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Encaged atoms

An alternative simple modeling of doped fullerenes, specifically, A C6o, was developed initially in [34]. It was then used extensively in a number of photoionization studies of thus encaged atoms [34 41], The method is based on approximating the C60 cage by a spherical potential V(r) which differs from zero only within an infinitesimally thin wall of a sphere of radius RC/ the latter being considered the C60 radius, Rc = 6.639 au [47] ... [Pg.19]

Here, Iq is the electron affinity of C60 (Iq = 2.65 eV [50]). Thus, the 5-potential model ignores the finite thickness nature of the carbon cage within the model, A = 0. Furthermore, in the framework of this model, the size of the embedded atom ra is considered to be so small, compared to the size of C60, that the ground state electronic wavefunctions of the embedded atom coincide exactly with those for a free atom. In other words, the model assumes no interaction between the ground state encaged atom and the carbon cage at all. Therefore, the model is applicable only to the deep inner subshells of the encaged atom. As for the carbon atoms from... [Pg.19]

Here, U(r) is the self-consistent field of the encaged atomic core "felt" by an electron in the continuous spectrum. To determine Pki(r), one must solve (9) separately for r < Rc and r > Rc and match both solutions at r = Rc with the help of boundary conditions. [Pg.20]

In the framework of the A-potential model, combined with the frozen-cage approximation, the problem is solved simply. Namely, HF wavefunctions and energies of the encaged atom, solutions of the extended to encaged atoms Hartree-Fock equations (2), must be substituted into corresponding formulae for the photoionization of an nl subshell of the free atom, Equations (18)-(26), thereby turning them into formulae for the encaged atom (to be marked with superscript " A") rrni(o>) —> a A(co), Pni(fi>) Yni o>) - and 8ni((o) - 8 A(co). This accounts... [Pg.25]

Thus, F(oj) has a complicated codependence. The latter will be mirrored in the photoionization cross section of the encaged atom. Correspondingly, the photoionization cross section of the encaged atom in the dynamical-cage approximation might differ greatly from that in the frozen-core approximation, both quantitatively and qualitatively. [Pg.29]

The discovery of confinement resonances in the photoelectron angular distribution parameters from encaged atoms may shed light [36] on the origin of anomalously high values of the nondipole asymmetry parameters observed in diatomic molecules [62]. Following [36], consider photoionization of an inner subshell of the atom A in a diatomic molecule AB in the gas phase, i.e., with random orientation of the molecular axis relative to the polarization vector of the radiation. The atom B remains neutral in this process and is arbitrarily located on the sphere with its center at the nucleus of the atom A with radius equal to the interatomic distance in this molecule. To the lowest order, the effect of the atom B on the photoionization parameters can be approximated by the introduction of a spherically symmetric potential that represents the atom B smeared over... [Pg.37]

It turns out [20,29], that electron correlation may work in the "opposite direction" in encaged atoms compared to that in the free atoms, thus termed reversed electron correlation. [Pg.54]

From this figure, it is evident, that, for the free atoms, the peak of the valence ns probability distribution moves to larger r with increasing Z. For this reason the valence ns probability density in the encaged atoms is progres-... [Pg.54]

The RRPA calculated [29] valence ras photoionization cross sections for both the free and encaged atoms, at the frozen-cage approximation level, are displayed in Figures 22-24. To demonstrate the importance of electron... [Pg.55]

A remarkable modification of oscillator strengths in encaged atoms, A compared to free atoms, and the consequences of such modification for the... [Pg.57]


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Encaged atoms cages

Encaged atoms dynamical-cage approximation

Encaged atoms frozen-cage approximation

Encaged atoms molecules

Encaged atoms photoionization

Encaged atoms photoionization cross section

Photoionization of encaged atoms

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