Quantum Package 2.0: An Open-Source Determinant-Driven Suite of Programs
Quantum Package 2.0: An Open-Source Determinant-Driven Suite of Programs
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DOI：
10.1021/acs.jctc.9b00176
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发表时间：
2019-06-01
影响因子：
5.5
通讯作者：
Scemama, Anthony
中科院分区：
文献类型：
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作者：
Garniron, Yann;Applencourt, Thomas;Scemama, Anthony
量子化学是一门严重依赖于非常昂贵的数值计算的学科。相关波函数方法的标度在它们的标准实现中在O（N-5）和O（e（N））之间，其中N与系统大小成比例。因此，在化学上有意义的系统上执行精确计算需要（i）可以降低计算缩放的近似值和（ii）利用现代大规模并行架构的有效实现。QUANTUM PACKAGE是一个专门为波函数方法设计的量子化学开源编程环境。其主要目标是发展决定子驱动的选择组态相互作用（sCI）方法和多参考二阶微扰理论（PT 2）。决定因素驱动的框架允许程序员在参考空间中包含任意一组决定因素，从而提供更大的方法自由。在量子包中实现的sCI方法基于CIPSI（使用迭代进行的扰动选择的配置交互）算法，该算法用PT 2校正补充变分sCI能量。最近增加了额外的外部插件来执行多参考耦合簇理论和距离分离密度泛函理论的计算。所有程序都是使用IRPF 90代码生成器开发的，这简化了协作工作和新功能的开发。QUANTUM PACKAGE致力于简化新方法的实现和实验，同时在现代超级计算机架构上尽可能简单高效地进行并行计算。目前，该代码使，例行，实现运行在大约2 000个CPU核心，在参考空间中的数以千万计的决定因素。此外，我们已经能够推动多达12 288个核心，以测试其并行效率。在本手稿中，我们还介绍了一些关键的新发展：（i）重正化二阶微扰校正有效外推到全CI限制和（ii）随机版本的CIPSI选择同时进行的PT 2计算，没有额外的成本。
Quantum chemistry is a discipline which relies heavily on very expensive numerical computations. The scaling of correlated wave function methods lies, in their standard implementation, between O(N-5) and O(e(N)), where N is proportional to the system size. Therefore, performing accurate calculations on chemically meaningful systems requires (i) approximations that can lower the computational scaling and (ii) efficient implementations that take advantage of modern massively parallel architectures. QUANTUM PACKAGE is an open-source programming environment for quantum chemistry specially designed for wave function methods. Its main goal is the development of determinant-driven selected configuration interaction (sCI) methods and multireference second-order perturbation theory (PT2). The determinant-driven framework allows the programmer to include any arbitrary set of determinants in the reference space, hence providing greater methodological freedom. The sCI method implemented in QUANTUM PACKAGE is based on the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) algorithm which complements the variational sCI energy with a PT2 correction. Additional external plugins have been recently added to perform calculations with multireference coupled cluster theory and range-separated density-functional theory. All the programs are developed with the IRPF90 code generator, which simplifies collaborative work and the development of new features. QUANTUM PACKAGE strives to allow easy implementation and experimentation of new methods, while making parallel computation as simple and efficient as possible on modern supercomputer architectures. Currently, the code enables, routinely, to realize runs on roughly 2 000 CPU cores, with tens of millions of determinants in the reference space. Moreover, we have been able to push up to 12 288 cores in order to test its parallel efficiency. In the present manuscript, we also introduce some key new developments: (i) a renormalized second-order perturbative correction for efficient extrapolation to the full CI limit and (ii) a stochastic version of the CIPSI selection performed simultaneously to the PT2 calculation at no extra cost.