对准确的无相辅助场量子蒙特卡罗在3D过渡金属复合体上的多配置试验的评估
Hung T Vuong1, Ankit Mahajan1, John L Weber2
1Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, United States.
Journal of chemical theory and computation
|March 3, 2026
概括
我们评估了过渡金属系统中无相辅助场量子蒙特卡罗 (ph-AFQMC) 的试验波函数协议. 在ph-AFQMC的配置相互作用单双 (CISD) 试验状态中,实现了对电离潜力的最高精度.
科学领域:
- 量子化学是一种量子化学.
- 计算物理学的计算物理.
- 材料科学是一种材料科学.
背景情况:
- 对过渡金属系统的电子性质的准确预测至关重要.
- 无相辅助场量子蒙特卡罗 (ph-AFQMC) 为高精度计算提供了一个有前途的方法.
- 评估不同的试验波函数协议对于优化ph-AFQMC性能至关重要.
研究的目的:
- 评估在过渡金属系统上的ph-AFQMC的多配置试验波函数协议.
- 对实验和高精度计算数据进行垂直电离潜力 (VIP) 的基准测试.
- 为这些系统确定最准确和最具成本效益的ph-AFQMC协议.
主要方法:
- 基准测试ph-AFQMC与各种试验波函数 (包括CISD) 对于过渡金属复合物的VIP.
- 与结合集群理论方法 (CCSD) 和DLPNO-CCSD (T1) 的比较.
- 通过使用不同的方案,对完全基数 (CBS) 极限进行推断.
主要成果:
- 具有CISD试验状态的ph-AFQMC显示了与实验电离潜力 (<2 kcal/mol误差) 最接近的一致性.
- 通过将ph-AFQMC与三次ζ基结合,以及DLPNO-CCSD(T1) CBS校正,以适度的计算成本提供了良好的准确性.
- 系统地分析了不同试验状态和基准集的性能.
结论:
- 在ph-AFQMC中的CISD试验状态对于过渡金属系统中的电离潜能非常准确,尽管具有可扩展性的限制.
- 优化的ph-AFQMC协议,结合CBS推断,可以在具有挑战性的系统中实现接近实验的准确性.
- 这项工作为选择适合过渡金属化学的计算方法提供了宝贵的见解.
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