No abstract

The energy emitted by an electron in course of its transition between two quantum levels can be considered as a dissipated energy. This energy is obtained within a definite interval of time. The problem of the size of the time interval necessary for transitions is examined both on the ground of the quantum approach as well as classical electrodynamics. It is found that in fact the emission time approaches the time interval connected with acceleration of a classical velocity of the electron particle from one of its quantum levels to a neighbouring one.

The formalism allowing for the calculation of the energy and electron density of an entire band of electron states in a crystal from the standing linearwombination-Of-atomic-Orbitals wave functions has been presented.The calculations for an fcc lattice were carried out with a maximum basis of 10 products of the cubic harmonics and spherical Bessel functions and with a maximum basis of 14 products for the sc lattice. A good agreement for the results of the energy with Bloch's theory has been obtained for the critical point as well as for the band limit, whereas the density of states in the energy interval between the critical point and the limit of the band displays sharp oscillations above the Bloch's density of states. %'ith increasing basis the oscillations have a tendency to attenuate. The charge per atom introduced by the entire band of states is equal to about 1.11 for the fcc lattice and slightly over 1.5 for the sc lattice, whereas the charge in Bloch's band is equal to 1 in both cases.