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Electronic calculations

The relative intensity of a certain LEED diffraction spot is 0.25 at 300 K and 0.050 at 570 K using 390-eV electrons. Calculate the Debye temperature of the crystalline surface (in this case of Ru metal). [Pg.312]

The consistent total energy makes it possible to compute singlet-triplet gaps using RHF for the singlet and the half-electron calculation for the triplet. Koopman s theorem is not followed for half-electron calculations. Also, no spin densities can be obtained. The Mulliken population analysis is usually fairly reasonable. [Pg.230]

Relativistic density functional theory can be used for all electron calculations. Relativistic DFT can be formulated using the Pauli formula or the zero-order regular approximation (ZORA). ZORA calculations include only the zero-order term in a power series expansion of the Dirac equation. ZORA is generally regarded as the superior method. The Pauli method is known to be unreliable for very heavy elements, such as actinides. [Pg.263]

This formula is another variation on the Affinity Laws. Monsieur s Darcy and VVeisbach were hydraulic civil engineers in France in the mid 1850s (some 50 years before Mr. H VV). They based their formulas on friction losses of water moving in open canals. They applied other friction coefficients from some private experimentation, and developed their formulas for friction losses in closed aqueduct tubes. Through the years, their coefficients have evolved to incorporate the concepts of laminar and turbulent flow, variations in viscosity, temperature, and even piping with non uniform (rough) internal. surface finishes. With. so many variables and coefficients, the D/W formula only became practical and popular after the invention of the electronic calculator. The D/W forntula is extensive and eomplicated, compared to the empirieal estimations of Mr. H W. [Pg.99]

C. A. Coulson and A. Streitwieser, Jr., Dictionary of n-Electron Calculations, W. H. Freeman, San Francisco, 1965 E. Heilbronner and P. A. Straub, Hiickel Molecular Orbitals, Springer-Verlag, Berlin, 1966. [Pg.32]

Ab initio ECPs are derived from atomic all-electron calculations, and they are then used in valence-only molecular calculations where the atomic cores are chemically inactive. We start with the atomic HF equation for valence orbital Xi whose angular momentum quantum number is 1 ... [Pg.172]

The performance of VASP for alloys and compounds has been illustrated at three examples The calculation of the properties of cobalt dislicide demonstrates that even for a transition-metal compound perfect agreement with all-electron calculations may be achieved at much lower computational effort, and that elastic and dynamic properties may be predicted accurately even for metallic systems with rather long-range interactions. Applications to surface-problems have been described at the example of the. 3C-SiC(100) surface. Surface physics and catalysis will be a. particularly important field for the application of VASP, recent work extends to processes as complex as the adsorption of thiopene molecules on the surface of transition-metal sulfides[55]. Finally, the efficiciency of VASP for studying complex melts has been illustrate for crystalline and molten Zintl-phases of alkali-group V alloys. [Pg.80]

The button cells that provide the energy for watches, electronic calculators, hearing aids, and pacemakers are commonly alkaline systems of the silver oxide-zinc or mercuric oxide-zinc variety. These alkaline systems provide a vei y high energy density, approximately four times greater than that of the alkaline zinc-manganese dioxide battery. [Pg.121]

Calculations of life-cycle costs, net benefits, or other measures of economic performance are commonly performed on electronic calculators, commercial spreadsheet software, or by hand. The calculation approach for life-cycle costs is to first compute the net cost amount in each period for each alternative, C(t,x). The life-cycle cost (LCC) of each alternative is then calculated as the sum of the discounted values of C(t,x) over the entire planning horizon ... [Pg.217]

To properly handle the changing composition relationships it is almost essential to utilize some electronic computer techniques if good accuracy is to be achieved. Even three component systems become tedious using desk size electronic calculators without significant internal memory. Computers can be well programmed to handle the complexities of trial and check for convergence to a preset acceptable limit. [Pg.68]

The reason why we find it possible to construct, say, electronic calculators, and indeed why we can perform mental arilhinelie, cannot be found in mathematics or logic. The reason is that the laws of physics happen to permit the existence of physical models for the operations of arithmetic such as addition, subtraction and multiplication. If they did not, these familiar operations would be non-computablo functions. ... [Pg.682]

Unfortunately the complete calculation of the principal polarizabilities of a polyatomic molecule including the Silberstein interactions is very complex. Possibly electronic calculators will make this computation feasible for an array of molecules such as the... [Pg.80]

A negative BOP can usually be interpreted as a repulsive interaction in valence-only MO calculations in all-electron calculations, strongly antibonding core MOs are occupied, and negative BOPs are likely to occur even between strongly bound atoms. [Pg.15]

For the method for calculating these and similar results given in this chapter, see Higasi, K. Baba, H. Rembaum, A. Quantum Organic Chemistry Interscience NY, 1965. For values of calculated orbital energies and bond orders for many conjugated molecules, see Couison, C.A. Streitwieser Jr., A. Dictionary ofn Electron Calculations W.H. Freeman San Francisco, 1965. [Pg.79]

A more complete coverage of the literature on electronic spectra of radicals is presented in our paper submitted for publication in Fortschr. Chem. Forsch. (Topics in Current Chemistry), where theafi initio studies are also reviewed and the existing open-shell computational procedures discussed. Recently we performed semiempirical all-valence-electron calculations on ground-state properties and electronic spectra of small radicals (Zahradnik, R., and P. Carsky, Theoret, Chim. Acta, 27, 121 (1972) and Carsky, P., M. Machacek, and R. Zahradnik, Coll. Czech. Chem. Commun., in press) and on equilibrium constants of dimerization reactions of small radicals (Zahradnik, R., Z. Slanina, and P. (5arsky, to be published). [Pg.380]

Wanek, P. M., et al., Inaccuracies in the Calculation of Standard Deviation with Electronic Calculators, Anal. Chem. 54, 1982, 1877-1878. [Pg.406]

The quality of electronic calculations is confirmed by the very good agreement of the resonance energies for both a components if we compared to the experimental ones, as shown on table 3. [Pg.269]

The anharmonic modes for both the a symmetric and 67 asymmetric CH stretching vibrations have been explored. In order to perform a reasonable anharmonic treatment, we had to take into account the stretching of the bonds to larger elongations than for the harmonic description where displacements can be confined close to the equilibrium geometry. Consequently, correlation effects were included in the determination of the potential surface. The electronic calculations were carried out at the MP2 level, which insures a good description of the CH bond potential towards dissociation. A double zeta... [Pg.406]

The atomic weight of silver is 107.9 gmol and its density is 10.49 gcm . Assuming that each silver atom has one conduction electron, calculate... [Pg.231]


See other pages where Electronic calculations is mentioned: [Pg.108]    [Pg.2210]    [Pg.2214]    [Pg.2222]    [Pg.174]    [Pg.155]    [Pg.329]    [Pg.860]    [Pg.791]    [Pg.791]    [Pg.80]    [Pg.124]    [Pg.125]    [Pg.128]    [Pg.171]    [Pg.76]    [Pg.79]    [Pg.38]    [Pg.38]    [Pg.588]    [Pg.17]    [Pg.118]    [Pg.7]    [Pg.195]    [Pg.17]    [Pg.143]    [Pg.57]    [Pg.117]   
See also in sourсe #XX -- [ Pg.47 ]




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4.14. Calculated electronic structure

AIMD simulation method electronic structure calculations

Ab Initio Calculations of Electronic Absorption Spectra

Ab initio calculation of electronic

Ab initio calculations of electronic structure

Ab initio electronic energy calculation

Accurate Relativistic Fock-Space Calculations for Many-Electron Atoms

Active electrons, CASSCF/CASPT2 calculations

Alkali electron affinities, calculation

Antisymmetrized wave function, electronic structure calculations

Atomic orbitals electronic structure calculations

Basis Sets in the Electron-structure Calculations of Crystals

Beyond Molecular Electronic Calculations

Born-Oppenheimer approximation, electronic structure calculations

Calculated electron densities

Calculated electron densities components

Calculated electron-density map

Calculating electron conservation efficiencies for anaerobic growth processes

Calculation of electron affinities

Calculation of molecular electronic wave functions and energies

Calculation of the Electronic Factor

Calculations of electron-density maps

Calculations, band theory localized electron

Calculator, electronic

Carbon clusters electronic structure calculations

Catalysts, electronic structure calculations

Computational methods electronic structure calculations

Configuration-interaction methods electronic structure calculations

Coupled-cluster theory, electron correlation configuration interaction calculations

Density functional theory electronic structure calculations

Density functional theory-electron spin resonance calculations

Direct Calculation of Electronic Coupling

Doubly excited electron configuration calculation

Dyson orbitals electron propagator calculations

Electron Calculations and the Analysis of Experimental Data

Electron Correlation on Calculated Infrared Intensities

Electron affinity, calculation

Electron correlation calculations

Electron correlation calculations Pauli exclusion principle

Electron densities, calculation

Electron density distribution, calculations

Electron density distributions electrostatic potential calculations

Electron density, calculation by molecular

Electron distributions surface states calculation

Electron energy calculations, (

Electron irradiation, energy absorbed calculation

Electron pair-bond calculations

Electron pairs, calculation

Electron paramagnetic resonance calculation

Electron repulsion integrals rapid calculation

Electron spectroscopy calculations

Electron spin resonance hyperfine calculations

Electron transfer calculation progress

Electron transfer calculations

Electron transport system activity, calculating

Electron-correlated calculations, nuclear

Electron-correlated calculations, nuclear applications

Electron-correlated calculations, nuclear chemical shifts

Electron-correlated calculations, nuclear density functional theory

Electron-correlated calculations, nuclear independence

Electron-correlated calculations, nuclear magnetic resonance chemical

Electron-correlated calculations, nuclear shifts

Electron-correlated level calculations

Electron-structure calculations

Electronic Calculations on Large Molecules

Electronic Structure Calculations Algebraic Approach

Electronic Structure Calculations Numerical Approach

Electronic Structure Calculations Via Density Functional Theory

Electronic Structure of Naked, Ligated and Supported Transition Metal Clusters from First Principles Density Functional Calculations

Electronic Wavefunctions and Calculation of Matrix Elements

Electronic band structure calculations

Electronic calculations for molecules

Electronic calculator, significant digits

Electronic charge density calculation

Electronic charge distribution theoretical calculation

Electronic delay storage automatic calculator

Electronic excitation quantum chemical calculations

Electronic numerical integrator and calculator

Electronic numerical integrator and calculator ENIAC)

Electronic options calculating

Electronic self-consistent calculation

Electronic spectra approximate calculation

Electronic spectra calculated from Raman

Electronic spectra, calculations

Electronic states Self-consistent field calculations, electron

Electronic states calculations

Electronic structure calculations

Electronic structure calculations - the algebraic approach

Electronic structure calculations - the numerical approach

Electronic structure calculations geometric optimization

Electronic structure calculations thermodynamics

Electronic structure calculations transition state theory

Electronic structure calculations vertical ionization energy

Electronic structure calculations water bonds

Electronic structure calculations with Gaussian basis functions

Electronic structure calculations, changes

Electronic structure calculations, thiophene

Electronic structure electron correlation calculations

Electronic structure first-principle calculations

Electronic structure geometric calculations

Electronic structure minimum energy path calculations

Electronic structure perturbation theory calculations

Electronic structure wave-function calculations

Electronic transition, calculation

Electrons in Molecular Calculations

Energy band calculations itinerant electrons

Enthalpy predictions electronic structure calculations

Entropy electronic structure calculations, free energy

Free energy predictions electronic structure calculations

Gaussian basis sets electronic structure calculation. LCAO

Gaussian functions, electronic structure calculation

Gaussian wavepacket calculations electronic states

General Aspects of Quantum Chemistry and Electronic Structure Calculations

Geometric calculations transition metal electronic structure

H. Stoll, Electronic structure calculations for molecules containing lanthanide atoms

Hamiltonian operator electronic structure calculations

Hartree-Fock calculation electron density with

Hartree-Fock calculations electron correlation

Hydrogen bonds electronic structure calculations

Imidazoles, calculations electronic structure

Indolizine, calculated electron densities

Infrared spectroscopy electronic structure calculations

Interfacial electron transfer, calculated

Isotope effects electronic structure calculations

Kinetic isotope effects electronic structure calculations

Magnetic properties in DKH calculations of electronic g values

Many-electron local potential calculation

Many-electron wave functions, electronic structure calculations

Methods of electronic structure calculation

Methylene electronic structure calculations

Molecular orbital calculation-constrained electron diffraction

Molecular orbital calculations electronic structures

Molecular orbital calculations multiple electronic states

Molecules, small electron-correlated calculations

Multi-electron calculations

Nuclear magnetic resonance chemical shifts, electron-correlated calculations

Nuclear-electron attraction, electronic structure calculations

One-electron calculation

Organic molecules electron-correlated calculations

Palladium, electronic structure calculation

Pauli exclusion principle, electronic structure calculations

Periodic calculations electronic structure

Post-HF calculations electron correlation

Post-Hartree-Fock Calculations Electron Correlation

Proton Insertion in Polycrystalline WO3 Studied with Electron Spectroscopy and Semi-empirical Calculations

Pyrrole electronic structure calculations

Qualitative models, electronic structure calculations

Quantum Chemical Calculations of Electronic Excitation

Quantum mechanical calculations electronic structure

Quantum mechanical calculations of electron

Reaction mechanisms electron correlation calculations

Reaction mechanisms electronic structure calculations

Relativistic Pseudopotential Calculations for Electronic Excited States

Schrodinger equation electronic structure calculations

Scientific notation electronic calculators

Self-consistency Hartree-Fock electronic structure calculations

Self-consistent field theory Hartree-Fock electronic structure calculations

Semiempirical methods of electronic structure calculation

Significant figures electronic calculators and

Size-consistent calculations, electron correlation

Size-consistent calculations, electron correlation configuration interaction

Spectra calculations electronic circular dichroism

Spin-polarized electronic structure calculation

Stationary points, electronic structure calculations

Stokes shift calculations, electron-transfer

Structure, electronic, atmospheric systems calculations

The Electron Balance and Equilibrium Calculations

The estimation of net atomic charges from calculated electron densities

Theoretical Calculations of Electronic Spectra

Theoretical calculations electronic structure

Theory Periodic Electronic Structure Calculations

Total electron count, calculation

Transition intensities electronic structure calculations

Two-electron integral calculations

Wavefunction-based electron correlation calculations

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