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6 total sentences available.
Molecular hydrogen is by the way a very difficult species to form in the gas phase by radiative association of H atoms, mainly because the protomolecule formed in this way is vibrationally highly excited and cannot get rid of the energy excess to enter inside the potential well and reach stability in a time short enough to avoid breaking.
Source: wiktionary
This is a consequence of the fact that the protomolecule, just formed in a high vibrational level, has to release quickly (roughly in a time comparable with its vibrational period) an energy excess of about four and a half electronvolt.
Source: wiktionary
As pointed out many years ago (see, for example, Duley and Williams, 1984), molecular hydrogen cannot form efficiently in the gas phase in the ISM, when H atoms are neutral and in the ground state, since three-body reactions are necessary to take out the excess energy quickly enough before the protomolecule falls apart.
Source: wiktionary
It is most probable that all matter is simply the allotropic expression of one element and that the protomolecule is the union of the positively and negatively electrified etheric corpuscle.
Source: wiktionary
Showing 4 of 6 available sentences.
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.