Journal of Chemical Physics, Vol.113, No.14, 5644-5652, 2000
Renormalized CCSD(T) and CCSD(TQ) approaches: Dissociation of the N-2 triple bond
The recently proposed renormalized and completely renormalized CCSD(T) and CCSD(TQ) methods, which can be viewed as generalizations of the noniterative perturbative CCSD(T) and CCSD(TQ(f)) schemes and which result from the more general method of moments of coupled-cluster equations, are applied to the dissociation of the ground-state N-2 molecule. It is shown that the renormalized and completely renormalized CCSD(T) and CCSD(TQ) methods provide significantly better results for large N-N separations than their unrenormalized CCSD(T) and CCSD(TQ(f)) counterparts.