Surprising New Bohr Models for H 2 and H 2 +

Abstract

Niels Bohr constructed the first version of quantum mechanics. It has been called “old quantum mechanics” with a connotation of being obsolete. It is logically consistent, however, and deserves the name of simple quantum m e chanics (SQM). It differs only from the semiclassical approximation by assuming that the average position and average velocity of an electron can be sharply defined on closed orbits. This assumption does not contradict Heisenberg’s uncertainty relations, since the quantization rule means that the electron can be anywhere on this orbit when it allows for stationary waves. This approach was remarkably efficient for one electron in hydrogen atoms and even for the electron pair in hydrogen molecules. However, dissociation of H 2 and determination of the orbit of the single electron in H 2 + led to problems that remained unsolved for more than 100 years. Their solution, presented here, yields more physical insight and reveals, for instance, that mutual polarization of two hydrogen atoms can yield a metastable state.