The Nature of Transannular Interactions in E4N4 and E82+ (E = S, Se)
Moilanen, J., Karttunen, A., Tuononen, H., & Chivers, T. (2012). The Nature of Transannular Interactions in E4N4 and E82+ (E = S, Se). Journal of Chemical Theory and Computation, 8 (11), 4249-4258. doi:10.1021/ct300627p
Published inJournal of Chemical Theory and Computation
DisciplineEpäorgaaninen ja analyyttinen kemia
© 2012 American Chemical Society. This is a final draft version of an article whose final and definitive form has been published by ACS. Published in this repository with the kind permission of the publisher.
The electronic structures of tetrachalcogen tetranitrides, E4N4, and octachalcogen dications, E82+, and the nature of their intramolecular E···E interactions (E = S, Se) was studied with high-level theoretical methods. The results reveal that the singlet ground states of both systems have a surprisingly large correlation contribution which functions to weaken and therefore lengthen the cross-ring E–E bond. The observed correlation effects are primarily static in E4N4, whereas in E82+ the dynamic part largely governs the total correlation contribution. The presented description of bonding is the first that gives an all-inclusive picture of the origin of cross-ring interactions in E4N4 and E82+; not only does it succeed in reproducing all experimental structures but it also offers a solid explanation for the sporadic performance of different computational methods that has been reported in previous studies. Furthermore, the theoretical data demonstrate that E···E bonds in E4N4 and E82+ are unique and fundamentally different from, for example, dispersion that plays a major role in weak intermolecular chalcogen···chalcogen contacts. ...