Рис.1. Основные типы кристаллических решеток:
а – объемно-центрированная кубическая; б – гранецентрированная кубическая; в – гексагональная плотноупакованная.

It is said that the internal periodic electric field of the ions of the crystal lattice affects the distribution of electrons over the energy levels in solids. We make a rough calculation of the effect on the electron in the conduction band of the charge of the nucleus of the atom (ion) and the electron of the atomic core on the outer shell of the ion. Let the distance between atoms be 4 angstroms, and between the outer electron of the core and the conduction electron of 0.25 angstrom, then multiply 0.25 by 4 to give unity to the force and find an element with atomic number 64 whose charge of the nucleus acts on the conduction electron with the by force. Gadolinium. For elements with atomic numbers greater than 64, the main influence will be exerted by the periodic field of ions, while for elements with atomic numbers less than 64 the periodic field of the outer electrons of the atomic core will be decisive. Roughly, of course, nevertheless the band theory needs to be reviewed.

   Ladies and Gentlemen, I apologize for the cheap translation by Google.

Some ask, what, why, why, how.

  The main problem lies in the fact that by using X-rays determined the crystal lattices of different materials, and why they are, and not the other is not yet known. For example copper crystallizes in the fcc lattice, and iron in the BCC, which when heated becomes FCC is used for heat treatment of steels. Copper by heating the crystal lattice does not change.
    The literature provides many factors influencing the crystallization so I decided to remove them as much as possible, and metal model of the article say so perfect, that is, all atoms are identical (pure metal) without inclusions without introduction, without defects, etc. using Hall effect and other data on the properties and calculations Ashcroft and Mermin-, my main determining factor in the type of lattice appeared core of the atom or ion, which has turned out as a result of the transfer of the electrons in the conduction band.
   It turned out that the metallic bond is due not only to the socialization of electrons, and the outer electrons and atomic cores, which determine the direction or type of crystal lattice.Changing the metal lattice type it may be associated with the transition of an electron in the conduction band or return it from this zone. The phase transition.I think that phase transitions are possible without changing the lattice type. For example copper. I suppose that in the conduction band can be in copper and one electron from an atom, or maybe two, depending on external conditions.

On the periodicity of the crystal. We know that it is associated with the lattice constant, or in other words, the distances between the nuclei of the atoms of the element. But another frequency for the conduction electrons follows from this work, it creates the valence electrons or electrons of the atomic core, which is probably localized and are on the boundary of the conduction band.

Why body-iron and copper have a face-centered cubic lattice?

Why body-iron and copper have a face-centered cubic lattice?

 Now, when microelectronics turned into nanoelectronics and threatens to go to angstromelektronics, it is important to know the patterns of distribution of atoms (atomic size is measured in units of Angstroms) in the crystal lattice of the single crystal.