protomolecules

Noun

protomolecule (plural protomolecules)

1. A collection of unstably bound atoms that has the potential to form a molecule if the structure can shed sufficient energy.
   • 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...1991, Ezio Bussoletti, G. Strazzulla, Solid-state astrophysics: 27 June-7 July 1989, →ISBN, page 385
2. A relatively simple molecule from which a more complex molecule is derived.
   • 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.1912, George Frederick Shrady, Thomas Lathrop Stedman, Medical Record