A new global interaction potential for the CH4 and N-2 complex has been derived at the MP2 level of theory and correlation consistent basis sets. The potential energy surface has been computed on a large grid of molecular geometries. In the most stable conformation, the nitrogen is below the methane pyramid base while the N-N bond axes and one of the methane C-H bonds are coplanar. The complete basis set limit of the interaction energies have been fitted to well-known analytical functions. Then the second virial coefficients were calculated for fitted potentials which agrees well with the experimental values. (c) 2008 Elsevier B. V. All rights reserved.