scispace - formally typeset
Search or ask a question
Author

Xiulin An

Bio: Xiulin An is an academic researcher from Yantai University. The author has contributed to research in topics: Hydrogen bond & Methyl group. The author has an hindex of 12, co-authored 17 publications receiving 460 citations.

Papers
More filters
Journal ArticleDOI
TL;DR: The cooperativity contribution in the single-electron hydrogen bond is larger than that in the hydrogen bond of HCN-HCN and HNC-HNC complexes and NMR chemical shifts, charge transfers, and topological parameters also support such conclusions.
Abstract: Hydrogen-bonded clusters, H3C–HCN, HCN–HCN, H3C–HCN–HCN, H3C–HNC, HNC–HNC, and H3C–HNC–HNC, have been studied by using ab initio calculations. The optimized structures, harmonic vibrational frequencies, and interaction energies are calculated at the MP2 level with aug-cc-pVTZ basis set. The cooperative effects in the properties of these complexes are investigated quantitatively. A cooperativity contribution of around 10% relative to the total interaction energy was found in the H3C–HCN–HCN complex. In the case of H3C–HNC–HNC complex, the cooperativity contribution is about 15%. The cooperativity contribution in the single-electron hydrogen bond is larger than that in the hydrogen bond of HCN–HCN and HNC–HNC complexes. NMR chemical shifts, charge transfers, and topological parameters also support such conclusions.

56 citations

Journal ArticleDOI
Qingzhong Li1, Ting Hu1, Xiulin An1, Baoan Gong1, Jianbo Cheng1 
TL;DR: NBO analyses indicate that orbital interaction, charge transfer, and bond polarization are mainly responsible for the cooperativity between the two types of hydrogen bonds.
Abstract: The cooperativity between the dihydrogen bond and the N⋅⋅⋅HC hydrogen bond in LiH–(HCN)n (n=2 and 3) complexes is investigated at the MP2 level of theory. The bond lengths, dipole moments, and energies are analyzed. It is demonstrated that synergetic effects are present in the complexes. The cooperativity contribution of the dihydrogen bond is smaller than that of the N⋅⋅⋅HC hydrogen bond. The three-body energy in systems involving different types of hydrogen bonds is larger than that in the same hydrogen-bonded systems. NBO analyses indicate that orbital interaction, charge transfer, and bond polarization are mainly responsible for the cooperativity between the two types of hydrogen bonds.

49 citations

Journal ArticleDOI
Xiulin An1, Haiping Liu1, Qingzhong Li1, Baoan Gong1, Jianbo Cheng1 
TL;DR: The effect of substitution, hybridization, and solvent on the properties of the C...HO single-electron hydrogen bond has been investigated with quantum chemical calculations and methyl radical, ethyl radical, and vinyl radical are used as the proton acceptors.
Abstract: The effect of substitution, hybridization, and solvent on the properties of the C···HO single-electron hydrogen bond has been investigated with quantum chemical calculations. Methyl radical, ethyl radical, and vinyl radical are used as the proton acceptors and are paired with water, methanol, HOCl, and vinyl alcohol. Halogenation (Cl) of the proton donor strengthens this type of hydrogen bond. The methyl group in the proton donor and proton acceptor plays a different role in the formation of the C···HO single-electron hydrogen bond. The former is electron-withdrawing, and the latter is electron-donating, both making a constructive contribution to the enhancement of the interaction. The contribution of the methyl group in the proton acceptor is larger than that in the proton donor. The increase of acidity of the proton is helpful to form a single-electron hydrogen bond. As the proton acceptor varies from the methyl radical to the vinyl radical, the interaction strength also increases. The solvent has an en...

49 citations

Journal ArticleDOI
TL;DR: Calculations for chalcogen- and halogen-bonded complexes of F2CSe with a series of nitrogen bases and dihalogen molecules confirm the abundance of Se···N interaction in crystal materials.
Abstract: Quantum-chemical calculations have been performed for the chalcogen- and halogen-bonded complexes of F2CSe with a series of nitrogen bases (N2, NCH, NH3, NHCH2, NCLi, and NMe3) and dihalogen molecules (BrCl, ClF, and BrF), respectively. Both types of interactions are mainly driven by the electrostatic and orbital interactions. The chalcogen bond becomes stronger in the order of NCH (sp) < NH3 (sp3) < NHCH2 (sp2), showing some inconsistence with the electronegativity of the hybridized N atom. The Li and methyl groups have an enhancing effect on the strength of chalcogen bond; however, the former is jointly achieved through the electrostatic and orbital interactions, whereas the orbital interaction has dominant contribution to the latter enhancement. The halogen bond with F2CX (X = O, S, Se) as the electron donor is stronger for the heavier chalcogen atom, exhibiting a reverse dependence on the chalcogen atom with that in hydrogen bonds. The halogen bond is further strengthened by the presence of chalcogen ...

46 citations

Journal ArticleDOI
TL;DR: The cooperativity between red-shifted hydrogen bond and blue-shifting hydrogen bond in dimethyl sulfoxide aqueous solutions was studied by methods of quantum chemical calculations and infrared spectroscopy.

46 citations


Cited by
More filters
Journal ArticleDOI
01 Jan 2011
TL;DR: A review of the current state of knowledge of the fundamental sooting processes, including the chemistry of soot precursors, particle nucleation and mass/size growth, can be found in this article.
Abstract: Over the last two decades, our understanding of soot formation has evolved from an empirical, phenomenological description to an age of quantitative modeling for at least small fuel compounds. In this paper, we review the current state of knowledge of the fundamental sooting processes, including the chemistry of soot precursors, particle nucleation and mass/size growth. The discussion shows that though much progress has been made, critical gaps remain in many areas of our knowledge. We propose the roles of certain aromatic radicals resulting from localized π electron structures in particle nucleation and subsequent mass growth. The existence of these free radicals provides a rational explanation for the strong binding forces needed for forming initial clusters of polycyclic aromatic hydrocarbons. They may also explain a range of currently unexplained sooting phenomena, including the large amount of aliphatics observed in nascent soot formed in laminar premixed flames and the mass growth of soot in the absence of gas-phase H atoms. While the above suggestions are inspired, to an extent, by recent theoretical findings from the materials research community, this paper also demonstrates that the knowledge garnered through our longstanding interest in soot formation may well be carried over to flame synthesis of functional nanomaterials for clean and renewable energy applications. In particular, work on flame-synthesized thin films of nanocrystalline titania illustrates how our combustion knowledge might be useful for developing advanced yet inexpensive thin-film solar cells and chemical sensors for detecting gaseous air pollutants.

953 citations

Journal ArticleDOI
TL;DR: This discussion addresses 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, and points out that σ-hole interactions are not limited to halogens, but can also involve covalently bonded atoms of Groups IV-VI.
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.

596 citations