Orbital magnetic susceptibility of graphene and MoS2

We calculate the orbital magnetic susceptibility chi(orb) for an 8-band tight-binding model of gapless and gapped graphene using Green's functions. Analogously, we study chi(orb) for a MoS2 12-band model. For both materials, we unravel the character of the processes involved in the magnetic response by looking at the contribution at each point of the Brillouin zone. By this, a clear distinction between intra- and interband excitations is generally possible and we are able to predict qualitative features of chi(orb) only through the knowledge of the band structure. The study is complemented by comparing the magnetic response with that of 2-band lattice Hamiltonians which reduce to the Dirac and Bernevig-Hughes-Zhang models in the continuum limit.