Estudi de la reactivitat d’una caixa M@C36 reaccions Diels-Alder

Abstract

Fullerenes are the third most stable form of carbon, below diamond and graphite, and they exhibit unique properties that have made them objects of interest in recent years. One of the interesting properties of fullerenes is their capacity to encapsulate atoms, ions, metallic clusters, and small molecules. Endohedral metallofullerenes (MFEs) are the product of encapsulating metals within a specific fullerene. These materials possess unique properties that make them promising in various fields such as materials science and biology. Currently, the majority of successfully synthesized and separated MFEs correspond to those in which the encapsulated metal belongs to groups 2 and 3, and when encapsulation is carried out using fullerenes with a large volume (C60, C70, C78...), especially in the case of C82. Different studies demonstrate that in many cases, the most stable position of the metal is not found at the center of the cage but rather displaced toward its walls, thus demonstrating the metal-cage interactions that occur in this process. In this study, the energy viability of encapsulating different metals (Sc3+ and Zn2+) within a C36 cage is verified, which itself exhibits higher reactivity than in the case of the larger cages mentioned earlier. Furthermore, the most stable position of the metals inside and the reactivity of M@C36 in a Diels-Alder cycloaddition reaction between s-cis-1,3-butadiene and all the non-equivalent bonds of the corresponding C36 are studied, taking into account the different spin states associated with them. The study is conducted using DFT calculations with the S12g4 /tz2p density functional, which was specifically developed for systems with high electron density and has yielded satisfactory results in most of the proposed calculations