Monday, May 4, 2009
Introduction to Solid State Physics.
Conduction electrons contribute to the low heat of metal (the law of Dulong-Petit). Theoretical calculations on the same Drude model shows that the contribution of the electrons in the heat should be considerable. Metal atoms densely packed, but not one, but several types of packages - the crystal lattice. So apart from the dense packing in the formation of the crystal lattice of metal, also played a role and chemical properties of atoms (nuclear skeleton). Metallic bond is due to the association of several outer electrons of atoms of metal in general, these electrons, the conductivity zone. The existence of the zone shown in the well-known experience as a short-term arose during braking current previously promoted the coil, and the number of conduction electrons determined from the experiments of Hall. How to define a "chemical" properties of the atomic skeleton? To do this, define the number of hybrid orbitals atomic skeleton, surrounded by attracted to a zone of conductivity. A diamond packing density of atoms in the crystal lattice is equal to 34 percent, and the coordination number (number of nearest atoms for tsentralnoizbrannogo) equals 4. One hybrid orbital atom diamond accounted for 34 divided by 4 equals 8.5 protsentov.Po analogy to the sodium atom 68 divided by 8 equals 8.5 protsentov.Otsyuda number of hybrid orbitals for atoms thick packages will be equal to 74 divided by 8,5 ravno9 pc . (orbitals). Described in the paper "On the question of the metallic bond in dense packings of chemical elements" http://sciteclibrary.ru/eng/catalog/pages/5216.html (inEnglish) Outer shell electrons, or fill subshell first hybrid orbitals and the remaining electrons are placed in the zone of conductivity. Presumably, in real space, a zone of conductivity should be located in the vicinity of the cell surface Wigner-Zeyttsa. Roughly, it resembles a comb. Therefore, conduction electrons contribute to the low heat of metal, as they in fact are two-dimensional space with a complex surface. A frequency for the conduction electrons in a crystal is connected not only with the lattice constant, but with solid geometry hybrid (valence) shell of atomic orbitals. More ostsilyatsii in experiments de Haas-van Alphen study of the Fermi surface. Given the above set forth, it is clear that the mechanisms of electronic filing and payment levels for the atomic shell and zone of conductivity must be different. A good article is seen that the calculation of material properties can be immediately to the chemical element, but not for empty Cuba Born-Karman. All this probably "dikovato" to quantum mechanics, so will be tolerant of dissent. superconductivity in metal monocrystals Why decided to link the emergence of superconductivity from the lattice thermal vibrations of atoms? Because materials have different isotopes of the element of transition temperature in the superconducting state. Of course, such reliance is but it is insignificant. Superconductivity not depend on the type of lattice. Around the superconductor niobium in the table of many conductors, but not beyond. A thermal vibrations of atoms of nearly the same. Why do other metals from the superconductivity is not found? Thermal fluctuations of atoms are not the main mechanism of superconductivity! Conductivity depends on temperature. But with copper, silver, for some reason at the lowest temperature superconductivity is not observed, and the conductor niobium, which was much worse than copper and silver-temperature superconductivity is. Is it more difficult and lead to the type of crystal lattice of copper. That means no thermal fluctuations in the main here, and some processes in the zone of conductivity. For consideration you need to know the number of electrons, each atom of the lattice of preference to the zone of conductivity. BCS authors argue that the superconductivity is involved in every ten electrons, and according to the theory of rigid body in a simple conduction involved from one to about three electrons from an atom or roughly every tenth or hundredth electron. Nevertheless, the currents of the superconductivity much more normal conduction currents! Something happens to the electrons in the conduction zone! The task set. The zone of conductivity seems to me to-cell surface Wigner-Zeyttsa, which is located between the atoms of the crystal lattice. A large electronic conductivity, and nowhere to stay, once on this surface. The transition to the superconducting state in the zone of the conduction electrons must form a team or become dependent on each other. So in the zone of conduction electrons give the atom should be large in comparison with copper, nickel or silver, which are not superconductors. The number of conduction electrons in metals-elements are presented in the work-http: / / kristall.lan.krasu.ru / Science / publ_grodno.html U vanadium, niobium, tantalum and 5 conduction electrons in the atom and, consequently, the temperature transitions tf = 5.30. .. 9.26 and 4.48 K. U, hafnium, titanium and zirconium to 3 electron, and TC = 0.09 ... 0.39 and 0.65 K. Let the right elements of the table, there is lead, tin, 4-5 electrons and aluminum, galy, indium, thallium have 2-3 electrons, and TC = 1196 ... 1091 ... 3.40 ... 2 39, respectively. We lead and tin tf = 7.19 and 3.72, respectively. What was required to prove. Because the conductivity of the surface area, and the electrons have spin, then in my organization of conduction electrons in the community is by working through his back. -------------------------------------------------- ------------------------------ I am here to say that the conduction electrons are of course as a united, but not as BCS, as they begin play at a distance of several thousands of atoms between which there are more electrons, and then "mate". It is also clear that the number of energy levels in the zone of conductivity is not equal to the number of conduction electrons (as in quantum mechanics), as is the amount equal to the number of conduction electrons from the atoms of crystal lattice, ie 1-5 or a little more. -------------------------------------------------- ------------------------------ conduction electrons contribute to the low heat of metal (the law of Dulong-Petit). Theoretical calculations on the same Drude model shows that the contribution of the electrons in the heat should be considerable. Presumably, in real space, a zone of conductivity should be located in the vicinity of the cell surface Wigner-Zeyttsa. Roughly, it resembles a comb. Therefore, conduction electrons contribute to the low heat of metal, as they in fact are two-dimensional space with a complex surface. This error Drude. A frequency for the conduction electrons in a crystal is connected not only with the lattice constant, but with solid geometry hybrid (valence) shell of atomic orbitals. More ostsilyatsii in experiments de Haas-van Alphen study of the Fermi surface. • Josephson Effect? There were many reports of superconductivity associated magnetic phenomena. Therefore, it seems interesting to place between the two superconductors thin layer of ferromagnetic (eg Fe) or copper-diamagnetics and analyze the results. Do not make any of these sandwiches higher TC? • Increasing the TC. Under the above set out. To improve the TC in metals can offer the following. Negatively charged metal sample and test it.