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Ground states total electric energy

To understand how chemical processes proceed in the gas phase, it is important to distinguish between stable species that can be stored and very reactive species that cannot. The stable species are the initial reactants, any stable intermediates, and the products. Summed up, the concentration of stable species typically correspond to the total concentration of mixture. In a reacting mixture there may, in addition to the stable species, be a number of species that are very reactive. These reactive species may be free radicals, ions, or chemically excited species. A free radical is a species with unpaired electrons, while an ion carries an electric charge. A chemical excitation typically involves an energy level that is significantly higher than the ground state for the species. [Pg.553]

Separation of Electronic and Nuclear Motions. The polarizabilities of the ground state and the excited state can follow an electronic transition, and the same is true of the induced dipole moments in the solvent since these involve the motions of electrons only. However, the solvent dipoles cannot reorganize during such a transition and the electric field which acts on the solute remains unchanged. It is therefore necessary to separate the solvent polarity functions into an orientation polarization and an induction polarization. The total polarization depends on the static dielectric constant Z), the induction polarization depends on the square of the refractive index n2, and the orientation polarization depends on the difference between the relevant functions of D and of n2 this separation between electronic and nuclear motions will appear in the equations of solvation energies and solvatochromic shifts. [Pg.78]

To conclude this section, it emerges that LCT offers an excellent approach to the control of excited-state dynamics. Here, the total electric field is composed out of two components where the first transfers population from the ground to the excited state, and the second steers the excited-state energy absorption. Concerning the efficiency and for the parameters regarded, it is not important if the fields interact successively or simultaneously. [Pg.72]

Commonly this equation and Eq. (35) are used to determine the normalized isotropic distribution. Consideration of Eq. (36) shows that various quantities of the collision processes and a few plasma parameters are involved in its coefficients and naturally have an immediate impact on its solution. With respect to the atomic data of the various collision processes, these are the momentum-transfer cross section Q (U), the total cross sections Qj U), the corresponding excitation or dissociation energies of the ground-state atoms or molecules, and the mass ratio m jM. With regard to the plasma parameters, the electric field strength E and the density N of the atoms or molecules occur, but only in the form of the reduced field strength E/N. All these quantities have to be known for a specific weakly ionized plasma in order to determine the isotropic distribution MU) by solving Eq. (36). [Pg.33]

Approximate wave function and density functional theories provide information about the electronic structure of molecules in their electronic ground state. The information includes the electronic charge density, total energy, electric multipole moments (dipole, quadrupole, octupole, etc.), forces on the nuclei, and vibrational frequencies, which is sufficient to model a wide range of chemical phenomena. For example, equilibrium structures and transition states can be calculated from the forces, and vibrational frequencies are not only useful for the interpretation of vibrational spectra but also enable the calculation of thermo chemical data from first principles. These theories are sufficient to model experimental conditions where only the electronic ground state is significantly populated. [Pg.138]


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See also in sourсe #XX -- [ Pg.39 , Pg.126 , Pg.127 , Pg.128 ]




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ELECTRICAL ENERGY

Electrical grounding

Energy ground state

Ground energy

State electricity

Total energy

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