Zobrazeno 1 - 10
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pro vyhledávání: '"William A. Lester"'
Autor:
Vladimir Z. Kresin, William A. Lester
Publikováno v:
International Journal of Quantum Chemistry. 36:17-26
A new version of adiabatic theory enabling one to evaluate higher-order nonadiabatic terms has been developed. One introduces a nonadiabatic Hamiltonian Ĥna so that the total Hamiltonian is given by Ĥ = Ĥ0 + Ĥna, where Ĥ0 describes the nonintera
Autor:
Vladimir Z. Kresin, William A. Lester
Publikováno v:
International Journal of Quantum Chemistry. 20:703-714
An adiabatic theory of polyatomic photodissociation is developed that explicitly treats the interaction between the relative and internal motion and leads to an expression for the nuclear wavefunction of the final dissociative state which differs con
Publikováno v:
The Journal of Physical Chemistry A. 112:2082-2087
Heats of formation of the lowest triplet state of ethylene and the ground triplet state of ethylidene have been predicted by high level electronic structure calculations. Total atomization energies obtained from coupled-cluster CCSD(T) energies extra
Publikováno v:
The Journal of Chemical Physics. 119:1483-1488
A theoretical study is reported of the transition between the ground state ({sup 1}A{sub g}) and the lowest triplet state (1{sup 3}B{sub 1u}) of ethylene based on the diffusion Monte Carlo (DMC) variant of the quantum Monte Carlo method. Using DMC tr
Autor:
William A. Lester, Joachim Schaefer
Publikováno v:
The Journal of Chemical Physics. 59:3676-3686
Integral cross sections for rotational excitation of H2 by Li+ impact have been computed in a coupled channel formalism for the energy range 0.05–0.5 eV. Computational results are reported for the rigid rotator, ``energy corrected'' rigid rotator,
Autor:
William A. Lester, Vladimir Z. Kresin
Publikováno v:
The Journal of Physical Chemistry. 86:2182-2187
An adiabatic method for the evaluation of the nuclear wave function describing the final dissociative state and a rigorous description of the D state following adiabatic formulation are presented in this paper. The vibrational frequencies of the frag
Publikováno v:
International Journal of Quantum Chemistry. 26:691-700
In this theory a chemical reaction is treated as a quantum transition from reactants to products. The approach leads to a Franck–Condon-like factor for the evaluation of product energy distributions. Second-quantization representation is used to en
Publikováno v:
The Journal of Chemical Physics. 86:2639-2652
Polyatomic indirect photodissociation is treated as a quantum transition between quasidiscrete and dissociative (photofragment) states. Our adiabatic method is followed to describe the nuclear dynamics of the dissociative state. Ab initio MCHF excite
Autor:
Vladimir Z. Kresin, William A. Lester
Publikováno v:
Chemical Physics. 90:335-346
A new approach for the evaluation of product energy distributions of chemical reactions is presented. The approach is characterized by two main features. The first is the introduction of a specific reaction hamiltonian (in second quantization formali
Autor:
Frank Rebentrost, William A. Lester
Publikováno v:
The Journal of Chemical Physics. 64:3879-3884
The matrix elements necessary for the description of electronic interactions between the 1 2A′, 2 2A′, and 2A″ surfaces of FH2 are evaluated from Born–Oppenheimer states. It is shown that these couplings are handled most appropiately in a dia