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Electronic transitions notations

Figure 5.2 Electronic transitions giving rise to the K X-ray emission spectrum of tin. (a) shows the energy levels and the allowed transitions in X-ray notation. Figure 5.2 Electronic transitions giving rise to the K X-ray emission spectrum of tin. (a) shows the energy levels and the allowed transitions in X-ray notation.
These electron transitions, depicted in Fig. 10 by vertical arrows in bold type (transitions 1, 2, 3, 4, and 6) may be written down in the notation of Sec. I,A as follows ... [Pg.208]

If the direct and reverse electron transitions (3) are in equilibrium (case when electron equilibrium at the surface is established), then a certain portion of the total number of acceptor levels A will be occupied by electrons, while a certain portion of the total number of donor levels D will be unoccupied that is, out of the total number N of the particles of a given kind chemisorbed on unit surface, a certain fraction of particles will be in a state of weak, strong acceptor, and strong donor bonding with the surface. Let us denote, respectively, by N°, N, N+ the number of particles per unit surface in each of these states and introduce the notation ... [Pg.211]

The plan of this chapter is as follows. The next section briefly reviews the CC formalism for the ground state. This is necessary since the LR-CC and EOM-CC approaches start from the CC ground state description. It also introduces some notation that will be used in later sections. Next, the basics of the exact EOM-CC approach are derived, showing how an eigensystem is arrived at. After some aspects of characterizing an electronic transition, EOM-/LR-CC methods that have been developed and implemented are surveyed. The next section presents a numerical assessment of some of the main methods. Finally, a few illustrative applications are summarized. Some aspects of EOM-CC methods are discussed in Chapter 2. The symmetry-adapted cluster configuration interaction (SAC-CI) method can be related to EOM-CC methods. The SAC-CI method and several impressive applications thereof are described in Chapter 4. [Pg.67]

As already mentioned, one of the main weaknesses of the simple reflection method is the fact that the electronic transition dipole moment, (or the transition dipole moment surface, TDMS for polyatomic molecules in Section 4) is assumed to be constant. This weakness will remain in the Formulae (12), (27) and (29) derived below. The average value of the square of the TDM (or TDMS) is then included in amplitude A and A = A /V. In Formulae (3), (3 ) and (3") the mass (or isotopologue) dependent parameters are p and the ZPE. In contrast, W and V., which define the upper potential, are mass independent. This Formula (3) is already known even if different notations have been used by various authors. As an example, Schinke has derived the same formula in his book [6], pages 81, 102 and 111. Now, the model will be improved by including the contribution of the second derivative of the upper potential at Re- The polynomial expansion of the upper potential up to second order in R - Re) can be expressed as ... [Pg.79]

Notation Schemes for Electronic Transitions Intensity and Band Shape 21... [Pg.287]

Absorption of light from the ultraviolet or visible part of the spectrum results in electronic transitions which produce excited states. Two types of excited states are to be considered singlet and triplet. In a singlet state all spins are paired this is almost always the case for the ground state for which the notation S0 is commonly used. Excited singlet states are thus produced if the electronic excitation occurs with complete retention of electron spin. Triplet states are formed when excitation occurs with resultant spin inversion in this case two electrons are unpaired. [Pg.334]

Since Ajej is significantly smaller than Ag t, tetrahedral complexes are high-spin. Also, since smaller amounts of energy are needed for an t2 -f— e transition (tetrahedral) than for an Cg <— t2g transition (octahedral), corresponding octahedral and tetrahedral complexes often have different colours. (The notation for electronic transitions is given in Box 20.3.)... [Pg.562]

For electronic transitions caused by the absorption and emission of energy, the following notation is used ... [Pg.562]

For example, to denote an electronic transition from the e to 2 level in a tetrahedral complex, the notation should be... [Pg.562]

This is a representation for a single activator center. Herein, we use spectroscopic notation for the ground and lowest energy excited states (We will explain this later). Tlius, the electronic energy (involving a one electron transition) is ... [Pg.400]

Fig. 14.1). Only certain electronic transitions are permitted by quantum-mechanical selection rules, which are described in various text books on atomic physics. The x-ray spectral lines are designated by symbols such as Ni K i, Fe K 02. Sn Laa, and U Mcci. The symbol of an x-ray line represents the chemical element (Ni, Fe, Sn, and U) the notations K, L, or M indicate that the lines originate by the initial removal of an electron from the K, L, or M shell, respectively a particular line in the series is designated by the Greek letter a, j8, etc. (representing the subshell of the outer electron involved in the transition), plus a numerical subscript. This numerical subscript indicates the relative strength of each line in a particular series—for example, K i is more intense than Kota. Because there are a limited number of possible inner-shell transitions, the x-ray spectrum is much simpler than the complex optical spectrum that results from the removal or transition of valence electrons in addition. [Pg.384]

We note that the above ground state is a singlet. In order that we obtain a more compact notation we shall explicitly list only those orbitals which participate in electronic transitions in the visible and UV portions of the spectrum. Therefore, for the above configuration we would write... [Pg.128]

To date there is no accepted standard notation for electronic transitions. Without going into detail some of the frequently used notations will be discussed shortly. [Pg.346]


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See also in sourсe #XX -- [ Pg.562 ]

See also in sourсe #XX -- [ Pg.645 ]

See also in sourсe #XX -- [ Pg.104 ]




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Electronic notation

Notation Schemes for Electronic Transitions

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