Quantum Simulations of Chemical Reactions: Achieving Accuracy with NISQ Devices

Abstract

Quantum computing is viewed as a promising technology because of its potential for polynomial growth in complexity, in contrast to the exponential growth observed in its classical counterparts. In the current Noisy Intermediate-Scale Quantum (NISQ) era, the Variational Quantum Eigensolver (VQE), a hybrid variational algorithm, is utilized to simulate molecules using qubits and calculate molecular properties. However, simulating a chemical reaction to compute the reaction energy using VQE algorithm has not yet reached chemical accuracy relative to the benchmark computational chemistry methods due to limitations such as the number of qubits, circuit depth, and noise introduced within the model. To address this issue, we propose the definition of different active spaces for studying chemical reactions, incorporating irreducible representations of both the ground and excited states of the molecules. Our results demonstrate that this approach achieves chemical accuracy in predicting the reaction energy for various reactions. For all reactions studied, the difference in reaction energies between conventional computational chemistry methods and the quantum-classical hybrid VQE algorithm is less than 1 kcal/mol. Furthermore, our analysis simplifies the process of selecting active spaces and electrons for each reaction, reducing it to a single optimal combination that ensures the chemical accuracy for each reaction.

References in corpus (22)

• Quantum Computing in the NISQ era and beyond
• A variational eigenvalue solver on a quantum processor
• Hardware-efficient Variational Quantum Eigensolver for Small Molecules and Quantum Magnets
• Simulated Quantum Computation of Molecular Energies
• Recent developments in the PySCF program package
• Parameterized quantum circuits as machine learning models
• An adaptive variational algorithm for exact molecular simulations on a quantum computer
• Simulation of Electronic Structure Hamiltonians Using Quantum Computers
• Generalized Unitary Coupled Cluster Wavefunctions for Quantum Computation
• qubit-ADAPT-VQE: An adaptive algorithm for constructing hardware-efficient ansatze on a quantum processor
• Automated Selection of Active Orbital Spaces
• Is there evidence for exponential quantum advantage in quantum chemistry?
• Structure optimization for parameterized quantum circuits
• Tapering off qubits to simulate fermionic Hamiltonians
• Is the Trotterized UCCSD Ansatz chemically well-defined?
• Reducing qubit requirements for quantum simulation using molecular point group symmetries
• A state-averaged orbital-optimized hybrid quantum-classical algorithm for a democratic description of ground and excited states
• Towards a Larger Molecular Simulation on the Quantum Computer: Up to 28 Qubits Systems Accelerated by Point Group Symmetry
• Benchmarking of Different Optimizers in the Variational Quantum Algorithms for Applications in Quantum Chemistry
• Simulation of a Diels-Alder Reaction on a Quantum Computer
• Factorized Quadruples and a Predictor of Higher-Level Correlation in Thermochemistry
• Study of Adaptative Derivative-Assemble Pseudo-Trotter Ansatzes in VQE through qiskit API