Bo Jing

Bio: Bo Jing is an academic researcher from Yantai University. The author has contributed to research in topics: Chemical bond & Halogen bond. The author has an hindex of 13, co-authored 20 publications receiving 509 citations.

Competition between hydrogen bond and halogen bond in complexes of formaldehyde with hypohalous acids

Abstract: An ab initio study of the complexes formed by hypohalous acids (HOX, X = F, Cl and Br) with formaldehyde has been carried out at the MP2/aug-cc-pVTZ computational level. Two minima complexes are found, one with an H⋯O contact and the other one with an X⋯O contact. The former is more stable than the latter, and the strength difference between them decreases as the size of the X atom increases. The associated HO and XO bonds undergo a bond lengthening and red shift, whereas a blue shift was observed in the bond of the hypohalous acid not involved in the interaction. The interaction strength and properties in both complexes are analyzed with atoms in molecules (AIM) and natural bond orbital (NBO) theories. The energy decomposition analyses indicate that the contribution from the electrostatic interaction energy is larger in the hydrogen-bonded complexes than that in the halogen-bonded complexes.

Some measures for making halogen bonds stronger than hydrogen bonds in H2CS-HOX (X = F, Cl, and Br) complexes.

Abstract: The properties and applications of halogen bonds are dependent greatly on their strength. In this paper, we suggested some measures for enhancing the strength of the halogen bond relative to the hydrogen bond in the H2CS–HOX (X = F, Cl, and Br) system by means of quantum chemical calculations. It has been shown that with comparison to H2CO, the S electron donor in H2CS results in a smaller difference in strength for the Cl halogen bond and the corresponding hydrogen bond, and the Br halogen bond is even stronger than the hydrogen bond. The Li atom in LiHCS and methyl group in MeHCS cause an increase in the strength of halogen bonding and hydrogen bonding, but the former makes the halogen bond stronger and the latter makes the hydrogen bond stronger. In solvents, the halogen bond in the Br system is strong enough to compete with the hydrogen bond. The interaction nature and properties in these complexes have been analyzed with the natural bond orbital theory.

A new unconventional halogen bond C ? X···H ? M between HCCX (X = Cl and Br) and HMH (M = Be and Mg): An ab initio study

Abstract: In this article, a new type of halogen-bonded complex YCCX···HMY (X = Cl, Br; M = Be, Mg; Y = H, F, CH3) has been predicted and characterized at the MP2/aug-cc-pVTZ level. We named it as halogen-hydride halogen bonding. In each YCCX···HMY complex, a halogen bond is formed between the positively charged X atom and the negatively charged H atom. This new kind of halogen bond has similar characteristics to the conventional halogen bond, such as the elongation of the CX bond and the red shift of the CX stretch frequency upon complexation. The interaction strength of this type of halogen bond is in a range of 3.34–10.52 kJ/mol, which is smaller than that of dihydrogen bond and conventional halogen bond. The nature of the electrostatic interaction in this type of halogen bond has also been unveiled by means of the natural bond orbital, atoms in molecules, and energy decomposition analyses. © 2009 Wiley Periodicals, Inc. J Comput Chem 2010

Prominent Effect of Alkali Metals in Halogen-Bonded Complex of MCCBr−NCM′ (M and M′ = H, Li, Na, F, NH2, and CH3)

Abstract: Quantum chemical calculations have been performed for the MCCBr−NCM′ (M and M′ = H, Li, Na, F, NH2, and CH3) halogen-bonded complexes at the MP2/aug-cc-pVTZ level. The binding energy is in a range of 1.34−23.42 kJ/mol. The results show that the alkali metal has a prominent effect on the strength of halogen bond, and this effect is different for the alkali metal in the halogen and electron donors. The alkali atom in the halogen donor makes it weaken greatly, whereas that in the electron donor causes it to enhance greatly. Natural bond orbital analysis shows that the alkali atom is electron-withdrawing in the halogen donor and electron-donating in the electron donor. In formation of the halogen bond, the former is a negative contribution, whereas the latter is a positive one. A similar charge transfer is also found for the H atom in the halogen and electron donors. These complexes have also been analyzed with the atoms in molecules theory.

Novel halogen-bonded complexes H3NBH3...XY (XY = ClF, ClCl, BrF, BrCl, and BrBr): partially covalent character.

Abstract: Quantum chemical calculations have been performed to study the interaction of H3NBH3 with dihalogen molecules XY (XY = ClF, ClCl, BrF, BrCl, and BrBr) at the MP2/aug-cc-pVTZ level. It is shown that a halogen−hydride halogen bond is formed between the two molecules, in which the σ electron of the B−H bond in H3NBH3 acts as the electron donor. The strength of the halogen bond ranges from 14.82 kJ/mol in H3NBH3−ClCl complex to 40.13 kJ/mol in H3NBH3−BrF complex at the CCSD(T)/aug-cc-pVTZ level, which is comparable to medium strong hydrogen bonds. The B−H and X−Y bonds are elongated with a concomitance of a red shift. The analyses of natural bond orbital and atoms in molecules have been carried out to understand the nature of properties of this novel interaction. The results show that this interaction has partially covalent character.

Halogen bonding and other σ-hole interactions: a perspective

Abstract: A σ-hole bond is a noncovalent interaction between a covalently-bonded atom of Groups IV–VII and a negative site, e.g. a lone pair of a Lewis base or an anion. It involves a region of positive electrostatic potential, labeled a σ-hole, on the extension of one of the covalent bonds to the atom. The σ-hole is due to the anisotropy of the atom's charge distribution. Halogen bonding is a subset of σ-hole interactions. Their features and properties can be fully explained in terms of electrostatics and polarization plus dispersion. The strengths of the interactions generally correlate well with the magnitudes of the positive and negative electrostatic potentials of the σ-hole and the negative site. In certain instances, however, polarizabilities must be taken into account explicitly, as the polarization of the negative site reaches a level that can be viewed as a degree of dative sharing (coordinate covalence). In the gas phase, σ-hole interactions with neutral bases are often thermodynamically unfavorable due to the relatively large entropy loss upon complex formation.

Halogen Bonding: An Interim Discussion

Abstract: Halogen bonding is a noncovalent interaction that is receiving rapidly increasing attention because of its significance in biological systems and its importance in the design of new materials in a variety of areas, for example, electronics, nonlinear optical activity, and pharmaceuticals. The interactions can be understood in terms of electrostatics/polarization and dispersion; they involve a region of positive electrostatic potential on a covalently bonded halogen and a negative site, such as the lone pair of a Lewis base. The positive potential, labeled a σ hole, is on the extension of the covalent bond to the halogen, which accounts for the characteristic near-linearity of halogen bonding. In many instances, the lateral sides of the halogen have negative electrostatic potentials, allowing it to also interact favorably with positive sites. In this discussion, after looking at some of the experimental observations of halogen bonding, we address the origins of σ holes, the factors that govern the magnitudes of their electrostatic potentials, and the properties of the resulting complexes with negative sites. The relationship of halogen and hydrogen bonding is examined. We also point out that σ-hole interactions are not limited to halogens, but can also involve covalently bonded atoms of Groups IV-VI. Examples of applications in biological/medicinal chemistry and in crystal engineering are mentioned, taking note that halogen bonding can be "tuned" to fit various requirements, that is, strength of interaction, steric factors, and so forth.