Department of Chemistry, The University of Calgary, Calgary, Alberta T2N 1N4 Canada
Instituto dé Fisica e Química de São Carlos, Universidade de São Paulo, 13560 São Carlos, São Paulo Brazil
Abstract:
The relative stabilities and electronic structures of the linkage isomers NSO− and SNO− have been determined by the MNDO and ab initio Hartree—Fock—Slater methods. Both approaches predict a higher stability for SNO− by ca. 100 kcal mol−1, but an overlap population analysis indicates substantially higher bond orders for NSO− compared to SNO−. The calculations also reveal a low energy pathway with a barrier of ca. 6 kcal mol−1 for the isomerization process NSO− → SNO−. Good agreement was found between the observed UV-visible absorption bands for NSO− (λmax 379 nm) and SNO− (λmax 340 nm) and calculated values of the electronic transition energies.