  Magnetic and thermodynamical properties of a system of spins in a honeycomb
lattice, such as magnetization, magnetic susceptibility and specific heat, in a
low-temperature regime are investigated by considering the effects of a
Kekul\'e scalar exchange and QED vacuum polarization corrections to the
interparticle potential. The spin lattice calculations are carried out by means
of Monte Carlo simulations. We present a number of comparative plots of all the
physical quantities we have considered and a detailed analysis is presented to
illustrate the main features and the variation profiles of the properties with
the applied external magnetic field and temperature.
