Molecular-Orbital Energy-Level Scheme for LiH

The and r MO s are placed in the center. The a MO is more stable than the hydrogen Ij valence orbital, and the diagram clearly shows that v is mainly composed of hydrogen Ir, with smaller fractions of lithium 2s and 2p. The v, MO is less stable than the lithium Is valence orbital, and the diagram shows that is composed of lithium 2s and hydrogen Ir, with a much greater fraction of lith- 

The Ipx and Ipy orbitals of Li are shown in the MO column as TT-type MO s. They are virtually unchanged in energy from the Li valence-orbital column, since H has no valence orbitals capable of TT-type interaction. 

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