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1
Pubs.GISS: Green and Zare 1977: Ab initio calculation of the spin ...

Ab initio calculations are carried out to determine ?? (true), the first-order contribution to the spin-rotation constant, ??, for the X2? ground states of ...

NASA Website

2
Additivity of Cation- Interactions: An ab Initio Computational Study on -Cation Sandwich Complexes

Additivity of Cation- Interactions: An ab Initio Computational Study on -Cation- Sandwich Complexes- sandwiches are the sums of the two corresponding TMA- systems. The contribution of electron correlation- sandwiches and to estimate their binding energies. Morokuma decomposition analysis on the binding energy

E-print Network

3
Torsional anharmonicity in the conformational thermodynamics of flexible molecules
2005-01-01

We present an algorithm for calculating the conformational thermodynamics of large, flexible molecules that combines ab initio electronic structure theory calculations with a torsional path integral Monte Carlo (TPIMC) simulation. The new algorithm overcomes the previous limitations of the TPIMC method by including the thermodynamic ...

NASA Astrophysics Data System (ADS)

4
Toward an Understanding of the Spectral Tuning in Rhodopsin
2007-12-01

The contribution to the spectral tuning of the main residues in the Rhodopsine protein is being evaluated by employing high level ab initio quantum chemistry tools and the new Reverse Finger Print (RFP) technique.

NASA Astrophysics Data System (ADS)

5
Quantum Chemical Investigations of the Mechanism of ...
1983-10-28

... This study involves: Ab-initio crystal orbitals and polymer orbitals; Ab-initio coupled cluster program; Ab-initio quantum chemical calculations and ...

DTIC Science & Technology

6
Lithium cluster anions: photoelectron spectroscopy and ab initio calculations.
2011-01-28

Structural and energetic properties of small, deceptively simple anionic clusters of lithium, Li(n)(-), n = 3-7, were determined using a combination of anion photoelectron spectroscopy and ab initio calculations. The most stable isomers of each of these anions, the ones most likely to contribute to the photoelectron spectra, were found ...

PubMed

7
Lithium cluster anions: Photoelectron spectroscopy and ab initio calculations
2011-01-01

Structural and energetic properties of small, deceptively simple anionic clusters of lithium, Lin-, n = 3-7, were determined using a combination of anion photoelectron spectroscopy and ab initio calculations. The most stable isomers of each of these anions, the ones most likely to contribute to the photoelectron spectra, were found ...

NASA Astrophysics Data System (ADS)

8
Chalcopyrite Magnetic Semiconductors: An Ab-Initio Study of ...
2001-04-01

... Title : Chalcopyrite Magnetic Semiconductors: An Ab-Initio Study of Their Structural, Electronic and Magnetic Properties. ...

DTIC Science & Technology

9
COMPENDIUM OF AB INITIO CALCULATIONS OF ...
1967-12-01

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... COMPENDIUM OF AB INITIO CALCULATIONS ...

DTIC Science & Technology

10
An Ab Initio Study of the Geometry and Rotational Barrier of 4 ...
1990-03-16

... Accession Number : ADA219907. Title : An Ab Initio Study of the Geometry and Rotational Barrier of 4- Phenylimidazole. ...

DTIC Science & Technology

11
Ab Initio Calculations of the Magnetic Anisotropy.
1987-05-01

... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : Ab Initio Calculations of the ...

DTIC Science & Technology

12
Ab Initio Calculation of Vibrational Absorption and Circular ...
1995-02-01

... Title : Ab Initio Calculation of Vibrational Absorption and Circular Dichroism Spectra Using Density Functional Force Fields. ...

DTIC Science & Technology

13
AB Initio Quantum Chemical Investigations of Solubilities in ...
1992-11-17

... Title : AB Initio Quantum Chemical Investigations of Solubilities in Supercritical Solutions. Descriptive Note : Conference Paper,. ...

DTIC Science & Technology

14
Ab initio two-body potentials and the properties of condensed phases of helium atoms
2005-06-01

A careful comparison of some properties of systems of helium atoms in the liquid and solid phases is performed for several ab initio two-body potentials from the literature. Additional contributions from a three-body potential are considered as well. The multiweight diffusion Monte Carlo method is employed to quantitatively compute the ...

Energy Citations Database

15
Ab initio and Gordon--Kim intermolecular potentials for two nitrogen molecules
1980-07-01

Both ab initio MO--LCAO--SCF and the electron-gas (or Gordon--Kim) methods have been used to compute the intermolecular potential (Phi) of N/sub 2/ molecules for seven different N/sub 2/--N/sub 2/ orientations. The ab initio calculations were carried out using a (4s3p) contracted Gaussian basis set with and without ...

Energy Citations Database

16
AB Initio Study of the Electronic Magnetic Circular Dichroism ...
1991-01-15

... Title : AB Initio Study of the Electronic Magnetic Circular Dichroism ... functions are determined using as initio quantum chemical techniques including ...

DTIC Science & Technology

17
Molecular Spectroscopy by Ab Initio Methods
1994-01-01

Due to recent advances in methods and computers, the accuracy of ab calculations has reached a point

NASA Technical Reports Server (NTRS)

18
Localized Hole Effects in Inner-Shell Excitation.
1983-01-01

Ab initio calculations of valence shell ionization potentials have shown that orbital relaxation and correlation differences usually make contributions of comparable magnitude. In marked contrast to this observation is the situation for deep core ionizati...

National Technical Information Service (NTIS)

19
Covalent and Ionic Contributions to the Bonding of Atomic and Molecular Adsorbates on Metal Surfaces: A Cluster Model Approach.
1990-01-01

The molecular cluster model approach for the description of processes at surface is presented. It involves using finite clusters which contain surface atoms interacting with atomic or molecular adsorbates. Accurate ab initio wavefunctions can be obtained ...

National Technical Information Service (NTIS)

20
AB INITIO CALCULATIONS AND INTERNAL ROTOR: CONTRIBUTION FOR THERMODYNAMICS PROPERTIES SO298 AND CP(T) (300

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

EPA Science Inventory

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21
Ab initio calculation of the thermodynamic properties and atomic temperature factors of SiO2 ?-quartz and stishovite
1995-04-01

The constant-volume specific heat, the entropy, the phonon contributions to internal energy and Helmholtz free energy, and the atomic temperature factors of ?-quartz and stishovite, two allotropic forms of SiO2, are calculated as a function of temperature from ab initio phonon band structures. Available experimental data agree with our ...

NASA Astrophysics Data System (ADS)

22
Comparing ab initio density-functional and wave function theories: The impact of correlation on the electronic density and the role of the correlation potential.
2011-09-21

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 (2005)]. Recently, ...

PubMed

23
No-Core Shell Model and Reactions
2005-10-14

There has been a significant progress in ab initio approaches to the structure of light nuclei. Starting from realistic two- and three-nucleon interactions the ab initio no-core shell model (NCSM) can predict low-lying levels in p-shell nuclei. It is a challenging task to extend ab ...

Energy Citations Database

24
No-Core Shell Model and Reactions
2005-04-29

There has been a significant progress in ab initio approaches to the structure of light nuclei. Starting from realistic two- and three-nucleon interactions the ab initio no-core shell model (NCSM) can predict low-lying levels in p-shell nuclei. It is a challenging task to extend ab ...

DOE Information Bridge

25
Heteroaromatic Chromophores: Structure, Electric Properties, Condensed Phase and Aggregation Effects: a Combined Experimental and Theoretical Study
2007-12-01

We present a combined computational and experimental study on structural and electric properties of recently synthesized heteroaromatic dyes and their simple aggregates. Ab initio and density functional theory calculations are carried out to investigate ground state and excited state properties along with their modulation induced by the solvent described ...

NASA Astrophysics Data System (ADS)

26
Frequency shift of the cesium clock transition due to blackbody radiation.
2006-07-27

We perform ab initio calculations of the frequency shift induced by a static electric field on the cesium clock hyperfine transition. The calculations are used to find the frequency shifts due to blackbody radiation. Our result [deltanu/E2=-2.26(2)x10(-10) Hz/(V/m)2] is in good agreement with early measurements and ab ...

PubMed

27
Frequency Shift of the Cesium Clock Transition due to Blackbody Radiation
2006-07-28

We perform ab initio calculations of the frequency shift induced by a static electric field on the cesium clock hyperfine transition. The calculations are used to find the frequency shifts due to blackbody radiation. Our result [{delta}{nu}/E{sup 2}=-2.26(2)x10{sup -10} Hz/(V/m){sup 2}] is in good agreement with early measurements and ...

Energy Citations Database

28
Decomposing total IR spectra of aqueous systems into solute and solvent contributions: A computational approach using maximally localized Wannier orbitals
2005-06-01

The theoretical principles underpinning the calculation of infrared spectra for condensed-phase systems in the context of ab initio molecular dynamics have been recently developed in literature. At present, most ab initio molecular dynamics calculations are restricted to relatively small systems and short ...

NASA Astrophysics Data System (ADS)

29
Ab-Initio Simulation of a/2110> Screw Dislocations Gamma ...
2004-11-01

... AB-INITIO SIMULATION OF a/2110> ... 4. TITLE AND SUBTITLE AB-INITIO SIMULATION OF a/2110> SCREW DISLOCATIONS γ-TiAl 5c. ...

DTIC Science & Technology

30
Ab Initio Study on Spin Polarization of III-V Compound Tips
1998-06-01

... ADP012740 TITLE: Ab Initio Study on Spin Polarization of III-V Compound Tips ... Ab initio study on spin polarization of III-V compound tips ...

DTIC Science & Technology

31
AB Initio and Calphad Thermodynamics of Materials.
2004-01-01

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...

National Technical Information Service (NTIS)

32
40 CFR 86.004-30 - Certification.
2009-07-01

...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

33
Use of ab initio quantum mechanics calculations in group contribution methods. 1; Theory and the basis for group identifications
1991-05-01

Group contribution methods are powerful tools for estimating the thermophysical and thermodynamic properties of pure components and mixtures from experimental data on related substances. Among the problems with current group contribution methods is that there is no theoretical basis for defining functional groups and no a priori way of determining when a ...

Energy Citations Database

34
The Ab Initio No-core Shell Model
2009-05-01

This contribution reviews a number of applications of the ab initio no-core shell model (NCSM) within nuclear physics and beyond. We will highlight a nuclear-structure study of the A = 12 isobar using a chiral NN + 3NF interaction. In the spirit of this workshop we will also mention the new development of the NCSM formalism to describe ...

NASA Astrophysics Data System (ADS)

35
Potential energy surfaces for fluorine--hydrogen systems
1978-01-01

Ab initio molecular electronic structure theory has now progressed to the point where it is capable of making genuine contributions to the understanding of simple chemical reactions. Especially noteworthy examples are the elementary fluorine hydrogen reactions pertinent to the HF chemical laser. The reactions F + H/sub 2/ ..-->.. FH ...

Energy Citations Database

36
Phonon dispersion relations of zinc oxide: Inelastic neutron scattering and ab initio calculations
2010-05-01

Zinc oxide is a key material for optoelectronic applications, whose transport properties are typically dominated by the lattice vibrations. We report here the phonon-dispersion relations of wurtzite ZnO at 10 K, as determined by using inelastic neutron scattering. The experimental data are analyzed with the aid of ab initio calculations based on ...

NASA Astrophysics Data System (ADS)

37
Exploring Transition Metal Catalyzed Reactions via AB Initio Reaction Pathways
2011-06-01

The study and prediction of chemical reactivity is one of the most influential contributions of quantum chemistry. A central concept in the theoretical treatment of chemical reactions is the reaction pathway, which can be quite difficult to integrate accurately and efficiently. This talk will outline our developments in the integration of these pathways on ...

NASA Astrophysics Data System (ADS)

38
Ab initio simulation of the spin transition during chemisorption: H/Al(111).
2006-11-20

Electronically nonadiabatic effects during the chemisorption of hydrogen atoms on an Al(111) surface are simulated ab initio using time-dependent density-functional theory for the electrons in combination with Ehrenfest dynamics for the nuclei. Strongly nonadiabatic effects close to the spin transition of the H atom are identified, and the dissipated ...

PubMed

39
Static Pockels constants pij and pijk of CaF2 and BaF2 under strain from ab initio calculations
2007-11-01

Ab initio results for the static (linear) elasto-optic or Pockels constants pij and (nonlinear) constants pijk for the fluorite systems CaF2 and BaF2 are presented from investigating the dielectric tensor under various forms and sizes of strain. The contribution to the Pockels constant p44 from the internal strain is important ...

NASA Astrophysics Data System (ADS)

40
High-pressure ion-thermal properties of metals from ab initio interatomic potentials
1985-06-01

It has recently become possible for the first time to calculate ab initio two-ion and three-ion interatomic potentials in d-electron transition metals. The nature of these potentials for the 3d series metals is discussed. In the case of copper, where three-ion contributions may be neglected, application is made to the ion-thermal ...

Energy Citations Database

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41
Ab initio study of the effects of thin CsI coatings on the work function of graphite cathodes
2007-10-01

Cesium-iodide (CsI)-coated graphite cathodes are promising electron sources for high power microwave generators, but the mechanism driving the improved emission is not well understood. Therefore, an ab initio modeling investigation on the effects of thin CsI coatings on graphite has been carried out. It is demonstrated that the CsI coatings reduce the work ...

NASA Astrophysics Data System (ADS)

42
Representation of Zn(II) complexes in polarizable molecular mechanics. Further refinements of the electrostatic and short-range contributions. Comparisons with parallel ab initio computations.
2005-08-01

We present refinements of the SIBFA molecular mechanics procedure to represent the intermolecular interaction energies of Zn(II). The two first-order contributions, electrostatic (E(MTP)), and short-range repulsion (E(rep)), are refined following the recent developments due to Piquemal et al. (Piquemal et al. J Phys Chem A 2003, 107, 9800; and Piquemal et al., submitted). ...

PubMed

43
ab-Initio Molecular Dynamics Simulations of Molten Ni-Based ...
2007-06-01

... ADP023770. Title : ab-Initio Molecular Dynamics Simulations of Molten Ni-Based Superalloys. Descriptive Note : Conference paper. ...

DTIC Science & Technology

44
Overview of Molecular Modelling and Ab initio Molecular ...
2000-09-01

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... of Molecular Modelling and Ab initio Molecular ...

DTIC Science & Technology

45
New AB Initio Based Density Functional Methods for ...
2000-05-31

... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : New AB Initio Based Density ...

DTIC Science & Technology

46
Development of Ab-initio Multibody Energy Expansions for the ...
2010-10-31

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Development of Ab-initio Multibody ...

DTIC Science & Technology

47
Comparison of Single Point Ab initio Energies Calculated ...
1989-04-01

... Ab initio Energies Calculated Using 3 ... of the Transition States (TS ... Descriptors : *TRANSITIONS, *MOLECULES, COMPUTATIONS, COMPARISON ...

DTIC Science & Technology

48
An ab initio QCISD Study of the Potential Energy Surface for ...
1998-09-01

... Abstract : Results are presented from ab initio quantum chemical calculations on the ground state potential energy surface for the open shell ...

DTIC Science & Technology

49
An Ab Initio Study of Solid Nitromethane, HMX, RDX, and ...
2004-12-01

... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : An Ab Initio Study of Solid ...

DTIC Science & Technology

50
An AB Initio Study of Dimethyl Nitramine.
1987-08-01

... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : An AB Initio Study of Dimethyl ...

DTIC Science & Technology

51
Ab-initio Simulations of Molten Ni Alloys
2010-04-01

... Accession Number : ADA523968. Title : Ab-initio Simulations of Molten Ni Alloys. Descriptive Note : Journal article (preprint). ...

DTIC Science & Technology

52
Ab-Initio Molecular Dynamics Simulations of Molten Ni-Based ...
2007-06-01

... Title : Ab-Initio Molecular Dynamics Simulations of Molten Ni-Based Superalloys. Descriptive Note : Conference paper (preprint). ...

DTIC Science & Technology

53
Ab-Initio Molecular Dynamics Simulations of Molten Ni-Based ...
2008-07-01

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab-Initio Molecular Dynamics Simulations ...

DTIC Science & Technology

54
Ab-Initio MODPOT/VRDDO/MERGE Calculations on Energetic ...
1981-10-15

... We carried out ab-initio quantum chemical calculations on these energetic cyclic ethers and generated the electrostatic molecular potential contour ...

DTIC Science & Technology

55
Ab initio quantum chemical techniques have been used to ...

Ab initio quantum chemical techniques have been used to investigate weakly bund complexes of H20 and SO2. An energy gradient program was used to ...

NASA Website

56
Ab Initio and DFT Potential Energy Surfaces for Cyanuric ...
1998-07-01

... Accession Number : ADA351780. Title : Ab Initio and DFT Potential Energy Surfaces for Cyanuric Chloride Reactions. Descriptive Note : Final rept. ...

DTIC Science & Technology

57
Ab Initio Study on Atomic Structures and Physical Properties of ...
2009-11-25

... Ab initio study on atomic structures and physical properties of CdSe quantum nanodots ... Figure 2. Diagram of covered nanodots. ...

DTIC Science & Technology

58
Ab Initio Study on Atomic Structures and Physical Properties of ...
2009-11-25

... Title : Ab Initio Study on Atomic Structures and Physical Properties of CdSe Quantum Nanodots. Descriptive Note : Final rept. ...

DTIC Science & Technology

59
Ab Initio Study of the Structure, Vibrational Frequencies and ...
1995-06-01

... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : Ab Initio Study of the Structure ...

DTIC Science & Technology

60
Ab Initio Study of the Electric Dipole Transition Moment for the ...
1990-12-01

... Rydberg I 'Flu state. Demoulin and Jungen (1974) used an ab initio quantum chemical approach, but only at the SCF level ...

DTIC Science & Technology

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61
Ab Initio Study of the Electric Dipole Transition Moment for the ...
1990-12-01

... moment has been cancelled a priori for the electronic transition as a function of R(CC), using ab initio quantum chemical techniques including state ...

DTIC Science & Technology

62
Ab Initio Study of Ultracold Polar Molecules in Optical Lattices

... from federally funded research, testing and training ... and agencies for Research Development Test and Evaluation ... Title : Ab Initio Study of Ultracold ...

DTIC Science & Technology

63
Ab Initio Studies on Hexavalent Phosphorus Compounds
2002-01-01

1 AB INITIO STUDIES ON HEXAVALENT PHOSPHORUS COMPOUNDS Ashley L. Wilson* Aberdeen High School Aberdeen, Maryland 21001 ...

DTIC Science & Technology

64
Ab Initio Studies on Hexavalent Phosphorus Compounds
2002-01-01

... Accession Number : ADA436055. Title : Ab Initio Studies on Hexavalent Phosphorus Compounds. Descriptive Note : Conference paper. ...

DTIC Science & Technology

65
Ab Initio Relativistic Study of Formation of Ultracold Polar ...
2006-01-31

... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : Ab Initio Relativistic Study of ...

DTIC Science & Technology

66
Ab Initio Quantum Chemical Study of Electron Transfer in ...

... Accession Number : ADA440631. Title : Ab Initio Quantum Chemical Study of Electron Transfer in Carboranes. Descriptive Note : Journal article. ...

DTIC Science & Technology

67
Ab Initio Potential Energy Surface for the H + OCS Reaction
1993-10-01

... Accession Number : ADA270577. Title : Ab Initio Potential Energy Surface for the H + OCS Reaction. Descriptive Note : Final rept. ...

DTIC Science & Technology

68
Ab Initio Potential Energy Surface for H + OCS Reactions ...
1994-11-01

... [2"- ARMY RESEARCH LABORATORY [C Ab Initio Potential Energy Surface for H + OCS Reactions: Extended Basis Sets ...

DTIC Science & Technology

69
Ab Initio Potential Energy Surface for H + OCS Reactions ...
1994-11-01

... 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. ...

DTIC Science & Technology

70
Ab Initio Direct Trajectory Simulation on Hydrogen Atom ...
2006-07-14

... Ab initio direct trajectory simulation on hydrogen atom transfer in 7-azaindole in the electronic excited state with assist of water molecules ...

DTIC Science & Technology

71
Ab Initio Direct Trajectory Simulation on Hydrogen Atom ...
2006-07-14

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab Initio Direct Trajectory Simulation on ...

DTIC Science & Technology

72
Ab Initio Calculation of Vibrational Circular Dichroism Spectra ...
1996-02-01

... Title : Ab Initio Calculation of Vibrational Circular Dichroism Spectra Using Accurate Post-Self-Consistent-Field Force Fields: trans-2,3 ...

DTIC Science & Technology

73
Ab Initio Calculation of Intermolecular Potential Parameters for ...
2000-08-01

... from federally funded research, testing and training ... for Research Development Test and Evaluation ... Title : Ab Initio Calculation of Intermolecular ...

DTIC Science & Technology

74
AB Initio Propagator Theory of Clusters
2003-02-12

... from federally funded research, testing and training ... agencies for Research Development Test and Evaluation ... Title : AB Initio Propagator Theory of ...

DTIC Science & Technology

75
Exploring the ab initio/classical free energy perturbation method: The hydration free energy of water
2000-08-15

The ab initio/classical free energy perturbation (ABC-FEP) method proposed previously by Wood et al. [J. Chem. Phys. 110, 1329 (1999)] uses classical simulations to calculate solvation free energies within an empirical potential model, then applies free energy perturbation theory to determine the effect of changing the empirical solute-solvent interactions ...

Energy Citations Database

76
Three-body effects in hydrogen fluoride: survey of potential energy surfaces
2006-01-01

The potential energy surface for trimers of hydrogen fluoride is examined for multiple arrangements of the three-molecule cluster. Several established approaches to model the potential energy are examined, including a strictly pairwise additive potential, an established polarizable potential model, another, strictly three-body polarizable model, and a three-body potential recently fitted to ...

NASA Astrophysics Data System (ADS)

77
The chiral molecule CHClFI: first determination of its molecular parameters by Fourier transform microwave and millimeter-wave spectroscopies supplemented by ab initio calculations.
2005-06-30

The rotational spectrum of chlorofluoroiodomethane (CHClFI) has been investigated. Because its rotational spectrum is extremely crowded, extensive ab initio calculations were first performed in order to predict the molecular parameters. The low J transitions were measured using a pulsed-molecular-beam Fourier transform spectrometer, and the millimeter-wave ...

PubMed

78
Ab Initio Calculations of Water Line Strengths
1998-01-01

We report on the determination of a high quality ab initiu potential energy surface (PES) and dipole

NASA Technical Reports Server (NTRS)

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