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Internet Electronic Journal of Molecular Design - IEJMD, ISSN 1538-6414, CODEN IEJMAT
| ABSTRACT - Internet Electron. J. Mol. Des. May 2006, Volume 5, Number 5, 260-286 |
A New Aspect in the Computational Nanomaterial Science: Odd Electrons
in Molecular Chemistry, Surface Science, and Solid State Magnetism
Elena F. Sheka
Internet Electron. J. Mol. Des. 2006, 5, 260-286
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Abstract:
A particular aspect of nanomaterial science concerns a common
essence joining topics that seem absolutely different at first
glance. This is resulted form a vital necessity to consider the
main aspects of the problems at the atomic level. Thus,
molecular chemistry, surface science, and solid state magnetism,
their historical evolution, the language, which implies
characteristic terms in use, original theoretical grounds, etc., are
quite different. If radicals are widely accepted characteristics of
the molecular chemistry, dangling bonds and magnetic electrons
are typical terms for the surface science and magnetism.
However, actually, all the features are of the same origin and are
connected with odd electrons of atoms that form either molecules
or surfaces and magnetic solids. The term stands from the
difference between the number of the atom valence electrons and
that one of the neighboring atoms coupled to the considered one.
The current paper presents the approach application to the
chemistry of fullerenes, surface science of silicon crystal as well
as to the molecular magnetism of both solid polymerized
fullerenes and molecular crystals composed of transitional metal
complexes. The quantum theory of the electron bonding is
suggested as the computational basis for the events. The study
was performed computationally using the unrestricted Hartree-Fock
(UHF) approximation. The AM1 semi-empirical method,
implemented in the CLUSTER-Z1 program, was used for all
computations. The paper concerns the molecular chemistry of
fullerene, surface study of the Si(111)(7×7) and Si(100)(2×1)
surfaces, molecular nanomagnets
Co2(μ-OH2)(OOCCMe3)4
(HOOCCMe3)4 (Co2-molecule)
and Ni2(μ-OH2)(OOCCMe3)4
(HOOCCMe3)4 (Ni2-molecule)
as well as magnetism of polymerized C60 in view of the concept on
effectively unpaired electrons. The concept of effectively
unpaired electrons provides a unique computational basis for
description molecular chemistry of fullerenes, surface study of
silicon surfaces as well as magnetic properties of molecular
nanonagnets and polymerized C60. CLUSTER-Z1 software is
available under request from V. A. Zayets (sheka_elena@mail.ru).
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