Conventional magnetization is originated from the half filled d or f orbitals of rare earth and transition elements. Resent observation of p orbital magnetization in two normal" GGA-PBE approximation . The results show the lower energy and non-magnetic state of the nitrogen terminated films and the higher energy and magnetic state of the calcium terminated films. We calculate the energy barrier between these two systems by using Nudged Elastic Band method and argue that both systems are unstable and relax to a rock-salt CaN film on silicon, which is nonmagnetic.