Core-electron contributions to the magnetic response of molecules with heavy elements and their significance in aromaticity assessments

Abstract

This study delves into the magnetic response of core electrons and their influence on the global magnetic response of systems planar and three-dimensional containing heavy elements, employing the removing valence electron (RVE) approximation. We also explore electronic aromaticity indices to understand the potential role of core electrons on electron delocalization in absence of an external perturbation. The study reveals that core electrons significantly contribute to the overall magnetic response, especially to the magnetic shielding, affecting the interpretation of aromaticity. In contrast, the calculation of the electronic aromaticity indices suggests a negligible participation of the core electrons to the electron delocalization. Despite its widespread use, the study emphasizes caution in labeling systems as strongly aromatic based solely on shielding function computations. It is noteworthy to emphasize the limitations associated with each aromaticity criterion, particularly in the context of magnetic shielding function calculations, the core-electron effect contamination is undeniable. Hence, the integration of various criteria becomes imperative for attaining a comprehensive understanding of magnetic responses within complex systems.

Multiconfigurational actinide nitrides assisted by double Möbius aromaticity

“…There are diatropic ring-currents inside and outside of the ring, which become much clearer at 5.0 Bohr above the molecular plane. It is also obvious that the paramagnetic currents induced by core electrons on metal centers have a significant effect on the inner and outer ring-currents in U 2 N 2 , in agreement with the findings by Orozco-Ic et al 94 In order to eliminate the effect of core electrons, we calculated the induced current by setting the end point of the crossing plane at the midpoint of the An–N bond, 98 which can better reflect the strength of the inner ring-current. As listed in Table 2 , the results indicate that An 2 N 2 is magnetically aromatic, which is comparable to and even stronger than the aromaticity in benzene with a J int value of around 12 n A/T.…”

“…In contrast, the global diamagnetic induced ring-current is believed to be a more reliable criterion for aromaticity in heavy metal clusters, [90][91][92][93] and has been well-validated in a comprehensive theoretical work by Orozco-Ic et al very recently. 94 Therefore, we performed rigorous ring-current analyses. Fig.…”