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Schrbdinger equations, model electronic

The energies and wavefunctions of holes and electrons of these "W" and "M" QW cell were calculated by solving the Schrbdinger equation within the envelope function approximation in the framework of a 10-bands k p model including strain effects on the valence and conduction bands and the bandanticrossing (BAG) approach [4]. Further details in modeling are described elsewhere [5,6]. As shown in Fig. 1, an emission at 3.3 pm at RT with a carrier wavefunction overlap as high as 71% and 78% at equilibrium are predicted in... [Pg.598]

Two broad classes of technique are available for modeling matter at the atomic level. The first avoids the explicit solution of the Schrbdinger equation by using interatomic potentials (IP), which express the energy of the system as a function of nuclear coordinates. Such methods are fast and effective within their domain of applicability and good interatomic potential functions are available for many materials. They are, however, limited as they cannot describe any properties and processes, which depend explicitly on the electronic structure of the material. In contrast, electronic structure calculations solve the Schrbdinger equation at some level of approximation allowing direct simulation of, for example, spectroscopic properties and reaction mechanisms. We now present an introduction to interatomic potential-based methods (often referred to as atomistic simulations). [Pg.4528]

To summarize this part, for systems consisting of one or several model conjugated polymer chains initially holding a polaron, all described using the SSH-model extended with an additional part for an external electric field, we have solved the time-dependent Schrbdinger equation for the ir-electrons and the equations of motion for the monomer displacements. [Pg.79]

The Schrbdinger equation (3.10) for modeling free electrons in crystal (Putz, 2006) ... [Pg.287]

Sharp drops after certain sizes in the abundance spectrum indicate enhanced stability of these clusters compared to neighboring sizes. We will try to understand this phenomenon from the behavior of valence electrons in the clusters by invoking simple quantum mechanical models. The simplest model one uses for valence electrons inside a bulk metal is the free-electron theory valence electrons of all the atoms are free to move over the entire volume occupied by the solid [11]. One can use a similar free electron model in case of metal clusters. As the simplest approximation, shape of the cluster can be taken as spherical, and the electrons strictly confined within the sphere. In this hard sphere model, the Schrbdinger equation describing the valence electrons is... [Pg.138]

It should be stressed that another successful approach applied to metal clusters is the jellium model [14], which is often mistakenly considered as the PSM. An important difference between the two models is that although the jellium model treats the electron-electron interaction self-consistently in a positive background potential, the PSM is a one-electron approximation using a (not necessarily homogeneous) confining potential. Thus in order to use the PSM, we solve the Schrbdinger equation for the one-electron in a box problem using different box shapes. [Pg.273]

In the present section, we consider wave functions that, for a given one-electron basis, represent exact solutions to the Schrbdinger equation in Fock space. In the subsequent Sections 5.4-5.8, these solutions to the Schrbdinger equation will serve as benchmarks for less accurate but more practical models of quantum chemistry. [Pg.162]

The Schrodinger wave equation In 1926, Austrian physicist Erwin Schrbdinger (1887-1961) furthered the wave-particle theory proposed by de Broglie. Schrbdinger derived an equation that treated the hydrogen atom s electron as a wave. Remarkably, Schrbdinger s new model for the hydrogen atom seemed to apply equally well to atoms of other elements—an area in which Bohr s model failed. The atomic model in which electrons are treated as waves is called the wave mechanical model of the atom or, more commonly, the quantum mechanical model of the atom. Like Bohr s model,... [Pg.131]

Acceptance of the dual nature of matter and energy and of the uncertainty principle culminated in the field of quantum mechanics, which examines the wave nature of objects on the atomic scale. In 1926, Erwin Schrbdinger derived an equation that is the basis for the quantum-mechanical model of the H atom. The model describes an atom with specific quantities of energy that result from allowed frequencies of its electron s wavelike motion. The electron s position can only be known within a certain probability. Key features of the model are described in the following subsections. [Pg.232]

In Bohr s model of the hydrogen atom, only one number, n, was necessary to describe the location of the electron. In quantum mechanics, three quantum numbers are required to describe the distribution of electron density- in an atom. These numbers are derived from the mathematical solution of Schrbdinger s equation for the hydrogen atom. They are called the principal quantum number, the angular momentum quantum number, and the magnetic quantum number. Each atomic orbital in an atom is characterized by a unique set of these three quantum numbers. [Pg.213]


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See also in sourсe #XX -- [ Pg.40 , Pg.109 , Pg.110 ]




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