在CP2K和OpenMolcas中实现结密度嵌入:CASSCF波函数嵌入高斯波和平面波DFT环境中
Lukas Schreder1, Sandra Luber1
1University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
The Journal of chemical physics
|October 10, 2024
概括
本研究引入了一种新的计算方法,将密度函数理论 (DFT) 和波函数 (WF) 方法结合起来,用于准确的化学反应建模. 该方法平衡了计算成本和准确性,使复杂分子系统的详细研究成为可能.
科学领域:
- 计算化学计算化学
- 量子力学就是量子力学.
- 材料科学 材料科学 材料科学
背景情况:
- 化学过程通常涉及局部分子轨道和共价键重组.
- 密度函数理论 (DFT) 可能不足以准确地建模这些局部反应.
- 相关波函数 (WF) 方法提供更高的准确性,但在计算上昂贵.
研究的目的:
- 开发一种集成的计算方法,用于研究大型系统内的局部化学反应.
- 为了在没有高昂的计算成本的情况下,在本地范围内准确地建模化学过程.
- 为量子嵌入提供结合DFT和WF方法的无工作流.
主要方法:
- 基于结密度嵌入的结解算法的实现.
- 在DFT环境中嵌入完整的活动空间自我一致场 (CASSCF) 模拟.
- 在没有外部依赖的情况下集成OpenMolcas和CP2K代码.
- 在环境-子系统对上测试方法.
主要成果:
- 在使用OpenMolcas和CP2K的DFT环境中成功嵌入CASSCF (WF方法).
- 证明WF精度和DFT效率之间的平衡计算成本.
- 在模型系统上验证方法.
结论:
- 开发的方法为研究局部化学反应提供了一种准确且计算效率高的方法.
- 这种方法有助于研究复杂的化学系统,例如与表面相互作用的分子.
- 不同计算方法的无集成为理论化学研究开辟了新的途径.
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