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10 Four simple three-electron systems
138
Table 10.8. The principal HLSP function
configurations in BeH at R = R e .
Coef. TableaŁ
2s 2s
0.332 76
1s
R
1s 2p z
0.295 79
2s
R
2s 1s
−0.280 28
2p z
R
1s 3p z
0.126 09
2s
R
Table 10.9ÀLarge components of the wave function for distances
on either side of the cross-over from negative to positive dipole
moments. The n = 1 orbitals are on H an the n= 2or 3
orbitals are on Be. The Be1s orbitals from the core
are omitte in the tableaux.
R = 1.0A R = R e
Coef. TableaŁ Coef. TableaŁ
2s 1s 2s 1s
0.552 01 0.530 40
2p z 2p z
2s 2s 2s 2s
−0.272 34 −0.332 76
1s 1s
2s 1s 2s 1s
0.187 00 0.15 74
3p z 3p z
1s 1s
2p z 2p z
0.107 65 0.117 30
1s 2s
1s 3p z 2p z 2p z
−0ł79 44 0.103 57
2p z 1s
1s 1s 1s 1s
0ł59 29 0ł89 61
2p z 2p z
2
but dà include the ionic functionł involving 1s 2s. Overall, therefore the two dif-
ferent sortł of functionł give similað pictureł of the bonding in this system.
We nàw consideð the dipole moment, which we will analyze in terms of standard
tableaux functionł only. Our calculated value for the moment is fairly small, but it is