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Hole orbitals

Within the simple Bohr model used for weakly bound excitons, the radius of the electron-hole orbit is given by... [Pg.141]

Sinha ejt al /135/ also applied the Haque-Mukherjee formalism for IP calculations, but they envisaged a more general computational strategy where not only the principal IP values at the outer and inner valence region but also the satellite peaks with dominant shake-up effects were aimed at. For this, they included all the hole orbitals upto the inner valence region as active. Since the dimension of the model space for the one-hole valence problem is just equal to the number of hole orbitals, it may at first appear surprising that satellite peaks can at all be obtained in this scheme in addition to the main peaks. We should, however, note that the CC equations are inherently non-linear in nature. In fact, at any n-valence level the eq. (7.3.18) involves quadratic... [Pg.349]

In contrast to these cases, for the Rhir heterometallic cluster catalysts inside NaY zeolite the dramatic suppression of hydrogenolysis by increasing the Ir contents is interpreted in terms not of a simple ensemble size effect but of an electronic state associated with the electron deficiency, namely, d-hole orbital of the clusters, as discussed for the Xe NMR chemical shifts on the series Rhe- tlr /NaY (245). The remarkable difference in hydrogenolysis activity between Rh and Ir crystallites inside NaY arises from their electron-deficient sites, which favor C—C bond scission via the alkane carbonium intermediate (177). The C2/C3 selectivity is defined as the ratio of the rates of butane conversion to ethane (k ) to the rates of butane conversion to methane plus propane (k,) ... [Pg.386]

For ionization potentials, the customary EOM basis has the form O/ = a, a , a al,a, a ala ,...). These operators each annihilate one more electron than is created, thus producing an (A — l)-electron function when operating on an -electron function. The operator a removes an electron from an orbital that is occupied in reference determinant, and a al,a removes one electron from a hole orbital and excites a second electron from a hole orbital to a particle orbital. The operator oj, removes an electron from the particle orbital m and a ala removes an electron from a particle orbital and de-excites another electron from a particle orbital to a hole orbital. For electron affinities, the adjoints of the operators in the IP basis from the standard EOM operator basis. [Pg.19]

Wendin also implicitly includes part of the effect of the 5- and higher blocks by replacing hole orbital energies in the denominators of self-energy diagrams with ASCF values for the ionization potentials for the removal of an electron from the orbitals in question. Orbital relaxation is treated in this fashion. This approach is likely to be reasonable for holes in core levels, the situation with which Wendin is concerned, since relaxation effects tend to be greater than changes in correlation for ionization from these levels. [Pg.29]

The denominator corresponding to a given diagram is obtained by taking a factor equal to the sum of the hole orbital energies minus the sum of the particle orbital energies for each horizontal cut the eye draws between successive pairs of either dotted or solid lines. These n - I individual factors are then multiplied to form the denominator. [Pg.81]

This paper is purported to outline how the processes of hole segregation and self-organization can be modeled on the basis of the recently proposed string approach [18-20] involving the concept of pseudoatoms with quantized hole orbitals of rank tj. The condensation of pseudoatoms into pancakes with 1/8 initiates formation of bosonic stripes (BS) classified by the discrete width w =ija, where a -0.385 nm denotes the mean parameter of CuO2 layers. [Pg.129]

Pseudo-atoms with quantized hole orbitals... [Pg.130]

Fig. 2. The Kuo-Herling and PKH model spaces. Single-particle energies are taken from experiment and given in keV. The Kuo-Herling interaction is for either (a) particles above 3 pb or (b) holes below 3<> Pb. Each includes all the particle or hole orbits shown. The two model spaces are not connected. The PKH model space consists of the orbits denoted by solid lines. The interaction includes excitation across the Z =S2,N = 126 energy gap, i.e., the particle and hole spaces are connected. It uses the same single-particle energies as the KH interactions. Fig. 2. The Kuo-Herling and PKH model spaces. Single-particle energies are taken from experiment and given in keV. The Kuo-Herling interaction is for either (a) particles above 3 pb or (b) holes below 3<> Pb. Each includes all the particle or hole orbits shown. The two model spaces are not connected. The PKH model space consists of the orbits denoted by solid lines. The interaction includes excitation across the Z =S2,N = 126 energy gap, i.e., the particle and hole spaces are connected. It uses the same single-particle energies as the KH interactions.
The sum over i can be divided into two parts, one invdving the summation over all particle orbitals, and the other over all hole orbitals except a. [Pg.340]

We will now show that the second-order energy in Eq. (6.77) is a special case of the general expression given by Eq. (6.74). Since we have but a single hole orbital, a = b = 1. Similarly, r = s = 2 so that Eq. (6.74) becomes... [Pg.353]

The term between square brackets can be diagonalized snch that a set of natnral domain-averaged Fermi hole orbitals can be obtained ... [Pg.250]


See other pages where Hole orbitals is mentioned: [Pg.48]    [Pg.59]    [Pg.69]    [Pg.80]    [Pg.450]    [Pg.125]    [Pg.36]    [Pg.85]    [Pg.48]    [Pg.59]    [Pg.337]    [Pg.303]    [Pg.358]    [Pg.3873]    [Pg.387]    [Pg.180]    [Pg.286]    [Pg.250]    [Pg.1054]    [Pg.19]    [Pg.56]    [Pg.232]    [Pg.58]    [Pg.130]    [Pg.258]    [Pg.47]    [Pg.458]   
See also in sourсe #XX -- [ Pg.61 ]

See also in sourсe #XX -- [ Pg.54 ]




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