Through-Bond-Driven Through-Space Interactions in a Fullerene C₆₀ Noncovalent Dyad: An Unusual Strong Binding between Spherical and Planar π Electron Clouds and Culmination of Dyadic Fractals

Abstract

Hydrogen-bond-induced π-depletion as a criterion for π-stacking, a configurationally unique noncovalent strategy enabled an unconventional strong binding between the spherical N-fulleropyrrolidine (NFP) and the planar distributions of π electron clouds of three substituted pybates to form noncovalent fulleropyrrolidino-4-(pyrenyl) butanoate dyads of large computed interaction energies, varying between 37.49 and 44.93 kcal/mol. The geometrical distortion/bending of the alkyl tail of pybate in the noncovalent dyad was experimentally corroborated via UV−vis absorption spectroscopy, which translated into spectral broadening along with pronounced shifts in the n−π* transitions of the oxy-substituted pyrene in different solvents, ensuring through-bond interactions. Facile electron transfer through H-bond influenced the dynamic dispersive forces to be active, revealing the supremacy of through-bond over through-space interactions. The analyses of intermolecular forces using an absolutely localized molecular orbital-based energy decomposition analysis (ALMO-EDA) scheme revealed intricate insights into the intermolecular interactions and characteristic charge transfer; the dominance of forward electron transfer (pybate to NFP) over the reverse in offering stabilization was noted. Charge transfer was investigated further from natural bond orbital (NBO) and absolutely localized molecular orbital-based charge-transfer analysis (ALMO-CTA) methods, establishing the supremacy of donor-to-acceptor electron transfer over the reverse (acceptor-to-donor) one. The characteristic self-assembly of the noncovalent dyad in suitable solvents led to the formation of fractal networks via reaction-limited cluster aggregation with a fractal dimension of 2.37. Adoption of constrained molecular dynamics simulations indicated probable wrapping of pybates around NFP, leading to fractal-like assembly.

Heteroatoms (Si, B, N, and P) doped 2D monolayer MoS2for NH3gas detection

“… 42 A thorough literature review showed that the higher the stabilization energy the stronger the interaction between the donor orbital and acceptor orbital and the stronger the strength of adsorption of the sensing materials. 43 The second-order perturbation energy of the studied doped MoS 2 monolayer and its interaction with NH 3 gas was estimated using eqn (6) 44 where q i is the donor orbital occupancy, ε i , and ε j represent the diagonal elements and F ( i , j ) stands for the off-diagonal elements of the Fock matrix.…”

Reciprocity of CO⋯π interactions with the dominant anion–π on fullerene (C60)– amine-based organocatalysts: a mechanistic elucidation for additionvs.decarboxylation reaction

“…SPE calculations were carried out using the 6-311+G(d,p) basis set at B3LYP, M06-2X, and ωB97X-D functionals. 35 The polarizable continuum model 36–38 (PCM) implemented in the Gaussian 16 program package was used to incorporate the solvation (THF) effect at B3LYP, M06-2X, and ωB97X-D theory levels, the last two being hybrid long-range separated functionals, which take care of empirically-corrected dispersion interactions for studying structures with non-covalent interactions of the catalyst C 60 -substrate type. In separate sets of calculations, relative free energies were obtained using the B3LYP-D3 level of theory to incorporate dispersion correction for all the intermediates in Scheme 1A and B, the details of which are provided in Tables S1 and S2 (see ESI†).…”