Self-Consistent-Field Atomic Wavefunctions from Efficient Nested Basis Sets

Abstract

Constrained self‐consistent‐field wavefunctions are reported for the ground‐state neutral atoms, He–Ne, in which each atomic orbital is a linear combination of Slater‐type orbitals. A more efficient use of the basis set chosen reduces the number of parameters to be optimized while maintaining the energy equal to within five significant figures to the energy of the fully optimized basis set. The reduction in the number of independent linear and nonlinear parameters is achieved by forcing a certain long‐range behavior and a nuclear cusp condition. In one set of calculations the orbitals are forced to behave asymptotically as ${\phi }_i\mathrm{\hspace{0.17em}\sim \hspace{0.17em}}\exp {\text{[−r(−\hspace{0.17em}2}}_{\mathrm{\epsilon i}}{)}^{\text{1/2}}]$ , where ${\epsilon }_i$ is the orbital energy. In the second set of calculations, the orbitals are also forced to exactly obey the nuclear cusp condition.