Fig. 1: Density of states at EF for 32 layered lanthanide materials.
From: Exploring two-dimensional van der Waals heavy-fermion material: Data mining theoretical approach

The open-core DFT calculations were performed to check non-f contribution at EF. Materials can be classified into three different groups; insulating (squares), conduction bands (CB) from La d orbitals (triangles), and conduction bands from ligand atoms (circles). Open and filled symbols represent the materials having empty (or fully occupied) 4f orbitals and partially filled 4f orbitals, respectively.