The production of molecular positronium

@article{Cassidy2007ThePO,
  title={The production of molecular positronium},
  author={D. B. Cassidy and Allen P. Mills},
  journal={Nature},
  year={2007},
  volume={449},
  pages={195-197}
}
It has been known for many years that an electron and its antiparticle, the positron, may together form a metastable hydrogen-like atom, known as positronium or Ps (ref. 1). In 1946, Wheeler speculated that two Ps atoms may combine to form the di-positronium molecule (Ps2), with a binding energy of 0.4 eV. More recently, this molecule has been studied theoretically; however, because Ps has a short lifetime and it is difficult to obtain low-energy positrons in large numbers, Ps2 has not… 
Optical spectroscopy of atomic and molecular positronium
Positronium (Ps) is a purely leptonic hydrogen-like atom formed from an electron and a positron. Since the interactions of electrons and positrons are thought to be almost entirely electromagnetic,
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It is demonstrated that the positron density enclosed in each atom is capable of stabilizing interactions with the electron density of the neighboring atom, and this electrostatic interaction suffices to make the whole system bonded against all dissociation channels.
Antimatter Atomic Physics
Positronium, the atom formed from an electron and a positron, is a gateway to very cold antihydrogen atoms and possibly a γ-ray laser. Positronium (Ps), the bound state of an electron and its
Possible experiments with high density positronium
  • A. Mills
  • Materials Science
    INTERNATIONAL CONFERENCE ON SCIENCE AND APPLIED SCIENCE (ICSAS) 2019
  • 2019
Although it can probably only exist within a confining potential, a positronium (Ps) Bose-Einstein condensate (BEC) would be interesting because it could be viewed as the ultimate member of Wheeler’s
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TLDR
The structures of the above exotic chemical entities based on exact atomic radii are evaluated here for the first time and are of help for a better understanding and further development of the chemistry and physics of these short lived compounds.
Experiments with Dense Low-Energy Positrons and Positronium
Abstract This chapter reviews the steps required to capture and accumulate copious numbers of low-energy positrons, and to form positronium (Ps) atoms at low energies. We then relate the few results
Positronium – Hydrogen Like and Unlike
A brief review on positronium, Ps, hydrogen-like system built from positron and electron, is outlined from its beginning in 1935, the first theoretical study on this relatively stable
Positronium formation via excitonlike states on Si and Ge surfaces
Recent experiments combining lifetime and laser spectroscopy of positronium (Ps) show that these atoms are emitted from p-Si(100) at a rate that depends on the sample temperature, suggesting a
Two positrons can form a chemical bond in (PsH)2.
TLDR
This is the first time two positrons are shown to behave like two electrons in ordinary matter, enlarging the definition of what is a chemical bond dating back to Lewis.
Covalent bonds in positron dihalides.
TLDR
Analysis of the electron and positron densities points out that the formation of positron covalent bonds underlies the stabilization of the otherwise repelling dihalides, revealing that positronic bonding can reach far beyond the previously addressed e+[H-H-] molecule.
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