Analysis of Hydrogen Bonds in Crystals

Abstract

Abstract:The determination of crystal structures provides important information on the geometry of species constituting crystals and on the symmetry relations between them. Additionally, the analysis of crystal structures is so conclusive that it allows us to understand the nature of various interactions. The hydrogen bond interaction plays a crucial role in crystal engineering and, in general, its important role in numerous chemical, physical and bio-chemical processes was the subject of various studies. That is why numerous important findings on the nature of hydrogen bonds concern crystal structures. This special issue presents studies on hydrogen bonds in crystals, and specific compounds and specific H-bonded patterns existing in crystals are analyzed. However, the characteristics of the H-bond interactions are not only analyzed theoretically; this interaction is compared with other ones that steer the arrangement of molecules in crystals, for example halogen, tetrel or pnicogen bonds. More general findings concerning the influence of the hydrogen bond on the physicochemical properties of matter are also presented.

Bifurcated Triel Bonds—Hydrides and Halides of 1,2-Bis(Dichloroboryl)Benzene and 1,8-Bis(Dichloroboryl)Naphthalene

“…The role of hydrogen bonds in the arrangement of molecules in crystal structures is very well known, and there are numerous early and recent studies describing this kind of interaction [1][2][3]. However also other interactions are crucial in crystal engineering, and the number of studies related to these interactions has significantly increased recently [4][5][6].…”

Lewis Acid Properties of Tetrel Tetrafluorides—The Coincidence of the σ-Hole Concept with the QTAIM Approach

“…The most often investigated hydrogen bond is crucial in numerous such processes [4][5][6][7] but there are also other significant interactions; for example, tetrel bond, which may be defined as an interaction between the Group 14 element acting as the Lewis acid centre and a region that is rich of the electron density by a lone electron pair, π-electron system, etc. [8][9][10][11][12].…”

The definitive challenge of forming uncommon pseudo‐π···H–F and C···H–F hydrogen bonds on cyclic and cubic nonpolar hydrocarbons

“…Commenting briefly, the eigenvalues of the Hessian matrix (r 2 ρ = λ 1 + λ 2 + λ 3 ) are useful to characterize the nonbonded contacts (λ 2 > 0) and bonding interactions (λ 2 < 0). [156] Notwithstanding the low values of charge density and long interaction distances, the values of sign (λ 2 )ρ smaller than zero in the 2D graphs certify the attractive character of the complexes, [153] although the discussions about the interaction strength theme cannot to be appraised yet. According to Grabowski, [18] the relationship between the intermolecular distance versus the electronic density computed on the BCP is useful to evaluate the interaction strength, and here our results yield a exponential decay model represented by Equation 17 and visualized in Figure 4.…”