  We have investigated the effect of unconventional pairing mechanism in MgB2
using a two-band model within the framework of Bogoliubov-Valatin formalism.
The approach incorporates the intra- band s-wave interaction in the s- and
p-bands, as well as interband s-wave interaction between them. The analysis
assumes the pairing interaction matrix comprises of attractive electron-phonon,
charge fluctuation and repulsive electron-electron (Coulomb) interactions to
account for superconductivity in MgB2. The model is used to estimate the
transition temperature and isotope effect exponent as well as to elucidate the
importance of interband contributions in the superconductivity of the system.
