Breaking Paradigms in Atomic and Molecular Physics

The following sections are included:

• Dedication
• Contents

In this book, we present a number of counterintuitive theoretical results. These fundamental results break several paradigms of quantum mechanics and provide alternative interpretations of some important phenomena in atomic and molecular physics…

The following sections are included:

• A Long-Standing Mystery of the High-Energy Tail of the Linear Momentum Distribution in the Ground State of Hydrogen Atoms or Hydrogen-Like Ions (GSHA)
• Early, Unsuccessful Attempts to Explain the Mystery
• Singular Solutions: General Results on Classes of Potentials to Which They are Applicable
• Engaging Singular Solutions for the Successful Explanation of the Mystery
• Opening a Way to Test Intimate Details of the Nuclear Structure by Performing Atomic, Rather than Nuclear, Experiments

The following sections are included:

• Brief History and Importance of the Corresponding Studies
• Helical States of Diatomic Rydberg Quasimolecules
• Crossings of Classical Energy Terms of Diatomic Rydberg Quasimolecules
• Effects of a Static Magnetic Field: Stabilization of Diatomic Rydberg Quasimolecules
• Effects of a Static Electric Field on Diatomic Rydberg Quasimolecules: Enhancement of Charge Exchange and of Ionization
• Effects of the Screening by Plasma Electrons on Diatomic Rydberg Quasimolecules
• Applications to CL in Plasmas

The following sections are included:

• GHD for the Motion in the Coulomb Potential
• Extending GHD to the Motion in a Modified Coulomb Potential

Indications of a significant role of correlation interactions of electrons have been obtained in studies of collisions in simple atomic systems (H⁺, H⁻, and H⁺). Such correlations are usually attributed to the Coulomb interaction complicated by symmetrization of wave-functions. However, this symmetrization is a consequence of the spin magnetic moments of electrons. The contribution of the spin–spin interaction to the expression for the binding energy appears with a small parameter α² = e⁴/ħ²c², which suggests that it is manifested only in calculation of the fine structure of spectra. The attempt at taking into account the contribution from the spin–spin interaction directly was made as early as in the 1920s in determining excited energy levels of singlet and triplet structures. In contrast to the spin–orbit interaction, the spin–spin interaction depends not on the distance between the electrons and the nucleus, but only on the relative distance between the electrons. However, the relative distance r₁₂ in [5.6, 5.9, 5.10] was replaced by the distance from the nucleus and an excited electron because this electron is always separated from the nucleus by a much larger distance than an unexcited electron. As a result, the role of the singularity |r_ij|⁻³ in the spin–spin interaction in the spatial region in which the distance r₁₂ between the electrons is smaller than the Compton wavelength λ_C = ħ/mc was disregarded. At that time, the interest of researches was mainly concentrated on the description of the fine structure of triplet energy levels. Since the allowance for the spin–spin interaction could only lead to a displacement of terms as a whole, interest in a more detailed account of the spin–spin interaction was lost…

An isolated hydrogen atom emits practically infinite series of spectral lines, corresponding to radiative transitions from the upper level of the principal quantum number n to the lower level of the principal quantum number n₀. (Here and below by “hydrogen atoms” and “hydrogen spectral lines” we mean atoms and spectral lines of hydrogen, deuterium, and tritium.) In other words, there is practically no restriction on how high the number n can be…

The following sections are included:

• Breaking the Paradigm and Revealing Charge-Exchange-Caused Dips (x-dips)
• Classical Model of x-Dips
• Advanced Quantal Theories of x-Dips
• Practical Applications: Experimental Determinations of the Rates of Charge Exchange Between Multicharged Ions Using Observed x-Dips
• Future Prospects

We presented paradigm-breaking results in several areas of atomic and molecular physics. In some cases we used quantal formalism (such as in Chapters 2, 5 and 6), but in other cases we used classical formalism (such as in Chapters 3 and 4). Sometimes there is a misconception that with the advent of quantum mechanics, there is no need for classical calculations. So let us dispel this misconception…

The following sections are included:

• Appendix A: Classical Description of Muonic-Electronic Negative Hydrogen Ion in Circular States
• Appendix B: Helical and Circular States of Diatomic Rydberg Quasimolecules in a Laser Field
• References