Development of a Minimal Auxiliary Basis for the Particle--Particle Random Phase Approximation (ppRPA): Accelerating Excited-State Calculations in Diradical Nanoparticles and Periodic Systems

Yuchen Wang, Zhenyu Li

Singlet--triplet gaps set the energy scale of the two-spin manifold in molecular quantum information materials, and such systems frequently carry diradical character: metal nanoclu…