DINITROGEN SULFIDE (N2S) AND ITS PROTONATED ISOMERS

The protonation of N2S offers a way of examining the nature of this simple, recently synthesized molecule. The conventional linear NNS, the less conventional NSN, and cyclic structures have been investigated with ab initio molecular quantum mechanical methods. Double-zeta plus polarization (DZP) and triple-zeta plus double polarization (TZ2P) basis sets have been used in conjugation with self-consistent-field (SCF), single and double excitation configuration interaction (CISD), and coupled cluster (CCSD) methods. The parent N2S potential energy hypersurface is rather complicated, but for the protonated system no isomer lies within 30 kcal/mol of the NNSH+ global minimum.