Multireference Density Functional Theory for Describing Ground and Excited States with Renormalized Singles

Abstract

We applied renormalized singles (RS) in the multireference density functional theory (DFT) to calculate accurate energies of ground and excited states. The multireference DFT approach determines the total energy of the $N$-electron system as the sum of the ($N-2$)-electron energy from a density functional approximation (DFA) and the two-electron addition energies from the particle-particle Tamm-Dancoff approximation (ppTDA), naturally including multireference description. The ppTDA@RS-DFA approach uses the RS Hamiltonian capturing all singles contributions in calculating two-electron addition energies, and its total energy is optimized with the optimized effective potential method. It significantly improves the original ppTDA@DFA. For ground states, ppTDA@RS-DFA properly describes dissociation curves tested and the double bond rotation of ethylene. For excited states, ppTDA@RS-DFA provides accurate excitation energies and largely eliminates the DFA dependence. ppTDA@RS-DFA thus provides an efficient multireference approach to systems with static correlation.

References in corpus (4)

• Fractional spins and static correlation error in density functional theory
• Orbital Optimized Density Functional Theory for Electronic Excited States
• Renormalized Singles Green's Function in the T-Matrix Approximation for Accurate Quasiparticle Energy Calculation
• Comparing particle-particle and particle-hole channels of random-phase approximation

Cited by in corpus (8)

• Linear Scaling Calculations of Excitation Energies with Active-Space Particle-Particle Random Phase Approximation
• Accurate Excitation Energies of Point Defects from Fast Particle-Particle Random Approximation Calculations
• Combining Renormalized Singles $GW$ Methods with the Bethe-Salpeter Equation for Accurate Neutral Excitation Energies
• Renormalized Singles with Correlation in $GW$ Green's Function Theory for Accurate Quasiparticle Energies
• Accurate and Efficient Prediction of Double Excitation Energies Using the Particle-Particle Random Phase Approximation
• Energy-Specific Bethe-Salpeter Equation Implementation for Efficient Optical Spectrum Calculations
• Benchmarking the accuracy of the separable resolution of the identity approach for correlated methods in the numeric atom-centered orbitals framework
• LibppRPA: An Open-Source Library for Particle-Particle Random Phase Approximation