Positronium hydride (PsH) is a normally rare molecule consisting of one proton, two electrons, and one positron. The binding energy is 1.1 eV. The lifetime of the molecule is 0.65 nanoseconds in 3-space. Positronium deuteride also has the same lifetime in 3-space. In 1-space, things can be different.
When protons are adsorbed into a surface layer as "spillover" the geometry can sometimes approach one dimension. In that case PsH may not be so rare, and the 1.1 eV gain could be the expected result as Ps returns to 1-space. Activated carbon is known to adsorb hydrogen in this way, as is nickel and palladium. The decay of positronium is normally detected by the two gamma ray photons of 511 keV of energy. Even when gamma photons are not seen or rarely seen, the binding energy of PsH could be available in 3-space, and the decay energy (of the gamma) stays in the vacuum as negative energy. The structure of PsH is normally a comparatively large diatomic molecule, with a radius of many angstroms. However, a DDL version of PsH should be available whenever protons are adsorbed into a spillover, catalyst like nickel. Essentially this is what is known as IRH or inverted Rydberg hydrogen. Jones Addendum: "Portal site mediated adsorption" is a model for site-selective activated gas adsorption in metallic or metallic-dielectric catalytic systems. In such systems, geometry- in the form of "edge and corner" sites can exhibit significantly lower adsorption enthalpies. A common defect site which facilitates proton adsorption is found in carbon. These geometric sites can serve as "portals" for very rapid proton adsorption into metals. The phenomenon is part of the larger "spillover" effect. The PSMA model explains seemingly inconsistent observations of gas adsorption thermodynamics and kinetics in catalytic systems, and it has been successfully applied to bimetallic catalytic systems where synergistic activity is observed.
<<attachment: winmail.dat>>
