Ground-state energy and spin gap of spin-12 Kagomé-Heisenberg antiferromagnetic clusters: Large-scale exact diagonalization results

We present a comprehensive list of the ground-state energies and the spin gaps of finite Kagomé clusters with up to 42 spins obtained using large-scale exact diagonalization techniques. This represents the current limit of this exact approach. For a fixed number of spins N, we study several cluster shapes under periodic boundary conditions in both directions resulting in a toroidal geometry. The clusters are characterized by their side length …