A Quantum-Mechanical Model of the Electron

Eric R. Scerri

The historical development of the electronic configuration model is traced and the status of the model with respect to quantum mechanics is examined. The successes and problems raised by the model are explored, particularly in chemical ab initio calculations. The relevance of these issues to whether chemistry has been reduced to quantum mechanics is discussed, as are some general notions on reduction.

P. A. M. Dirac

E. Rosencher, B. Vinter

P. A. M. Dirac

Abstract The new quantum mechanics, when applied to the problem of the structure of the atom with point-charge electrons, does not give results in agreement with experiment. The discrepancies consist of “duplexity ” phenomena, the observed number of stationary states for an electron in an atom being twice the number given by the theory. To meet the difficulty, Goudsmit and Uhlenbeck have introduced the idea of an electron with a spin angular momentum of half a quantum and a magnetic moment of one Bohr magneton. This model for the electron has been fitted into the new mechanics by Pauli,* and Darwin,† working with an equivalent theory, has shown that it gives results in agreement with experiment for hydrogen-like spectra to the first order of accuracy. The question remains as to why Nature should have chosen this particular model for the electron instead of being satisfied with the point-charge. One would like to find some incompleteness in the previous methods of applying quantum mechanics to the point-charge electron such that, when removed, the whole of the duplexity phenomena follow without arbitrary assumptions. In the present paper it is shown that this is the case, the incompleteness of the previous theories lying in their disagreement with relativity, or, alternatetively, with the general transformation theory of quantum mechanics. It appears that the simplest Hamiltonian for a point-charge electron satisfying the requirements of both relativity and the general transformation theory leads to an explanation of all duplexity phenomena without further assumption. All the same there is a great deal of truth in the spinning electron model, at least as a first approximation. The most important failure of the model seems to be that the magnitude of the resultant orbital angular momentum of an electron moving in an orbit in a central field of force is not a constant, as the model leads one to expect.

Plinio Innocenzi

Yung Hsu

In traditional quantum mechanics, electron tunneling is described as a quantum penetration effect through a potential barrier. This paper proposes a new physical framework based on the Energy Gradient Model 2.0 (EGM 2.0), which reinterprets the tunneling phenomenon from the perspective of electron cloud deformation and energy gradient driving. Experiments show that when an external potential is applied to a stable electronic system, the electron cloud distribution is reconstructed without destroying the basic electronic structure. A clear energy threshold exists: below the threshold, only electron cloud deformation and spatial rearrangement occur, which corresponds to the tunneling effect; above the threshold, the original quantum state is destroyed, leading to quantum transition. The EGM 2.0 model unifies the mechanism of electron tunneling and quantum transition, providing a consistent classical-quantum physical explanation.