title: MP2 study of cation-(pi)n-pi interactions (n = 1-4).
abstract: Ab initio calculations at the MP2(full)/6-31++G**, RI-MP2(full)/6-31++G**, and RI-MP2(full)/6-311++G(2d,2p) levels of theory demonstrate important synergic effects between two noncovalent interactions that involve aromatic rings, that is, cation-pi and pi-pi interactions. The presence of a cation interacting with the pi cloud of an aromatic ring favors the face-to-face stacking interaction with additional aromatic rings. This effect is extended in the space up to five stacked aromatic rings.
authors.forename: Antonio
authors.initials: A
authors.lastname: Frontera
authors.forename: David
authors.initials: D
authors.lastname: Quiñonero
authors.forename: Carolina
authors.initials: C
authors.lastname: Garau
authors.forename: Antoni
authors.initials: A
authors.lastname: Costa
authors.forename: Pablo
authors.initials: P
authors.lastname: Ballester
authors.forename: Pere M
authors.initials: PM
authors.lastname: Deyà