  We have performed first principles total energy calculations to investigate
the structural and reactivity parameters of novel N12X12H12 (X=B, Al, Ga, In,
TI) nitrides, in their coronene-like (C24H12) structure to simulate these
sheets. The exchange and correlations potential energies are treated in the
generalized gradient approximation (GGA), and the local density approximation
within the parameterization of Perdew-Wang and Perdew-Burke-Ernzerhof (PWC,
PBE) and the doubly polarized atomic base (DNP). The chemical potential,
hardness and electrophilicy index, as well as bond length are reported. The
bond length of the structures is similar to the bulk. The gap between the HOMO
and LUMO decreases from BN (5.18eV) to TlN (1.76 eV). At the same time, the
polarity increases except for TlN.
