ime-dependent multiconfiguration self-consistent-field method based on occupation restricted multiple active space model for multielectron dynamics in intense laser fields
ime-dependent multiconfiguration self-consistent-field method based on occupation restricted multiple active space model for multielectron dynamics in intense laser fields
复制标题
强激光场多电子动力学中基于占据限制多活动空间模型的时间相关多构型自洽场方法
DOI：
10.1103/physreva.91.023417
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
T. Sato and K. L. Ishikawa
中科院分区：
文献类型：
--
作者：
A. Tada;N. Namekata;and S. Inoue;T. Sato and K. L. Ishikawa
针对强激光场中的多电子动力学，提出了基于占用限制多活动空间模型的瞬态多配置自洽场方法（TD-ORMAS）。扩展先前提出的时间相关的完整活动空间自洽场方法[TD-CASSCF；物理。 Rev. A 88, 023402 (2013)PLRAAN1050-294710.1103/PhysRevA.88.023402]，将占据轨道分为核心轨道和活性轨道，TD-ORMAS方法进一步将活性轨道细分为任意数量的子群，并通过给出分布在每个子群中的最小和最大电子数来提出占据限制子组。这使得构型相互作用（CI）空间的构建变得高度灵活，从而允许动态的大活动空间模拟，例如核心激发或电离。基于时间相关变分原理推导了CI系数和空间轨道的运动方程，并提出了一种有效的算法来求解轨道时间导数。以易于编程的方式给出了计算实现的深入描述。一维氢化锂团簇模型的数值应用表明，TD-ORMAS 框架的高度灵活性允许通过利用 TD-CASSCF 方法的系统系列逼近来经济高效地模拟多电子动力学。
The time-dependent multiconfiguration self-consistent-field method based on the occupation-restricted multiple-active-space model is proposed (TD-ORMAS) for multielectron dynamics in intense laser fields. Extending the previously proposed time-dependent complete-active-space self-consistent-field method [TD-CASSCF; Phys. Rev. A 88, 023402 (2013)PLRAAN1050-294710.1103/PhysRevA.88.023402], which divides the occupied orbitals into core and active orbitals, the TD-ORMAS methodfurthersubdivides the active orbitals into an arbitrary number of subgroups and poses theoccupation restrictionby giving the minimum and maximum number of electrons distributed in each subgroup. This enables highly flexible construction of the configuration-interaction (CI) space, allowing a large-active-space simulation of dynamics, e.g., the core excitation or ionization. The equations of motion for both CI coefficients and spatial orbitals are derived based on the time-dependent variational principle, and an efficient algorithm is proposed to solve for the orbital time derivatives. In-depth descriptions of the computational implementation are given in a readily programmable manner. The numerical application to the one-dimensional lithium hydride cluster models demonstrates that the high flexibility of the TD-ORMAS framework allows for the cost-effective simulations of multielectron dynamics by exploiting systematic series of approximations to the TD-CASSCF method.