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Showing 1 to 20 of 44 for “"ground state energy"”.
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A calculation of the ground-state energy of liquid Helium II
A variational energy calculation for an N-particle boson system has been performed. A two-body Hamiltonian, containing the phenomenological Lennard-Jones 6-10 potential, has been assumed, and the parameters of the Lennard-Jones potential have been chosen appropriate for liquid helium II. The trial …
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Investigation into the properties and application of the Diffusion Monte Carlo method
… will prove to be adept in producing the ground state energy and ground state wave function for systems governed by the Schrodinger equation. In this paper, familiar problems like the ground state energy of the harmonic oscillator and the Morse oscillator shall be solved using the DMC …
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The diagramatical solution of the two-impurity Kondo problem
… regimes. The integral equations for the ground state energy are established and solved numerically. The two-stage Kondo effect and corresponding energy scales are found which agree with the scaling results.
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Investigation of Host-Sensitized Luminescence of Trivalent Lanthanide Doped Yttrium Phosphate using VUV Spectroscopy
… intense 150 nm excitation intensity and the ground state energy level of select trivalent lanthanide elements was proposed. Using spectroscopy, the host-to-activator transfer efficiencies of YPO<sub>4</sub>:Ln<sup>3+ </sup>(Ln<sup>3+</sup> = Sm<sup>3+</sup>, Eu<sup>3+</sup> and …
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Dissipative Quantum Systems and Flow Equations
… bosonic mode. The Flow Equation results for the ground-state energy and for the transformation of the Pauli spin matrices are compared with the numerically exact solution. For the Spin-Boson Model with an arbitrary number of bosonic modes and explicitly broken reflection symmetry, general Flow …
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The ground state of liquid helium-four
The properties of the ground state of liquid He-4 are studied using a variational wave function of the form TT f(rij)o The Lennard-Jones 12-6 potential with i<j parameters determined from the gas data by de Boer and Michels is used o The configuration space integrals are performed by the Monte …
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Exact and variational investigations of Hubbard rings
… techniques to obtain a lower bound for the ground state energy. From the Lieb-Wu equations we derive an exact expression for the ground state energy in the atomic limit. We obtain our result by exploiting the spin symmetry of the Hubbard Hamiltonian. Our energy is lower than that obtained by …
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The weakly coupled polaron
… the phonon-cross-exchange diagrams in the self-energy, a vertex correction has been made to the lowest order diagram. The real part and the imaginary part of the self-energy are obtained. The dispersion relationship obtained by this approximation gives the ground state energy which is lower than …
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Density functional theory study of the conductivity of the biphenalenyl radical dimer
… neurtral radical in its singlet and triplet states. We performed calculations on the dimer to study its conductivity by investigating the ground state energy, HOMO-LUMO gap, charge localization, and reorganization energies, as these are the main contributing factors to crystal conduction. We …
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The one-dimensional spin-1/2 ANNNI model in non-commuting magnetic fields
… by an investigation of the zero temperature ground state of the one-dimensional spin-1/2 ANNNI model in a longitudinal magnetic field. By using the symmetries of the Hamiltonian, we were able to diagonalize the longitudinal ANNNI model exactly. We found that there are four different possible …
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Bazinių mašininio mokymo modelių taikymas kvantinės chemijos duomenų analizei /
… specifically focusing on predicting molecular energy states accurately without sacrificing computational efficiency. The main problem addressed by this research is the accurate determination of a molecule's ground state energy from its Cartesian coordinates, a task complicated by the need for …
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An evaluation of the performance of the quantum adiabatic algorithm on random instances of k-SAT
… dependent Hamiltonian that is placed into its ground state will remain in its ground state provided that the Hamiltonian of the system varies slowly enough with time. This work investigates the performance of the quantum adiabatic algorithm on random instances of k-SAT. The performance of the …
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Development of multicomponent coupled-cluster theory and its application to nanoclusters and molecular systems
… method was then used to study excited electronic states in molecular systems and semiconductor quantum dots via the electron-hole representation. It was also used to calculated ground state energy of the positronium hydride system. These projects sparked further interest in the con- sequences of …
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Towards Systematic Improvement of Density Functional Approximations
… theory is a formally exact theory to describe ground state properties due to the existence of the exact functional. In practice, the usefulness of density functional theory relies on the accuracy of density functional approximations. After decades of effort of functional developments, the …
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Charge Transfer at Thin-Film Modified Solid -Liquid Interfaces in the Absence of Redox-Active Moieties
… mechanical tunneling of the electron from the ground-state energy level of the electrolytic ionic species to the electrode Fermi level becomes rate-limiting. On the other hand, for cathodic potentials, the charge flux is limited by the thermal activation of either the transferring electron or …
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Variational theory of quantum fluids
… operator that approximately transforms the states of a non-interacting system into the corresponding states of the interacting-system. The theory can be regarded as a microscopic realization of Landau's assumption of a one-to-one correspondence between the non-interacting and interacting …
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The study of many-electron systems
… Without much computational effort, the ground state energy is well approximated, especially in strong-coupling limit. Some electronic properties are examined using the variational ground state wavefunction. The one-dimensional Hubbard model has been solved exactly for small-size clusters …
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Theoretical and Computational Aspects of the Optimized Effective Potential Approach within Density Functional Theory
… approximations to the exchange-correlation energy functional. Use of functional approximations depending explicitly upon the density alone appear unable to address all aspects of many-body interactions, such as the fundamental constraint that the ground state energy is a piecewise linear …
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Contributions to Information-Based Complexity and to Quantum Computing
… quantum algorithms for the estimation of the ground state energy of the multivariate time-independent Schrodinger equation corresponding to a multiparticle system in a box. The dimension d of the problem depends linearly to the number of particles of the system. We design a quantum algorithm …
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Variable Energy Photoelectron Spectra Of Organometallic Compounds Of The Late Transition Metals
… spectroscopy (PES) studies with variable photon energy for organometallic molecules of late transition metals, including cobalt, rhodium, iridium, nickel, palladium, platinum, copper, and silver. Synchrotron radiation (in the range of 30 to 170 eV photon energy) and traditional helium I (21.22 …
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