II International Symposium on Carbon for Catalysis ABSTRACTS

OP-I-26
FEATURES OF ELECTRON STRUCTURE AND CHARACTERISTICS OF LOW-
DIMENSIONAL DEFECTS OF PYROLITIC GRAPHITE
Balashov E.M., Dalidchik F.I.
Semenov Institute of Chemical Physics RAS, Moscow, Russia
e-mail: dalidchk@center.chph.ras.ru
New regular method is developed for constructing exactly solvable models which
describe the variations of electron spectra of low-dimensional 1D-, 2D- crystals and carbon
tubulen type of one-dimensional structures at the formation of different structural defects
(vacancies, substitutional impurities, interstitial atoms, and adsorbed particles) or the
switching of various interactions (exchange interactions between isolated atoms involving in
different system or the interparticle interactions linking electrons with quasi-particles
(phonons and excitons)). These variations can not be reproduced by the perturbation theory.
The analytical expressions are obtained to determine the conditions in spectra of carbon
nanotubes for formation of
- discrete levels of stationary and quasi- stationary states localized close to the
monoatomic and polyatomic vacancies;
- discrete levels of stationary and quasi- stationary states localized close to the sites of
dot exchange coupling;
- 1D zones of stationary and quasi-stationary states localized along the line of contacts
of carbon nanotubes (CNT) with current-carrying substrates which are used in studies
of CNT electron structure by the scanning tunneling spectroscopy (STS) methods;
- zones of forbidden states in spectra of CNT’s with superlattices of dot perturbations
(defects and weak exchange coupling).
The obtained results determines the optimal conditions that the CNT phonon spectra can
be studied by the scanning tunneling spectroscopy methods.
By the STM-STS methods, the atomic and electron structure of zero-dimensional defects
of pyrolitic graphite (surface monoatomic and polyatomic carbon vacancies) are studied. It is
observed the spectroscopic effects caused by the formation of near Fermi resonances (for
monoatomic vacancies) and near Fermi energy zones without dispersion.
This work was supported by Russian Foundation for Basic Research, project no.05-03-
33274-a and no.06-03-32457-a.
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