论文标题
使用Koopmans定理构建基集：以紧凑的高斯基础接近锂的高rydberg激发态
Using Koopmans' theorem for constructing basis sets: Approaching high Rydberg excited states of lithium with a compact Gaussian basis
论文作者
论文摘要
为了从头开始描述Rydberg激发态的准确描述，该研究表明，通过对相应离子核的虚拟轨道的廉价优化来生成适当的弥散基函数。通过遵循这种方法，可以在EOM-CCSD的理论水平紧凑，最多是国家选择性合同的高斯基础基集，可以获得数十个融合相关的锂rydberg国家，即最高24S，25p，14d，16f和16g的所有状态，尚未通过其他依从性方法获得。尽管具有较小的尺寸和高斯的特征，但优化的基础仍导致高度准确的激发能，这些激发能仅在MEV的顺序上与参考最新的最先进的高斯方法明确相关的高斯方法，甚至通过SLATER通过大量顺序超过全CI结果。
For accurate ab initio description of Rydberg excited states the study suggests generating the appropriate diffuse basis functions by a cheap variational optimization of virtual orbitals of the corresponding ion core. By following this approach, dozens of converged correlated lithium Rydberg states, namely all the states up to 24S, 25P, 14D, 16F and 16G, not yet achieved by other ab initio approaches, could be obtained at the EOM-CCSD level of theory with compact and mostly state-selective contracted Gaussian basis sets. Despite its small size and Gaussian character, the optimized basis leads to highly accurate excitation energies that differ merely in the order of meV from the reference state-of-the-art explicitly correlated Gaussian method and even surpass Full-CI results on Slater basis by an order of magnitude.
