Ground-state stability and criticality of two-electron atoms with screened Coulomb potentials using the B-splines basis set

• Autores: Serra, Pablo; Sabre Kais
• Año de publicación: 2012
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Sistemas de Dos Electrones; Fenómenos de Umbral; Métodos Variacionales; Expanciones B-Spline
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

We applied the finite-size scaling method using the B-splines basis set to construct the stability diagram for two-electron atoms with a screened Coulomb potential. The results of this method for two-electron atoms are very accurate in comparison with previous calculations based on Gaussian, Hylleraas and finite-element basis sets. The stability diagram for the screened two-electron atoms shows three distinct regions, i.e. a two-electron region, a one-electron region and a zero-electron region, which correspond to stable, ionized and double ionized atoms, respectively. In previous studies, it was difficult to extend the finite-size scaling calculations to large molecules and extended systems because of the computational cost and the lack of a simple way to increase the number of Gaussian basis elements in a systematic way. Motivated by recent studies showing how one can use B-splines to solve Hartree-Fock and Kohn-Sham equations, this combined finite-size scaling using the B-splines basis set might provide an effective systematic way to treat criticality of large molecules and extended systems. As benchmark calculations, the two-electron systems show the feasibility of this combined approach and provide an accurate reference for comparison.
Fil: Serra, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina
Fil: Sabre Kais. Purdue University. Departament Of Chemistry; Estados Unidos