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Stationary state energy levels

Transitions between Stationary State Energy Levels... [Pg.15]

Typically the time-independent Hamiltonian is used and the stationary state-energy levels are determined. [Pg.393]

The harmonic-oscillator stationary-state energy levels (4.47) are equally spaced (Fig. 4.1). Do not confuse the quantum number v (vee) with the vibrational frequency V (nu). [Pg.69]

Fig. 6. Schematic representation of the collisional dependence of individual state energy levels. The time variation of Ej (t) — Eg(t) during a collision is small compared to their asymptotic separation, condition (3.13). The pair j(r) and Ef(t) obey condition (3.1S) and produce a point of stationary phase, Eq. (3.16), at tg. Fig. 6. Schematic representation of the collisional dependence of individual state energy levels. The time variation of Ej (t) — Eg(t) during a collision is small compared to their asymptotic separation, condition (3.13). The pair j(r) and Ef(t) obey condition (3.1S) and produce a point of stationary phase, Eq. (3.16), at tg.
For the particle in a one-dimensional box of length I, we could have put the coordinate origin at the center of the box. Find the wave functions and energy levels for this choice of origin. The particle-in-a-box time-independent Schrodinger equation contains the constants h and m, and the boundary conditions involve the box length 1. We therefore expect the stationary-state energies to be a function of and//that is, =/(/i, ,/). [We found = ( /8) (/i /m/ ).]... [Pg.33]

As compared to the MOM approach discussed earlier, other methods for treating metastable states are somewhat more involved, and understanding them requires a few concepts that go beyond bound-state quantum mechanics. One idea that is needed is the notion of analytic continuation of the bound-state energy levels into the complex plane. A heuristic explanation of why this is necessary goes as follows.In some ways, a temporary anion resonance resembles a stationary state of the molecular potential, at least in the sense that the probability distribution is relatively localized around the molecule (see Figure 13). At the same time, however, the resonance has a finite lifetime and will ultimately tunnel out of the potential that is responsible for it. In view of these facts, it... [Pg.477]

Atomic and Molecular Energy Levels. Absorption and emission of electromagnetic radiation can occur by any of several mechanisms. Those important in spectroscopy are resonant interactions in which the photon energy matches the energy difference between discrete stationary energy states (eigenstates) of an atomic or molecular system = hv. This is known as the Bohr frequency condition. Transitions between... [Pg.311]

The MP2/TZDP optimized structures were then used to calculate the stationary state geometry force constants and harmonic vibrational frequencies, also at the MP2 level. These results serve several purposes. Firstly, they test that the calculated geometry is really an energy minimum by showing all real frequencies in the normal coordinate analysis. Secondly, they provide values of the zero-point energy (ZPE) that can be used... [Pg.18]

The traditional treatment of molecules relies upon a molecular Hamiltonian that is invariant under inversion of all particle coordinates through the center of mass. For such a molecular Hamiltonian, the energy levels possess a well-defined parity. Time-dependent states conserve their parity in time provided that the parity is well defined initially. Such states cannot be chiral. Nevertheless, chiral states can be defined as time-dependent states that change so slowly, owing to tunneling processes, that they are stationary on the time scale of normal chemical events. [22] The discovery of parity violation in weak nuclear interactions drastically changes this simple picture, [14, 23-28] For a recent review, see Bouchiat and Bouchiat. [29]... [Pg.178]

The atom has only specific, allowable energy levels, called stationary states. Each stationary state corresponds to the atom s electrons occupying fixed, circular orbits around the nucleus. [Pg.126]

The success of this extended STIRAP scheme can be traced to the fact that the basis of the subset of dressed eigenstates of the coupled matter-radiation field is a stationary state representation. In this representation, all couplings are already taken into account via the identity of and the locations of the energy levels. The contribution of the background states to the population transfer process is then limited to effects associated with nonresonant coupling to the field, and if these background states are far off resonance such effects are small. [Pg.87]

Suppose a system has the stationary-state wave function [/ = Nexp( — bx4), where N and b are constants. Find the potential-energy function V(x) for the system. Hint note that the zero level of energy is arbitrary, and can be chosen at our convenience. [Pg.293]

ATOMIC ENERGY LEVELS. 1. The values of the energy corresponding to the stationary states of an isolated atom. 2. The set of stationary states in which an atom of a particular species may be found, including the ground state, or normal state, and the excited states,... [Pg.159]

ENERGY LEVEL. A stationary state of energy of any physical system. The existence of many stable, or quasi-stable, slates, in which the energy of the system stays constant for some reasonable length of time, is an essential characteristic of quantum-mechanical systems, and is the basis of large areas of modem physics. [Pg.564]

With a general understanding of the form of nuclear potentials, we can begin to solve the problem of the calculation of the properties of the quantum mechanical states that will fill the energy well. One might imagine that the nucleons will have certain finite energy levels and exist in stationary states or orbitals in the nuclear well similar to the electrons in the atomic potential well. This interpretation is... [Pg.140]

The CH(F)=XH2 series has planar equilibrium structures for X = C and Si, while for X = Ge, Si and Pb the optimized fraws-bent geometry is more stable (Table 2). The planar forms for the last three X atoms are calculated to be 0.3, 2.3 and 5.4 kcalmol-1 higher in energy than the respective fraws-bent forms. DFT/CEP-5ZP calculations using the B3LYP functional do not show stationary states in the planar geometry for the Sn and Pb compounds, while, as noted above, at the ab initio CAS(4,4)/CEP-DZP level... [Pg.15]

The theory discussed here gives a special role to the stationary states of the molecular hamiltonian. In particular, there are stationary electronic states, not a set of electrons. For example, the hydrogen atom cannot be seen as formed by one proton plus one electron. It is the electronic spectra which define it, not the model we use to calculate the energy levels and wave functions. This may sound strange but consider a thermal neutron. This system decomposes into one proton plus an electron and a neutrino. One cannot say that a neutron is made of such particles. Matter may exist in different kinds of stationary states processes can be seen as changes among them. [Pg.43]

Electrons move in each stationary energy state in a circular path. These circular paths are called energy levels or shells . [Pg.11]

When an electron is in a stationary state, the atom does not emit (radiate) light. However, when an electron falls back to a lower energy level from a higher one, it emits a quantum of light that is equal to the energy difference between these two energy levels. [Pg.11]


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Stationary levels

Stationary state

Transitions between Stationary State Energy Levels

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