Potential energy function and spectrum of the NO ground state

The dissociation limit of NO is correctly determined based on group theory and atomic and molecular statics. The equilibrium geometries of the ground state of NO are calculated by a variety of methods and basis sets different combination. Compared with the experimental value,the CCSD( T) /6- 311 + + G( 3d2f) are selected to scan the potential energy curves of the ground state. Dissociation energy,force constants f2,f3(,f)4and spectroscopic constants ωe,ωeχe,Be(,a)eof this state are obtained by least square fitting to the Murrell-Sorbie function. It is showed that the results of CCSD( T) /6- 311 + + G( 3d2f) are in good agreement with the experimental data.