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Updated: Jun 13, 2025

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局部化活动空间方法与单元选择性合集群

Abhishek Mitra¹, Ruhee D'Cunha¹, Qiaohong Wang²

¹Department of Chemistry, Chicago Center for Theoretical Chemistry, University of Chicago, Chicago, Illinois 60637, United States.

Journal of chemical theory and computation

|September 10, 2024

概括

我们开发了一个新的量子算法,局部化的活跃空间单元选择性合集群单双 (LAS-USCCSD),以改进量子化学计算. 这种方法显著减少了计算资源,使复杂的模拟在当前量子硬件上更可行.

科学领域:

量子计算是一种量子计算.
计算化学计算化学
理论化学理论化学

背景情况:

准确的量子化学计算对于理解分子行为至关重要.
混合量子-经典算法为解决复杂的化学问题提供了一个有希望的方法.
短期量子计算机需要高效的算法来克服量子比特数量和连贯时间的限制.

研究的目的:

引入和评估本地化活动空间单元选择性合集群单双 (LAS-USCCSD) 方法.
评估LAS-USCCSD在减少量子化学模拟的计算成本方面的效率.
为了证明LAS-USCCSD用于计算分子性质和磁性合常数的适用性.

主要方法:

开发了LAS-USCCSD混合量子-经典算法.
经典的局部化活动空间自相一致场 (LASSCF) 计算.
选择性识别关键的集群幅度,用于变量量子自溶器 (VQE) 实现.
与本地化活动空间单元合集群 (LAS-UCCSD) 方法进行基准测试.

主要成果:

LAS-USCCSD 显著减少了至少一个数量级的所需参数数量.
该方法在计算 (H2) 2, (H2) 4 和跨-丁等系统的总能量时,达到与LAS-UCCSD相当的准确性.
证明了对双金属化合物[Cr2(OH) 3(NH3) 6) 3+的磁性合常数的准确计算.
观察到电路深度减少,这对近期量子硬件至关重要.

结论:

拉斯-USCCSD为多参考量子化学计算提供了一种更有效的方法.
该算法的减少参数和电路深度的能力对于在杂的中级量子 (NISQ) 设备上进行实际实施至关重要.
这项工作为化学和材料科学中更容易获得和更准确的量子模拟铺平了道路.

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