Ab initio calculations on pi-stacked thiophene dimer, trimer, and tetramer : structure, interaction energy, cooperative effects, and intermolecular electronic parameters

Pi-stacked complexes formed by two, three, and four thiophene rings have been investigated using abinitio quantum mechanical calculations. The relative orientation between the rings was investigated for each complex by exploring the corresponding potential energy surface at the MP2/6-31+G(d,p) level...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Journal of computational chemistry. - 1984. - 29(2008), 1 vom: 15. Jan., Seite 69-78
1. Verfasser: Rodríguez-Ropero, Francisco (VerfasserIn)
Weitere Verfasser: Casanovas, Jordi, Alemán, Carlos
Format: Aufsatz
Sprache:English
Veröffentlicht: 2008
Zugriff auf das übergeordnete Werk:Journal of computational chemistry
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Polymers Thiophenes
Beschreibung
Zusammenfassung:Pi-stacked complexes formed by two, three, and four thiophene rings have been investigated using abinitio quantum mechanical calculations. The relative orientation between the rings was investigated for each complex by exploring the corresponding potential energy surface at the MP2/6-31+G(d,p) level, the inter-ring distance, and the degree of tilting being examined in each case. Interaction energies were calculated at the MP2, MP3, MP4, and CCSD, levels of theory. Negligible or even slightly positive n-body effects have been predicted for the stacked thiophene arrangements studied in this work. This is consequence of the cancellation of favorable induction contribution by the destabilizing dispersion component. On the other hand analysis of the optimized geometries obtained for the trimer and tetramer revealed that the orientation of the rings presents a preferred degree of periodicity. Finally, we found that the lowest transition energy decreases when the size of the complex increases, this feature being attributed to desestabilization of the HOMO and stabilization of the LUMO that occur simultaneously
Beschreibung:Date Completed 12.03.2008
Date Revised 06.12.2007
published: Print
Citation Status MEDLINE
ISSN:1096-987X