电子轨道的经济准牛顿单元优化
Samuel A Slattery1, Kshitijkumar A Surjuse1, Charles C Peterson2
1Department of Chemistry, Virginia Tech, Blacksburg, VA 24061, USA. efv@vt.edu.
Physical chemistry chemical physics : PCCP
|February 8, 2024
概括
我们开发了一种新的计算方法,即准牛顿单元优化与信任区域 (QUOTR) 解析器,以有效优化分子轨道. 这种方法显著降低了量子化学计算的计算成本.
科学领域:
- 计算化学是一种计算化学.
- 量子力学就是量子力学.
- 电子结构理论 电子结构理论
背景情况:
- 准确的电子结构计算对于理解分子性质至关重要.
- 像Roothaan-Hall这样的传统方法可能是计算密集型的.
- 对直角轨道的优化是中场电子结构方法的一个关键挑战.
研究的目的:
- 为了展示一个高效的准牛顿轨道解决器,QUOTR.
- 为了减少轨道优化中梯度评估和计算成本的数量.
- 将QUOTR的性能与现有方法进行比较.
主要方法:
- 开发了一个名为Quasi-Newton Unitary Optimization with Trust-Region (QUOTR) 的新型解决方案.
- 使用具有有限内存的布劳登-弗莱彻-戈德法尔布-沙诺 (L-BFGS) 算法,具有信任区域限制.
- 利用L-BFGS的低级结构,以提高效率.
- 应用单元旋转来实现直角轨道优化.
主要成果:
- QUOTR在优化直角轨道方面表现出了效率.
- 与标准方法相比,解决器减少了计算步骤.
- 性能与Roothaan-Hall使用DIIS和其他牛顿解决器进行了基准测试.
结论:
- QUOTR为中场电子结构计算提供了一个计算效率高的替代方案.
- 该方法显示了加速哈特里-福克和科恩-沙姆计算的前景.
- 对于轨道优化,L-BFGS算法和信任区域策略是有效的.
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