Computational analysis of chemical reactions using a variational quantum eigensolver algorithm without specifying spin multiplicity

• URL: http://arxiv.org/abs/2303.05065v2
• Date: Mon, 13 Mar 2023 04:54:26 GMT
• Title: Computational analysis of chemical reactions using a variational quantum eigensolver algorithm without specifying spin multiplicity
• Authors: Soichi Shirai, Hokuto Iwakiri, Keita Kanno, Takahiro Horiba, Keita Omiya, Hirotoshi Hirai and Sho Koh
• Abstract summary: Ground state potential energy curves for PtCO were calculated as a proof-of-concept using a variational quantum eigensolver algorithm. Quantum computing can be a powerful tool for the analysis of the chemical reactions of systems for which the spin multiplicity of the ground state and variations in this parameter are not known in advance.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: The analysis of a chemical reaction along the ground state potential energy surface in conjunction with an unknown spin state is challenging because electronic states must be separately computed several times using different spin multiplicities to find the lowest energy state. However, in principle, the ground state could be obtained with just a single calculation using a quantum computer without specifying the spin multiplicity in advance. In the present work, ground state potential energy curves for PtCO were calculated as a proof-of-concept using a variational quantum eigensolver (VQE) algorithm. This system exhibits a singlet-triplet crossover as a consequence of the interaction between Pt and CO. VQE calculations using a statevector simulator were found to converge to a singlet state in the bonding region, while a triplet state was obtained at the dissociation limit. Calculations performed using an actual quantum device provided potential energies within $\pm$2 kcal/mol of the simulated energies after adopting error mitigation techniques. The spin multiplicities in the bonding and dissociation regions could be clearly distinguished even in the case of a small number of shots. The results of this study suggest that quantum computing can be a powerful tool for the analysis of the chemical reactions of systems for which the spin multiplicity of the ground state and variations in this parameter are not known in advance.

Related papers

• Folded Spectrum VQE : A quantum computing method for the calculation of molecular excited states [0.0]
  Folded Spectrum (FS) method as extension to Variational Quantum Eigensolver (VQE) algorithm for computation of molecular excited states. Inspired by the variance-based methods from the Quantum Monte Carlo literature, the FS method minimizes the energy variance, thus requiring a computationally expensive squared Hamiltonian. We apply the FS-VQE method to small molecules for a significant reduction of the computational cost.
  arXiv  Detail & Related papers  (2023-05-08T15:34:56Z)
• Quantum Eigenvector Continuation for Chemistry Applications [57.70351255180495]
  We show that a significant amount of (quantum) computational effort can be saved by making use of already calculated ground states. In all cases, we show that the PES can be captured using relatively few basis states.
  arXiv  Detail & Related papers  (2023-04-28T19:22:58Z)
• Calculating the many-body density of states on a digital quantum computer [58.720142291102135]
  We implement a quantum algorithm to perform an estimation of the density of states on a digital quantum computer. We use our algorithm to estimate the density of states of a non-integrable Hamiltonian on the Quantinuum H1-1 trapped ion chip for a controlled register of 18bits.
  arXiv  Detail & Related papers  (2023-03-23T17:46:28Z)
• Universality of critical dynamics with finite entanglement [68.8204255655161]
  We study how low-energy dynamics of quantum systems near criticality are modified by finite entanglement. Our result establishes the precise role played by entanglement in time-dependent critical phenomena.
  arXiv  Detail & Related papers  (2023-01-23T19:23:54Z)
• Equation-of-motion variational quantum eigensolver method for computing molecular excitation energies, ionization potentials, and electron affinities [4.21608910266125]
  Near-term quantum computers are expected to facilitate material and chemical research through accurate molecular simulations. We present an equation-of-motion-based method to compute excitation energies following the variational quantum eigensolver algorithm.
  arXiv  Detail & Related papers  (2022-06-21T16:21:04Z)
• Numerical Simulations of Noisy Quantum Circuits for Computational Chemistry [51.827942608832025]
  Near-term quantum computers can calculate the ground-state properties of small molecules. We show how the structure of the computational ansatz as well as the errors induced by device noise affect the calculation.
  arXiv  Detail & Related papers  (2021-12-31T16:33:10Z)
• Coarse grained intermolecular interactions on quantum processors [0.0]
  We develop a coarse-grained representation of the electronic response that is ideally suited for determining the ground state of weakly interacting molecules. We demonstrate our method on IBM superconducting quantum processors. We conclude that current-generation quantum hardware is capable of probing energies in this weakly bound but nevertheless chemically ubiquitous and biologically important regime.
  arXiv  Detail & Related papers  (2021-10-03T09:56:47Z)
• Computing molecular excited states on a D-Wave quantum annealer [52.5289706853773]
  We demonstrate the use of a D-Wave quantum annealer for the calculation of excited electronic states of molecular systems. These simulations play an important role in a number of areas, such as photovoltaics, semiconductor technology and nanoscience.
  arXiv  Detail & Related papers  (2021-07-01T01:02:17Z)
• Molecular Excited State Calculations with Adaptive Wavefunctions on a Quantum Eigensolver Emulation: Reducing Circuit Depth and Separating Spin States [0.0]
  Variational Quantum Deflation (VQD) is an extension of the Variational Quantum Eigensolver (VQE) for calculating electronic excited state energies. We investigate the use of adaptive quantum circuit growth (ADAPT-VQE) in excited state VQD calculations.
  arXiv  Detail & Related papers  (2021-05-21T10:59:29Z)
• Calculation of the ground-state Stark effect in small molecules using the variational quantum eigensolver [0.0]
  We study a quantum simulation for the hydrogen (H2) and lithium hydride (LiH) molecules, at an actual commercially available quantum computer, the IBM Q. Using the Variational Quantum Eigensolver (VQE) method, we study the molecule's ground state energy versus interatomic distance, under the action of stationary electric fields.
  arXiv  Detail & Related papers  (2021-03-22T11:49:42Z)
• Benchmarking adaptive variational quantum eigensolvers [63.277656713454284]
  We benchmark the accuracy of VQE and ADAPT-VQE to calculate the electronic ground states and potential energy curves. We find both methods provide good estimates of the energy and ground state. gradient-based optimization is more economical and delivers superior performance than analogous simulations carried out with gradient-frees.
  arXiv  Detail & Related papers  (2020-11-02T19:52:04Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.