Page 41 - Strategies and Applications in Quantum Chemistry From Molecular Astrophysics to Molecular Engineer

26 C.CHAVY ET AL.
for Si) the deviation is still smaller than 10% of the value of the orbital at the last
extremum.

These results illustrate the fact that the orbital is weakly dependent of the energy
e at the peak for r=0 (Cusp theorem) but also down in the valley and even on the
next hill if any (Valley theorem).

In the case of the p and d orbitals (fig. 4-6) the deviations are larger than the
deviations obtained with s orbitals. This is simply because the magnitudes of the
p and d orbitals are larger than those of the s orbitals for r ca. 1.0 B due to the