A theoretical study of the azide (N-3) doublet states. A new route to tetraazatetrahedrane (N-4): N+N-3 -> N-4
2002 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 116, no 22, 9740-9748 p.Article in journal (Refereed) Published
The potential energy surfaces for the low-lying doublet states of the azide radical (N-3) have been computed at the complete active space self-consistent field (CASSCF) level with the CAS(15,12) active space. The cc-pVTZ and aug-cc-pVTZ basis sets have been employed throughout the present work. Energies, geometries and harmonic frequencies were determined for the N-3 linear ground electronic state ((2)Pi(g)), a stable C-2v ring structure (B-2(1)), and a C-s transition state ((2)A(')) connecting the ring and linear structures. Other N-3 (C-2v) stationary points ((2)A(2), B-2(1), and (2)A(1)) have been characterized, as well. The vertical excitation energies for the doublet excited states of the N-3 linear ((2)Pi(g)) and stable ring (B-2(1)) isomers were calculated using CASSCF and multireference configuration interaction [MRCI-SD(Q)] methods. A new route to tetraazatetrahedrane [N-4(T-d)] has been proposed on the N-4 singlet potential energy surface within C-s symmetry. MRCI-SD(Q) calculations predict that N-4 (T-d) can be formed from atomic nitrogen in the D-2 state and N-3 (C-2v, B-2(1)) in a barrierless exothermic reaction. The energy difference (D-0) is 135.4 kcal/mol at the MRCI-SD(Q) level.
Place, publisher, year, edition, pages
2002. Vol. 116, no 22, 9740-9748 p.
configuration-interaction calculations, density-functional thermochemistry, correlated molecular calculations, potential-energy surface, gaussian-basis sets, shell hartree-fock, n(d-2)+h-2 reaction, tetrahedral n-4, nitrogen-atoms, solid nitrogen
IdentifiersURN: urn:nbn:se:kth:diva-21559DOI: 10.1063/1.1476310ISI: 000175744600023OAI: oai:DiVA.org:kth-21559DiVA: diva2:340257
QC 201005252010-08-102010-08-10Bibliographically approved