Probing the Interaction of NO with C₆₀: Comparison between Endohedral and Exohedral Complexes

Abstract

Recent advances in synthetic methodologies have opened new strategies for synthesizing stable metal-free electron spin systems based on fullerenes. Introducing nitric oxide (NO) inside a fullerene cage is one of the methods to attain this goal. In the present study, dispersion corrected density functional theory (B3LYP-D3) has been used to evaluate the structure, stability, and electronic properties of NO encapsulated fullerene NO@C60 and compared those with its exohedral fullerene NO.C60 analog. The calculated stabilization energy for NO@C60 is appreciably higher than NO.C60, and this difference is comprehended via the Quantum theory of atoms in molecules (QTAIM) and noncovalent interaction (NCI) topological analyses. The delocalization of electron density of NO and the C60 cage in NO@C60 is discussed using electrostatic potential analysis. In addition, an attempt has been made to understand the different locations and orientations involving the interaction of two NO radicals and the fullerene C60. It is shown that the encapsulation of the NO dimer inside the C60 cage is an energetically unfavorable process. On the other hand, stable structures are obtained upon the physisorption of other NO on the surface of NO@C60 and NO.C60. The present work provides an in-depth understanding of the interaction of NO and C60 fullerene, its preferable position, and its orientation in both endohedral and exohedral complexes.

Theoretical Insights into the Structural and Optical Properties of D−π–A-based Cyanostilbene Systems of α and β Variants

“…NCI and QTAIM analyses serve as a valuable tool to identify, visualize, and quantify various inter and intramolecular chemical interactions present in molecular systems. − We further performed NCI and QTAIM analyses to unravel various NCIs present within the designed molecules. As shown in Figure , the RDG isosurfaces resulting from the NCI analysis of representative isomeric pairs P 4 and P 7 are shown.…”

Interplay of Hydrogen, Pnicogen, and Chalcogen Bonding in X(H2O)n=1–5 (X = NO, NO+, and NO–) Complexes: Energetics Insights via a Molecular Tailoring Approach

“…The quantum theory of atoms in molecules (QTAIM) analysis, founded on the topological features of electron density, is a routinely used tool for quantitatively assessing molecular interactions. ,− The presence of a bond critical point (bcp) shows the bonding interaction between two atoms, and its strength can be assessed with the molecular electron density value ( ρ ( r )) at the bcp. In the next step, we compared the trends in the HB/PB energies and ρ ( r ) values of the same in the NO­(H 2 O) n =1–5 complexes.…”

Bond Strength and Interaction Energies in Togni Reagents: Insights from Molecular Electrostatic Potential-Based Parameters

“…It is well established that MESP-based topology parameters can be used to investigate the electronic effects of different substituents in various systems. , Particularly, MESP topology analysis facilitates the direct visualization of electronic perturbations resulting from substitutions in the aromatic ring. , In such an analysis, electron-dense regions, such as anionic, lone pairs, and π-electron clouds of a molecule, are identified on the basis of the (3, +3) critical point values, which are also referred to as the locus of a minimum of the MESP value (designated as V min ). − Sajith and Suresh demonstrated the significance of the V min analysis in quantifying the cis and trans influences in various acyclic and heterocyclic hypervalent iodine compounds. , This quantification aids in understanding the stability and reaction mechanisms of hypervalent iodine-mediated reactions.…”