Multiconfigurational second-order perturbation study of the photochemical decomposition of methyl thionitrite

作者：Ruano Cristina; Otero Juan C; Arenas Juan F; Soto Juan^*

来源：Chemical Physics Letters, 2012, 553: 17-20.

DOI：10.1016/j.cplett.2012.09.060

The photodissociation of methyl thionitrite (CH3SNO) has been computationally studied by means of CAS-SCF and MS-CASPT2 methods. The analysis of the multiconfigurational wavefunction corroborates the assignments of the absorption spectra, the visible and UV bands assigned to S-0 , S-1(n, pi*) and S-0 -%26gt; S-2(pi, pi*) transitions correspond to 1A%26apos; -%26gt; 1A %26apos;%26apos;(n(sigma), pi*) and 1A%26apos; -%26gt; 2A%26apos;(n(pi), pi*) excitations, respectively. With respect to the photochemistry of CH3SNO, it is found that the potential energy surfaces associated with the low-lying excited states of this molecule (1(1)A %26apos;%26apos;, 2(1)A%26apos;, and 2(1)A %26apos;%26apos;) are repulsive along the NO elimination coordinates. For this reason, population of such excited states leads to NO extrusion as the primary process, in agreement with experiments.

• 出版日期2012-11-20