Calculating the ground state energy of a molecule efficiently is of great interest in quantum chemistry. The exact numerical solution of the electronic Schrodinger equation remains unfeasible for most molecules requiring approximate methods at best. In this paper we introduce the use of Quantum Community Detection performed using the D-Wave quantum annealer to reduce the molecular Hamiltonian matrix without chemical knowledge. Given a molecule represented by a matrix of Slater determinants, the connectivity between Slater determinants is viewed as a graph adjacency matrix for determining multiple communities based on modularity maximization. The resulting lowest energy cluster of Slater determinants is used to calculate the ground state energy within chemical accuracy. The details of this method are described along with demonstrating its performance across multiple molecules of interest and a bond dissociation example. This approach is general and can be used as part of electronic structure calculations to reduce the computation required.

中文翻译：

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使用量子社区检测向下折叠分子哈密顿矩阵

有效地计算分子的基态能量在量子化学中非常重要。对于大多数需要近似方法的分子，电子薛定inger方程的精确数值解仍然不可行。在本文中，我们介绍了使用通过D-Wave量子退火仪进行的量子社区检测来减少分子哈密顿矩阵的过程，而无需了解化学知识。给定一个由Slater行列式矩阵表示的分子，Slater行列式之间的连通性被视为图邻域矩阵，用于基于模块化最大化确定多个社区。最终得出的Slater行列式能量簇用于计算化学精度范围内的基态能量。描述了该方法的细节，并演示了该方法在多个目标分子上的性能以及键解离的例子。这种方法很通用，可以用作电子结构计算的一部分，以减少所需的计算。