20 papers
Analytical Nuclear Gradients and Hessians on Quantum Hardware via Orbital-Optimized VQE with Error Mitigation
Renato Olarte Hernandez, Karl Michael Ziems, Erik Kjellgren +3
Nuclear gradients and Hessians are fundamental quantities in computational chemistry, essential for a wide range of applications including geometry optimization, vibrational spectr…
Second-Order Magnetic Properties in Paramagnetic Molecules From a Current Density Formulation Including Scalar Relativistic Effects
Francesco Ferdinando Summa, Sonia Coriani, Andre Severo Pereira Gomes
This work presents the theoretical background for the computation of nuclear magnetic shielding and magnetizability tensors of paramagnetic molecules, using a magnetically induced…
Resource-efficient energy-based operator selection in fermionic ADAPT-VQE via exact Hamiltonian transformation
Emanuele Rossi, Erik Rosendahl Kjellgren, Artur F. Izmaylov +3
The energy-based approach to operator selection in ADAPT-VQE relies on reconstructing the one-parameter energy landscape for each operator in the pool. In fermionic implementations…
Orbital-optimized spin-adapted multistate contracted VQE for excited states and properties on quantum hardware
Erik Rosendahl Kjellgren, Karl Michael Ziems, Peter Reinholdt +3
We introduce the orbital-optimized multistate contracted variational quantum eigensolver (oo-MC-VQE) method with spin-adapted operators for the computation of ground and excited st…
Velocity Formulations for Hyper-Rayleigh Scattering Optical Activity Spectroscopy: Addressing the Origin-dependence Problem
Andrea Bonvicini, Sonia Coriani, Benoît Champagne
The theory of hyper-Rayleigh scattering optical activity (HRS-OA) spectroscopy has previously been described within the length formulation of the pure electric-dipole and mixed (el…
A Lanczos-based algorithm for sum-over-states calculations of NMR spin--spin coupling constants at the RPA level of theory: The Fermi-contact term
Sarah L. V. Zahn, Luna Zamok, Sonia Coriani +1
The analysis of nuclear magnetic resonance parameters, such as the indirect nuclear spin-spin coupling constants, in terms of contributions from localised molecular orbitals is a c…