Based Upon Ab Initio Electronic Structure Calculations on Model Molecules ...
... Title : Chalcopyrite Magnetic Semiconductors: An Ab-Initio Study of Their Structural, Electronic and Magnetic Properties. ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... COMPENDIUM OF AB INITIO CALCULATIONS ...
... Accession Number : ADA219907. Title : An Ab Initio Study of the Geometry and Rotational Barrier of 4- Phenylimidazole. ...
... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : Ab Initio Calculations of the ...
... Title : Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields. ...
... Title : AB Initio Quantum Chemical Investigations of Solubilities in Supercritical Solutions. Descriptive Note : Conference Paper,. ...
Polynomial expressions for the elastic tensor coefficients, the bulk, the shear and Young�s moduli, the speed of sound for longitudinal and transverse waves, the equation of state and the x coordinate of the sulfur atom in pyrite are reported based on ab initio calculations in the range of 0-135 GPa. Comparison with published ...
NASA Astrophysics Data System (ADS)
Quantum mechanical-based (or ab initio) methods are used to predict the stability properties of materials although their application is limited to relatively simple systems in terms of structures and number of alloy components. However thermodynamics of complex multi-component alloys requires a more versatile approach afforded within ...
Energy Citations Database
... Title : AB Initio Study of the Electronic Magnetic Circular Dichroism ... functions are determined using as initio quantum chemical techniques including ...
The rotational mechanism of the NH{sub 4}{sup +} ion in water is analyzed by using both semiempirical (AM1) and ab initio (6-31G* SCF level) methods. AM1 predicts rapid rotation at any degree of first solvent shell hydration from n = 1-6. These results are considered artifactual since AM1 favors ion-water structures of a type not found in ...
A simple method to estimate the atomic degree Hessian matrixof a nanosystem is presented. The estimated Hessian matrix, based on themotif decomposition of the nanosystem, can be used to accelerate abinitio atomic relaxations with speedups of 2 to 4 depending on the sizeof the system. In addition, the programing implementation for using thismethod in a standard ...
DOE Information Bridge
Due to recent advances in methods and computers, the accuracy of ab calculations has reached a point
isomer. Ab initio calculations also were performed to aid in the spectral assignments for neopentyl, t which were based on extensive quantum-chemical calculations. Since there are approximately 170 stable in C5H11O2, rather than needing to rely on ab initio calculations to make predictions
E-print Network
� � � SBOP +44 +10 786 796 EDTB -45 +16 416 432 MBPP: mixed-basis pseudopotential method CPMD: Car of this boundary using the ab initio, density functional theory based, mixed-basis pseudopotential method [39- denum and niobium. First, the ab initio mixed-basis pseudopotential (MBPP) ...
The vibrational frequencies of the electronic ground state of resorcinol have been determined via laser-induced dispersed fluorescence spectroscopy. An assignment based on comparison with ab initio calculations on the MP2 and B3LYP (6-311 G (d,p)) level is presented.
Ab-initio study of zone centre phonons in rare-earth hexaborides, MB6, has been made using self-consistent density functional method based on norm-conserving pseudo-potentials and numerical atomic orbitals as basis set. Calculated values of zone centre phonons are in fair agreement with the experimental results.
The effects of electron-hole interaction on the optical properties of a variety of materials have been calculated using an ab initio method based on solving the Bethe-Salpeter equation. Results on selected semiconductors, insulators, and semiconducting polymers are presented. In the cases of alpha-quartz (SiO2) and ...
High level ab initio calculations have been carried out on the C-13 - C-12 kinetic isotope effect of the CH4 + OH reaction in the atmosphere. The results agree quite well with both the absolute value of the isotope effect and the temperature dependence of the effect, based on new experimental data. The calculated kinetic isotope effect ...
Based on ab initio pseudopotential calculations, the results of investigations of the lattice dynamics of silver halides AgHal (Hal = Cl, Br, I) are presented. Equilibrium lattice parameters, phonon spectra, frequency densities and effective atomic-charge values are obtained for all types of crystals under study.
We present a formulation of ab initio electronic structure calculations in a finite magnetic field, which retains the simplicity and efficiency of techniques widely used in first principles molecular dynamics simulations, based on plane-wave basis sets and Fourier transforms. In addition we discuss results obtained with this method for ...
The project began March 13, 2006, allocated for three years, and received a one year extension from March 13, 2009 to March 12, 2010. It has now completed 48 of 48 total months. The project was focused on using ab initio methods to gain insights into radi...
The ab initio no-core shell model (NCSM) is extended to include a realistic three-body interaction in calculations for p-shell nuclei. They present results of first applications using the Argonne V8' nucleon-nucleon (NN) potential and the Tucson-Melbourne...
Ab Initio QM/MM Study of Class A -Lactamase Acylation: Dual Participation of Glu166 and Lys73 ) and an energetically favorable transfer of a proton from Lys73 to Glu166, through the catalytic water molecule and Ser70. This gives unprotonated Lys73 and protonated Glu166. Tetrahedral formation ensues in a concerted
We present a theoretical investigation of the electronic structure of an InAs monomolecular plane inserted in bulk GaAs. Our calculations are based on the ab initio self-consistent pseudopotential method. Both electrons and holes are found to be strongly ...
An accurate and efficient molecular alignment technique is presented based on first principle electronic structure calculations. This new scheme maximizes quantum similarity matrices in the relative orientation of the molecules and uses Fourier transform techniques for two purposes. First, building up the numerical representation of true ab ...
PubMed Central
The framework of ab initio density-functional theory (DFT) has been introduced as a way to provide a seamless connection between the Kohn-Sham (KS) formulation of DFT and wave-function based ab initio approaches [R. J. Bartlett, I. Grabowski, S. Hirata, and S. Ivanov, J. Chem. Phys. 122, 034104 ...
For the equilibrium immiscible Fe-Cu system, ab initio calculations using the projector augmented wave method identify the relatively stable structures of the metastable Fe25Cu75 and Fe50Cu50 alloys to be both of fcc and determine their corresponding lattice constants and cohesive energies. Some of the ab initio ...
... AB-INITIO SIMULATION OF a/2110> ... 4. TITLE AND SUBTITLE AB-INITIO SIMULATION OF a/2110> SCREW DISLOCATIONS γ-TiAl 5c. ...
... ADP012740 TITLE: Ab Initio Study on Spin Polarization of III-V Compound Tips ... Ab initio study on spin polarization of III-V compound tips ...
Ab initio electronic structure methods can supplement CALPHAD in two major ways for subsequent applications to stability in complex alloys. The first one is rather immediate and concerns the direct input of ab initio energetics in CALPHAD databases. The o...
...with this part. The certificate shall be void ab initio for those vehicles causing the...issued, and the certificate may be deemed void ab initio. (C) The manufacturer...with this part. The certificate shall be void ab initio for those vehicles causing...
Code of Federal Regulations, 2010
We present pair potentials for fluorinated methanes and their dimers with CO2 based on ab initio potential energy surfaces. These potentials reproduce the experimental second virial coefficients of the pure fluorinated methanes and their mixtures with CO2 without adjustment. Ab initio ...
The compression of Mg2SiO4, (?-forsterite, ?-wadsleyite and ?-ringwoodite) up to 24 GPa pressure is analysed with the help of two equation of state :first Birch-Murnaghan and second based on ab-initio pseudopotential approach. It is concluded that the EOS based on ab-initio pseudopotential approach show the ...
An ab initio density functional theory-based study of the electronic band structure, the elastic, electric, elastoelectric, and linear and nonlinear optical properties of the new ion conductor LiB6O9F, has been performed. The computed band structure reveals a wide direct band gap. The coefficients of the second order nonlinear ...
An ab initio study based on local-density-functional (LDF) theory is presented for the chemisorption of hydrogen on the Pd(111) surface. Our calculation uses the Vienna ab initio molecular-dynamics program (VAMP) based on (i) finite-temperature LDF, (ii) exact calculation ...
Results from several commonly used approximate methods of evaluating electrostatic interactions have been compared to the rigorous, nonexpanded electrostatic energies at both uncorrelated and correlated levels of theory. We examined a number of energy profiles for both hydrogen bonded and stacked configurations of the nucleic acid base pairs. We found that the penetration ...
The low-temperature parts of phase diagrams for the quasibinary and quasiternary semiconductors of AIIIBV type in the Al/Ga/In/Sb system were calculated based on the ab initio calculations without employing any experimental information. Via global exploration of the enthalpy landscapes for many different compositions in these ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... of Molecular Modelling and Ab initio Molecular ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Development of Ab-initio Multibody ...
... Ab initio Energies Calculated Using 3 ... of the Transition States (TS ... Descriptors : *TRANSITIONS, *MOLECULES, COMPUTATIONS, COMPARISON ...
... Abstract : Results are presented from ab initio quantum chemical calculations on the ground state potential energy surface for the open shell ...
... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : An Ab Initio Study of Solid ...
... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : An AB Initio Study of Dimethyl ...
... Accession Number : ADA523968. Title : Ab-initio Simulations of Molten Ni Alloys. Descriptive Note : Journal article (preprint). ...
... We carried out ab-initio quantum chemical calculations on these energetic cyclic ethers and generated the electrostatic molecular potential contour ...
Ab initio quantum chemical techniques have been used to investigate weakly bund complexes of H20 and SO2. An energy gradient program was used to ...
... Accession Number : ADA351780. Title : Ab Initio and DFT Potential Energy Surfaces for Cyanuric Chloride Reactions. Descriptive Note : Final rept. ...
... Ab initio study on atomic structures and physical properties of CdSe quantum nanodots ... Figure 2. Diagram of covered nanodots. ...
... Title : Ab Initio Study on Atomic Structures and Physical Properties of CdSe Quantum Nanodots. Descriptive Note : Final rept. ...
... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : Ab Initio Study of the Structure ...
... Rydberg I 'Flu state. Demoulin and Jungen (1974) used an ab initio quantum chemical approach, but only at the SCF level ...
... moment has been cancelled a priori for the electronic transition as a function of R(CC), using ab initio quantum chemical techniques including state ...
... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : Ab Initio Study of Ultracold ...
1 AB INITIO STUDIES ON HEXAVALENT PHOSPHORUS COMPOUNDS Ashley L. Wilson* Aberdeen High School Aberdeen, Maryland 21001 ...
... Accession Number : ADA436055. Title : Ab Initio Studies on Hexavalent Phosphorus Compounds. Descriptive Note : Conference paper. ...
... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : Ab Initio Relativistic Study of ...
... Accession Number : ADA440631. Title : Ab Initio Quantum Chemical Study of Electron Transfer in Carboranes. Descriptive Note : Journal article. ...
... Accession Number : ADA270577. Title : Ab Initio Potential Energy Surface for the H + OCS Reaction. Descriptive Note : Final rept. ...
... [2"- ARMY RESEARCH LABORATORY [C Ab Initio Potential Energy Surface for H + OCS Reactions: Extended Basis Sets ...
... Ab initio direct trajectory simulation on hydrogen atom transfer in 7-azaindole in the electronic excited state with assist of water molecules ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab Initio Direct Trajectory Simulation on ...
... Title : Ab Initio Calculation of Vibrational Circular Dichroism Spectra Using Accurate Post-Self-Consistent-Field Force Fields: trans-2,3 ...
... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab Initio Calculation of Intermolecular ...
... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : AB Initio Propagator Theory of ...
... Using large scale O(N) real-space-based ab initio calculations, we carried ... and on "designing" new materials with enhanced piezoelectric response. ...
... The work presented here makes use of state-of- validated mathematical criteria for predicting the-art AIMD simulations as a means for testing the ...
We present a method for the computation of cohesive and structural properties of solids. The method is based on a local orbital description of the wavefunctions, an ab initio pseudopotential construction for the ion-core potential, and a local density tre...
Perturbative variational calculations of thermodynamic and structural properties of liquid metals, based on the use of ab initio and highly reliable nonlocal pseudopotentials for the electron-ion interactions and of the fluid of charged hard spheres as re...
Hydrozirconization of acetylene and ethylene was studied for Cp{sub 2}Zr(H)Cl. The study was based on ab initio MO theory calculations. Hydrozirconation by Cl{sub 3}ZrH was presented for comparison with the Cp analog.
Metal atom clusters are studied based on the application of ab initio quantum mechanical approaches. Because these large 'molecular' systems pose special practical computational problems in the application of the quantum mechanical methods, there is a spe...
My efforts in the Density Functional Theory (DFT) project of Dr. Bartlett's research group have been limited to the implementation of analytical energy gradients with respect to nuclear displacement in ACES2. The most immediate benefit of this work is ana...
Dynamics of the O( ) + HCl reaction on the electronic state: A new ab initio potential energy for the lowest electronic state of the O( ) + HCl system is presented. This surface is based on electronic the reactants O( ) + HCl() to the products OH() + Cl( ). The reaction barrier on this surface lies at an O
A method is presented for the ab initio calculation of configuration interaction in many-electron spectra. It is based on the expansion of the total electronic wavefunction in terms of Hartree-Fock-Slater determinants, as calculated by the programs of Her...
The work done in this paper is based on our earlier work on developing an extended Miedema model and then using it to downselect potential alloy systems. Our approach is to closely couple the semi-empirical methodologies to more accurate ab initio methods...
We discuss a recent investigation of adatom behavior on the AISb(001) surface using first-principles electronic structure methods based on the density functional theory. For Al and Sb adatoms, we find a number of novel adatom structures that differ dramat...
The transport properties of two ferrocenedithiolate systems with different five-member ring connections have been estimated using the nonequilibrium Green's function formalism of quantum transport and the density functional theory. The results of the calc...
An analysis of the vibrational spectra of the bent triatomic molecules HCO and DCO has been performed using algebraic methods. A model based on coupled U(2) algebras has been proposed for the description of the vibrational spectrum of HCO. The vibron model, based on the U(4) Lie algebras, has then been applied for the calculation of the vibrational spectra ...
The ab-initio calculations based on density functional theory (DFT) are performed for Fe and C in their ground state crystal structures. Heats of formation are then calculated for different Fe-C alloy compounds. The lattice constant (volume), bulk modulus and shear moduli for cementite are determined from the total energy calculations. These material ...
Self-assembled functional devices using hybrid inorganic/organic interfaces has been an area of recent interest in interdisciplinary science and engineering research. Chemical and biological systems using bottom-up approach hold promise to continue the scaling of nano devices. Our current research is focused on model studies involving chemical/biological self-assembly based on ...
We introduce an ab initio molecular-dynamics method based on the discretized path-integral representation of quantum particles. Fermi statistics is automatically generated by an effective exchange potential. This path-integral molecular-dynamics method is able to simulate electron plasmas at the border of the degenerate and the ...
We have developed an ab initio path integral molecular dynamics method based on the fragment molecular orbital method. This �FMO-PIMD� method can treat both nuclei and electrons quantum mechanically, and is useful to simulate large hydrogen-bonded systems with high accuracy. After a benchmark calculation for water monomer, water ...
We report full ab initio Hartree-Fock calculation to compute quantum mechanical interaction energies for ?-trypsin/benzamidine binding complex. In this study, the full quantum mechanical ab initio energy calculation for the entire protein complex with 3238 atoms is made possible by using a recently developed MFCC ...
Combined ab initio and micromagnetic simulations are carried out to build up a direct relationship between critical switching current Jc and geometric structure (in-plane lattice constant a and film thickness) of FePt in magnetic tunnel junctions. Ab initio calculations predict that the strain effect can ...
Recent progress in the ab-initio molecular dynamics method and the power of parallel computing, allow the detailed study of complex chemical reaction of great industrial relevance. We illustrate this unprecedented capability by investigating the second generation Ziegler-Natta catalytic process. In this inhomogeneous catalyst, a polymerization reaction is induced by TiCl4 ...
A model for the evolution of conduction and valence bands of IIIA-VA (InAs, GaAs, and InP) semiconductors under (001) biaxial strain is developed. The model is based on the ab initio calculations which take into account finite strain dependent relaxation of the reference levels. The results of ab ...
We build an "all-electron" norm-conserving pseudopotential for boron which extends the use of ab initio molecular dynamics simulations up to 50 times the normal density rho0. This allows us to perform ab initio simulations of dense plasmas from the regime where quantum mechanical effects are important to the regime ...
We build an 'all-electron' norm-conserving pseudopotential for boron which extends the use of ab initio molecular dynamics simulations up to 50 times the normal density {rho}{sub 0}. This allows us to perform ab initio simulations of dense plasmas from the regime where quantum mechanical effects ...
Ab initio calculations have been performed at the SCF level in the STO-3G, 3-21G, and 6-31G* basis sets on a variety of benzenoid and nonbenzenoid aromatic hydrocarbons, ranging from benzene to coronene. It is shown that (1) the enthalpy changes for homodesmic reactions involving only benzenoid aromatics can be computed accurately in all three ...
Point defects in Fe and dilute FeCu alloys are investigated by ab initio calculations based on density functional theory. The relaxed vacancy and interstitial and substitutional Cu atom formation energies are determined as well as some migration energies. The binding energies of various Cu containing defects believed to play an ...
The structural, electronic and dynamic properties of cesium chloride, ZrRu and ZrZn were studied by employing an ab initio pseudopotential method and a linear response scheme, within the generalized gradient approximation. The calculated lattice constant, bulk modulus and first-order pressure derivative of the bulk modulus were reported in B2 structure and ...
Structural and thermal properties of small lithium clusters are studied using ab initio-based Monte Carlo simulations. The ab initio scheme uses a Hartree-Fock/density functional treatment of the electronic structure combined with a jump-walking Monte Carlo sampling of nuclear configurations. Structural forms of ...
We outline two complementary approaches based on the no core shell model (NCSM) and present recent results. In the ab initio approach, nuclear properties are evaluated with two-nucleon (NN) and three-nucleon interactions (TNI) derived within effective field theory (EFT) based on chiral perturbation theory (ChPT). ...
We report on the determination of a high quality ab initiu potential energy surface (PES) and dipole
