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Текст реферата On the problem of crystal metallic lattice in the densest packings of chemical elements
ON THE PROBLEM OF CRYSTAL METALLIC LATTICE IN THE
DENSEST PACKINGS OF CHEMICAL ELEMENTS
G.G FILIPENKO
www.belarus.net/discovery/filipenko
sci.materials(1999)
Grodno
Abstract
The literature generally describes a metallic bond as
the one formed by means of mutual bonds between atoms' exterior
electrons and not possessing the directional properties. However,
attempts have been made to explain directional metallic bonds, as a
specific crystal metallic lattice.
This paper
demonstrates that the metallic bond in the densest packings
(volume-centered and face-centered) between the centrally elected atom
and its neighbours in general is, probably, effected by 9 (nine)
directional bonds, as opposed to the number of neighbours which equals
12 (twelve) (coordination number).
Probably, 3
(three) "foreign" atoms are present in the coordination number 12
stereometrically, and not for the reason of bond. This problem is to
be solved experimentally.
Introduction
At present, it is
impossible, as a general case, to derive by means of
quantum-mechanical calculations the crystalline structure of metal in
relation to electronic structure of the atom. However, Hanzhorn and
Dellinger indicated a possible relation between the presence of a
cubical volume-centered lattice in subgroups of titanium, vanadium,
chrome and availability in these metals of valent d-orbitals. It is
easy to notice that the four hybrid orbitals are directed along the
four physical diagonals of the cube and are well adjusted to binding
each atom to its eight neighbours in the cubical volume-centered
lattice, the remaining orbitals being directed towards the edge
centers of the element cell and, possibly, participating in binding
the atom to its six second neighbours /3/p. 99.
Let
us try to consider relations between exterior electrons of the atom of
a given element and structure of its crystal lattice, accounting for
the necessity of directional bonds (chemistry) and availability of
combined electrons (physics) responsible for galvanic and magnetic
properties.
According to /1/p. 20, the number of
Z-electrons in the conductivitiy zone has been obtained by the
authors, allegedly, on the basis of metal's valency towards oxygen,
hydrogen and is to