Off-diagonal derivative discontinuities in the reduced density matrices of electronic systems.
Off-diagonal derivative discontinuities in the reduced density matrices of electronic systems.
复制标题
电子系统降密度矩阵中的非对角导数不连续性。
DOI：
10.1063/5.0023955
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
J. Cioslowski
中科院分区：
文献类型：
--
作者：
J. Cioslowski
一个显式的表达式有关的第五阶非对角尖点的大小在真实的部分的单电子约化密度矩阵的"上顶部"的两个电子的密度推导出在一个严格的方式从电子-电子聚结的基础电子波函数的行为。这个尖点的存在对量子化学和固态物理的电子结构计算的影响，包括对它们的准确性施加的限制，阐明。特别地，对于由任意偶数个电子组成的系统的1S态，证明了自然轨道占据数的幂律衰减。本文简要讨论了多电子约化密度矩阵中类非对角尖点的实际意义。
An explicit expression relating the magnitude of the fifth-order off-diagonal cusp in the real part of the one-electron reduced density matrix to the "on-top" two-electron density is derived in a rigorous manner from the behavior of the underlying electronic wavefunction at the electron-electron coalescence. The implications of the presence of this cusp upon electronic structure calculations of quantum chemistry and solid-state physics, including the limits imposed upon their accuracy, are elucidated. In particular, the power-law decay of the occupation numbers of the natural orbitals is demonstrated for 1S states of systems composed of arbitrary even numbers of electrons. The practical importance of analogous off-diagonal cusps in many-electron reduced density matrices is briefly discussed.