Journal ArticleDOI
From weak to strong interactions: A comprehensive analysis of the topological and energetic properties of the electron density distribution involving X–H⋯F–Y systems
TLDR
In this paper, the topological and energetic properties of the electron density distribution ρ(r) of isolated pairwise H⋯F interaction have been theoretically calculated at several geometries and represented against the corresponding internuclear distances.Abstract:
The topological and energetic properties of the electron density distribution ρ(r) of the isolated pairwise H⋯F interaction have been theoretically calculated at several geometries (0.8<d<2.5 A) and represented against the corresponding internuclear distances. From long to short geometries, the results presented here lead to three characteristic regions, which correspond to three different interaction states. While the extreme regions are associated to pure closed-shell (CS) and shared-shell (SS) interactions, the middle one has been related to the redistribution of ρ(r) between those electronic states. The analysis carried out with this system has permitted to associate the transit region between pure CS and SS interactions to internuclear geometries involved in the building of the H–F bonding molecular orbital. A comparative analysis between the formation of this orbital and the behavior of some characteristic ρ(r) properties has indicated their intrinsic correspondence, leading to the definition of a bond degree parameter [BD=HCP/ρCP; HCP and ρCP being the total electron energy density and the electron density value at the H⋯F (3,−1) critical point]. Along with the isolated pairwise H⋯F interaction, 79 X–H⋯F–Y (neutral, positively and negatively charged) complexes have been also theoretically considered and analyzed in terms of relevant topological and energetic properties of ρ(r) found at their H⋯F critical points. In particular, the interaction energies of X–H⋯F–Y pure CS interactions have been estimated by using the bond degree parameter. On the other hand, the [F⋯H⋯F]− proton transfer geometry has been related to the local maximum of the electron kinetic energy density (GCP)max.read more
Citations
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Inter- and Intramolecular Bonding in 1,3,5-Triamino-2,4,6-trinitrobenzene: An Experimental and Theoretical Quantum Theory of Atoms in Molecules (QTAIM) Analysis
Zhijie Chua,Christopher G. Gianopoulos,Bartosz Zarychta,Bartosz Zarychta,Elizabeth A. Zhurova,Vladimir V. Zhurov,A. Alan Pinkerton +6 more
TL;DR: In this paper, the experimental electron density derived from X-ray diffraction data obtained at 20 K has been compared with those from solid state theoretical calculations, and the total electron density has been analyzed in terms of the Quantum Theory of Atoms in Molecules (QTAIM).
Journal ArticleDOI
Evolution of Bonding during the Insertion of Anionic Ibuprofen into Model Cell Membranes.
Natalia Rojas-Valencia,Sara Gómez,Sebastian Montillo,Marcela Manrique-Moreno,Chiara Cappelli,C. Z. Hadad,Albeiro Restrepo +6 more
TL;DR: Here, it is conclusively show that despite their purely classical origin, randomly chosen configurations from molecular dynamics simulations provide deep insight into the purely quantum nature of bonding interactions.
Journal ArticleDOI
Crystal Engineering and Charge Density Study of Pharmaceutical Nonlinear Optical Material: Melamine-Barbital Co-Crystal
TL;DR: In this paper, a topological analysis of charge density from multipolar refinement and ab initio calculations for both melamine-barbital co-crystal and isolated molecules is presented.
Journal ArticleDOI
cis Influence in Models of Cobalt Corrins by DFT and TD-DFT Studies
Isabelle Navizet,Christopher B. Perry,Penny Poomani Govender,Penny Poomani Govender,Helder M. Marques +4 more
TL;DR: Time-dependent density- functional theory and density-functional theory are applied to study the cis influence of the equatorial macrocycle in vitamin B(12) derivatives to explain the experimental observation that substitution of the axial ligand is more difficult and proceeds more slowly with the increase of the electron withdrawing power of the C(10) substituent.
Journal ArticleDOI
On the HOMA index of some acyclic and conducting systems
TL;DR: The geometrical aromaticity HOMA index can be useful for acyclic linear systems and approaches a horizontal asymptote as the periodic linear system increases in size as mentioned in this paper.
References
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Note on an Approximation Treatment for Many-Electron Systems
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Self‐consistent molecular orbital methods 25. Supplementary functions for Gaussian basis sets
TL;DR: In this paper, a modified basis set of supplementary diffuse s and p functions, multiple polarization functions (double and triple sets of d functions), and higher angular momentum polarization functions were defined for use with the 6.31G and 6.311G basis sets.