Ryzhikh, G. G. and Mitroy, Jim (1998). The binding of positronium to lithium. Journal of Physics B: Atomic, Molecular and Optical Physics,31(3):103-107.
The wavefunction of the lithium positride (LiPs) ground state is calculated using an ab initio approach which uses a Gaussian basis with r2 ij correlation factors. The energy of the LiPs ground state, −7:738 55 Hartree, has a total energy more negative than the sum of the positronium (−0:250 Hartree) and lithium (−7:478 04 Hartree) ground states. The ground state is therefore stable against dissociation into LiCPs with a binding energy of −0:010 51 Hartree.
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