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Stationary orbits

The energy and length scales that are appropriate at the atomic level are those set by the ionization potential and first Bohr radius of the hydrogen atom. In SI units the energy and radius of the nth Bohr stationary orbit are given by... [Pg.268]

Earth satellites relaying microwave signals from the ground have increased the distance that can be covered in one hop. Microwave repeaters in a satellite in a stationary orbit 22,300 mi (35,881 km) above the earth is high enough to reach one third of the earth s surface. Microwave signals can be relayed by just one satellite repeater when that satellite is simultaneously above the horizon for both the earth-bound transmitter and the receiver. [Pg.342]

As noted earher, Bohr had suggested the quantization of Ruthford s model of the atom. Although he was not aware of the work of Balmer and Paschen when he wrote the first version of his 1913 article, he had incorporated Planck s constant h into his model, which turned ont to be an important decision. Bohr assnmed that the absorption or emission of radiation can occnr only by jnmps of the electron from one stationary orbit to another. (See Fignre 1.) The energy differences between two snch allowed orbits then provided the characteristic freqnencies of the emitted light. [Pg.108]

The quantum conditions by means of which the stationary orbits are selected can be expressed in the form that a certain mechanically defined magnitude is an integral multiple of Planck s constant h. In the case of the oscillator this magnitude is W/v the question is, what is to take the place of this quantity in the case of other systems ... [Pg.53]

Not only these term differences, but also the terms themselves, have a physical significance. Thanks to our hypothesis regarding the potential energy, which we have supposed to vanish at infinity, the magnitude W of the energy constant denotes the work which is necessary to remove an electron from its stationary orbit to infinity and to bring it to rest there (relatively to the nucleus). If the stationary orbit of the electron is that of the normal state, then this work is the work of ionisation. [Pg.154]

The realization that electrons have wave properties leads at once to an interpretation of Bohr s hypothesis of stationary orbits. Figure LI shows the de Broglie wave associated with an electron in a Bohr orbit of radius r. If the circumference Inr is equal to an integer n multiplied by the wavelength X, the wave will fit into the orbit an integral number of times, and constructive interference will occur Figure. Xa). [Pg.5]

When a perturbation is introduced, the stationary condition means that the orbitals must change, which may be described as a mixing of the unperturbed MOs. In other words, the stationary orbitals in the presence of a perturbation are given by a unitary transformation of the unperturbed orbitals (see also Section 3.6). [Pg.327]

Ballistic missiles, satellite launchers and space launchers are all referred to by the general name of launcher. The difference between these three types of trajectories (Earth-Earth, Earth-stationary orbit. Earth-space) results from the value of the speed reached at the end of the propelling phase less than 7000 m s l, falling between 7000 and 11000 m s over 11000 m s respectively. [Pg.55]

However, the periodicity condition (4.518) for paths is to be maintained and properly implemented in approximating the effective-classical partition function (4.525) being, nevertheless, closely and powerfully related with the quantum beloved concept of stationary orbits defined/described by periodic quantum waves/paths. This way, the effective-classical path integral approach appears as the true quantum justification of the quantum atom and of the quantum stabilization of matter in general, providing reliable results without involving observables or operators relaying on special quantum postulates other than the variational principles - with universal (classical or quantum) value. [Pg.505]

For stationary states, analogous to Bohr s stationary orbits where the potential energy is independent of time, 4 (x, y, z, t) can be factored into a time-dependent term (j) t) and a time-independent term i//(x, y, z), as shown in Equation (3.42). [Pg.68]

Stationary orbitals (including both occupied and virtual orbitals), namely... [Pg.216]


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See also in sourсe #XX -- [ Pg.201 ]




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