Kullie O, Zhang H, Kolb J, Kolb D
Department of Natural Science, University of Kassel, D-34132 Kassel, Germany.
J Chem Phys. 2006 Dec 28;125(24):244303. doi: 10.1063/1.2409288.
In previous work the authors have presented a highly accurate two-spinor fully relativistic solution of the two-center Coulomb problem utilizing the finite-element method (FEM) and furthermore developed a relativistic minimax two-spinor linear combination of atomic orbitals (LCAO). In the present paper the authors present Dirac-Fock-Slater (DFS-) density functional calculations for two-atomic molecules up to super heavy systems using the fully nonlinear minimax FEM and the minimax LCAO in its linearized approximation (linear approximation to relativistic minimax). The FEM gives highly accurate benchmark results for the DFS functional. Especially considering molecules with up to super heavy atoms such as UubO and Rg2, the authors found that LCAO fails to give the correct systematic trends. The accurate FEM results shed a new light on the quality of the DFS-density functional.
在先前的工作中，作者利用有限元方法（FEM）给出了双中心库仑问题的一个高精度双旋量全相对论解，并且进一步发展了相对论极小极大双旋量原子轨道线性组合（LCAO）。在本文中，作者使用全非线性极小极大有限元方法以及线性化近似（相对论极小极大的线性近似）下的极小极大原子轨道线性组合，给出了直至超重体系的双原子分子的狄拉克 - 福克 - 斯莱特（DFS -）密度泛函计算。有限元方法为DFS泛函给出了高精度的基准结果。特别考虑到诸如UubO和Rg₂等含有超重原子的分子，作者发现原子轨道线性组合无法给出正确的系统趋势。精确的有限元结果为DFS密度泛函的质量提供了新的见解。
