Jensen Phillip W K, Kjellgren Erik Rosendahl, Reinholdt Peter, Ziems Karl Michael, Coriani Sonia, Kongsted Jacob, Sauer Stephan P A
Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark.
Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark.
J Chem Theory Comput. 2024 May 14;20(9):3613-3625. doi: 10.1021/acs.jctc.4c00069. Epub 2024 May 3.
Determining the properties of molecules and materials is one of the premier applications of quantum computing. A major question in the field is how to use imperfect near-term quantum computers to solve problems of practical value. Inspired by the recently developed variants of the quantum counterpart of the equation-of-motion (qEOM) approach and the orbital-optimized variational quantum eigensolver (oo-VQE), we present a quantum algorithm (oo-VQE-qEOM) for the calculation of molecular properties by computing expectation values on a quantum computer. We perform noise-free quantum simulations of BeH in the series of STO-3G/6-31G/6-31G* basis sets and of H and HO in 6-31G using an active space of four electrons and four spatial orbitals (8 qubits) to evaluate excitation energies, electronic absorption, and, for twisted H, circular dichroism spectra. We demonstrate that the proposed algorithm can reproduce the results of conventional classical CASSCF calculations for these molecular systems.
确定分子和材料的性质是量子计算的主要应用之一。该领域的一个主要问题是如何使用不完美的近期量子计算机来解决具有实际价值的问题。受最近开发的运动方程量子对应方法（qEOM）和轨道优化变分量子本征求解器（oo-VQE）变体的启发，我们提出了一种量子算法（oo-VQE-qEOM），用于通过在量子计算机上计算期望值来计算分子性质。我们使用四个电子和四个空间轨道（8个量子比特）的活性空间，在STO-3G/6-31G/6-31G*基组系列中对BeH以及在6-31G中对H和HO进行无噪声量子模拟，以评估激发能、电子吸收，以及对于扭曲的H的圆二色光谱。我们证明，所提出的算法可以重现这些分子系统的传统经典CASSCF计算结果。
