Interdisciplinary Center for Scientific Computing, Heidelberg University, Im Neuenheimer Feld 205, D-69120 Heidelberg, Germany.
Laboratory of Quantum Chemistry, Irkutsk State University, Karl Marx Street 1, 664003 Irkutsk, Russia.
J Chem Phys. 2021 Mar 14;154(10):104117. doi: 10.1063/5.0043337.
Computational schemes for comprehensive studies of molecular electron-attached states and the calculation of electron affinities (EAs) are formulated and implemented employing the intermediate state representation (ISR) formalism and the algebraic-diagrammatic construction approximation for the electron propagator (EA-ADC). These EA-ADC(n)/ISR(m) schemes allow for a consistent treatment of not only electron affinities and pole strengths up to third-order of perturbation theory (n = 3) but also one-electron properties of electron-attached states up to second order (m = 2). The EA-ADC/ISR equations were implemented in the Q-Chem program for Ŝ-adapted intermediate states, allowing also open-shell systems to be studied using unrestricted Hartree-Fock references. For benchmarking of the EA-(U)ADC/ISR schemes, EAs and dipole moments of various electron-attached states of small closed- and open-shell molecules were computed and compared to full configuration interaction data. As an illustrative example, EA-ADC(3)/ISR(2) has been applied to the thymine-thymine (6-4) DNA photolesion.
计算方案为综合研究分子电子附加态和电子亲和能 (EAs) 的计算制定和实施采用中间状态表示 (ISR) 形式和电子传播子的代数图论构造逼近 (EA-ADC)。这些 EA-ADC(n)/ISR(m) 方案不仅允许一致地处理电子亲和能和直到三阶微扰理论的极点强度 (n = 3)，还允许电子附加态的单电子性质达到二阶 (m = 2)。EA-ADC/ISR 方程在 Q-Chem 程序中针对 Ŝ 适应的中间状态进行了实现，也允许使用非限制哈特利-福克参考来研究开壳系统。为了对 EA-(U)ADC/ISR 方案进行基准测试，计算了各种小闭壳和开壳分子的电子附加态的电子亲和能和偶极矩，并与全组态相互作用数据进行了比较。作为一个说明性的例子，EA-ADC(3)/ISR(2) 已应用于胸腺嘧啶-胸腺嘧啶 (6-4) DNA 光损伤。
