Charge distribution in C 60 crystal doped by electric field

Abstract

The calculations of the charge distribution in the C 60 -based FET structure are presented. A simple model is proposed to describe the distribution of injected electrons or holes between two-dimensional layers. The calculations show that the relative layer charges are independent on the total amount of injected charges. The charge density is maximal on the surface layer and drops exponentially with the depth increase. The relative portions of injected charge involved in the top layer are 73 and 64 per cent in the case of electron and hole injection, respectively. Thus, the degree of charge localization on the crystal surface turns to be markedly different from the result obtained earlier within the tight-binding model predicting near-complete localization for the charge concentration providing superconductivity.

Jahn–Teller Instability of Correlated C60 Anions

“…As shown in [4], the long-range electron repulsion is necessary to predict the observed order of the ground-state energies of C 60 fullerene anions, thus, suggesting the restricted applicability of the Hubbard model for the calculations of the many-electron states of fullerenes and fullerides. The correlated motion of extra electrons in an anion is characterized by the trend to be separated that leads to some delocalization of the electronic density.…”

“…Namely, the ground states 2 T 1u (N ¼ 1), 3 T 1g (N ¼ 2, 4), and 4 A u (N ¼ 3) have really the highest multiplicity for a given N and the highest degeneracy for a fixed multiplicity. These characteristics are also the same when the electron correlation is taken into account.…”

“…The next unoccupied orbital above t 1u is t 1g , and it is rather close in energy. Basing on this fact, the ordering of terms different from the Hund ordering is obtained for the C 60 anion ground states derived from the accounting of the two-orbital active space [2][3][4].…”

Electron Correlation Effects in Multicharged Ions of Icosahedral C60Fullerene

“…To get comparable results, the same model Hamiltonian and unified approximations for wave functions are used in the calculations of many-electron states. We apply the configuration-interaction (CI) approach using the molecular-invariant technique [10,11] to take full advantage of the high fullerene symmetry. This approach provides a unified treatment of the different C 60 charge forms, and the results easily tabulated for different potentials are equivalent to those obtained within the straightforward CI approach.…”

Distribution of field-induced charges in C60 fullerite

“…In the preliminary brief report [11] the equations for the charge distribution are solved numerically. Considering that approach in more detail here, we present analytical solutions of the equations defining the charge distribution in the C 60 -based FET structure in the limits of thin and thick crystals.…”