Ab initio study of the π–π interactions between CO2 and benzene, pyridine, and pyrrole. Issue 20 (24th May 2013)

• Record Type: Journal Article
• Authors: Chen, Long; Cao, Fenglei; Sun, Huai
• Is Part Of: International journal of quantum chemistry. Volume 113:Issue 20(2013:Oct. 15)
• Page Start: 2261
• Page End: 2266
• Publication Date: 2013-05-24
• Subjects: Quantum chemistry -- Periodicals; 541.28
• DOI: 10.1002/qua.24444
• Languages: English
• ISSNs: 0020-7608

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The π–π interactions between CO<sub>2</sub> and three aromatic molecules, namely benzene (C<sub>6</sub>H<sub>6</sub>), pyridine (C<sub>5</sub>H<sub>5</sub>N), and pyrrole (C<sub>4</sub>H<sub>5</sub>N), which represent common functional groups in metal‐organic/zeoliticimidazolate framework materials, were characterized using high‐level <italic>ab initio</italic> methods. The coupled‐cluster with single and double excitations and perturbative treatment of triple excitations (CCSD(T)) method with a complete basis set (CBS) was used to calibrate Hartree–Fock, density functional theory, and second‐order M⊘ller–Plesset (MP2) with resolution of the identity approximation calculations. Results at the MP2/def2‐<italic>Q</italic>ZVPP level showed the smallest deviations (only about 1 kJ/mol) compared with those at the CCSD(T)/CBS level of theory. The strength of π–π binding energies (BEs) followed the order C<sub>4</sub>H<sub>5</sub>N > C<sub>6</sub>H<sub>6</sub> ∼ C<sub>5</sub>H<sub>5</sub>N and was roughly correlated with the aromaticity and the charge transfer between CO<sub>2</sub> and aromatic molecule in clusters. Compared with hydrogen‐bond or electron donor–acceptor interactions observed during BE calculations at the MP2/def2‐<italic>Q</italic>ZVPP level of theory, π–π interactions significantly contribute to the total interactions between CO<sub>2</sub> and aromatic molecules. © 2013 Wiley Periodicals, Inc.</p> </abstract>