Potential Energy Expectation Value for Lithium Excited State (1s2s3s)

He purpose of the present work is to calculate the expectation value of potential energy for different spin states (ααα ≡ βββ,αβα ≡ βαβ) and compared it with spin states (αββ , ααβ ) for lithium excited state (1s2s3s) and Li- like ions (Be+,B+2) using Hartree-Fock wave function by partitioning techanique .The result of inter particle expectation value shows linear behaviour with atomic number and for each atom and ion the shows the trend ααα < ααβ < αββ < αβα .