Abstract
Experimental evidence for the existence of polylithiated molecules such as CLi6, Li3O, Li4O, Li3S, Li4S, and Li4P has been obtained by means of Knudsen-effusion mass spectrometry. These polylithiated molecules with nine or more of valence electrons are called hyperlithiated or hypervalent molecules; violating at least formally the octet rule. The dissociation energies, atomization energies and ionization energies of these hyperlithiated molecules were determined. The experimental values agreed fairly well with the theoretical values, and the theoretical prediction that hyperlithiated molecules were thermodynamically more stable than corresponding octet molecules such as CLi4, Li2O, Li2S, and Li3P was verified through a series of experimental work.
