Relevant bibliographies by topics / Hydrogen bond; Ions; Charge-transfer

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  1. Journal articles
  2. Dissertations / Theses
  3. Book chapters
  4. Conference papers

Academic literature on the topic 'Hydrogen bond; Ions; Charge-transfer'

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Published: 4 June 2021
Last updated: 4 February 2022

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Journal articles on the topic "Hydrogen bond; Ions; Charge-transfer"

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Ruttink, Paul J. A., Peter C. Burgers, and Johan K. Terlouw. "Proton and electron transfers in O•H•O and C•H•O hydrogen-bridged ions: their role in the dissociation chemistry of ionized acetol, CH3C(=O)CH2OH•+." Canadian Journal of Chemistry 74, no. 6 (1996): 1078–87. http://dx.doi.org/10.1139/v96-121.

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Low-energy acetol ions CH3C(=O)CH2OH•+, 1, dissociate to CH3C(H)OH+ and HC=O• by a double hydrogen transfer (DHT), a common reaction among oxygen-containing radical cations. Recent experimental work has shown that the isotopologue CH3C(=O)CH2OD•+ specifically loses HC=O• to produce CH3C(D)OH+. This finding refutes an earlier postulated attractive mechanism based on the behaviour of 1 in ion-molecule reactions. Using ab initio MO calculations (at the CEPA//RHF/DZP level of theory complemented with valence bond (VB) methods), a low-energy pathway was traced that may explain all of the available
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Tiritiris, Ioannis, and Willi Kantlehner. "Crystal structure ofN,N,N′,N′,N′′,N′′-hexamethylguanidinium cyanate 1.5-hydrate." Acta Crystallographica Section E Crystallographic Communications 71, no. 12 (2015): o1076—o1077. http://dx.doi.org/10.1107/s2056989015024317.

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The title hydrated salt, C7H18N3+·OCN−.1.5H2O, was synthesized starting fromN,N,N′,N′,N′′,N′′-hexamethylguanidinium chloride by a twofold anion-exchange reaction. The asymmetric unit contains two cations, two cyanate anions and three water molecules. One cation shows orientational disorder and two sets of N-atom positions were found related by a 60° rotation, with an occupancy ratio of 0.852 (6):0.148 (6). The C—N bond lengths in both guanidinium ions range from 1.329 (2) to 1.358 (10) Å, indicating double-bond character, pointing towards charge delocalization within the NCN planes. Strong O—H
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Girisha, Marisiddaiah, Hemmige S. Yathirajan, Jerry P. Jasinski, and Christopher Glidewell. "Different acid–base behaviour of a pyrazole and an isoxazole with organic acids: crystal and molecular structures of the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate and of the cocrystal 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide–3,5-dinitrobenzoic acid (1/1)." Acta Crystallographica Section C Structural Chemistry 72, no. 8 (2016): 612–18. http://dx.doi.org/10.1107/s2053229616010494.

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Pyrazole and isoxazole rings differ only in the notional replacement of a potential hydrogen-bond-donor NH unit in pyrazole by a potential hydrogen-bond-acceptor O atom in isoxazole. It is thus of interest to compare the hydrogen-bonding characteristics of these rings. (4-Fluorophenyl)pyrazole undergoes protonation in the presence of 2,4,6-trinitrophenol to yield the salt 3-(4-fluorophenyl)-1H-pyrazolium 2,4,6-trinitrophenolate, C9H8FN2+·C6H2N3O7−, (I), whereas there is no proton transfer between 4-amino-N-(3,4-dimethyl-1,2-oxazol-5-yl)benzenesulfonamide and 3,5-dinitrobenzoic acid, whose reac
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Amraoui, Nour Elyakine, and Dalila Hammoutène. "DFT study and topological analysis of the bonding in DNA Hoogsteen-type base pairs." Journal of Theoretical and Computational Chemistry 14, no. 07 (2015): 1550047. http://dx.doi.org/10.1142/s0219633615500479.

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The purpose of our work is to characterize and present a theoretical comparative study of a variety of compounds based on DNA base pairs linked with some transition metal ions in gas phase: C–M–G (Cytosine–metal–Guanine) where [Formula: see text](I), Zn(II), Cd(II) and A–M–T (Adenine–metal–Thyminate) where [Formula: see text](II), Ru(I), Ni(I), Y(II), Zn(I), Cd(I), Cu(II). Geometry optimization and frequency calculations were carried out at DFT/ZORA/BLYP-D/TZ2P level. M–N and M–O bonds were investigated with the quantum chemical topology (QCT): Quantum theory of atoms in molecules (QTAIM) and
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Chen, Yixing, Halil I. Okur, Nikolaos Gomopoulos, et al. "Electrolytes induce long-range orientational order and free energy changes in the H-bond network of bulk water." Science Advances 2, no. 4 (2016): e1501891. http://dx.doi.org/10.1126/sciadv.1501891.

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Electrolytes interact with water in many ways: changing dipole orientation, inducing charge transfer, and distorting the hydrogen-bond network in the bulk and at interfaces. Numerous experiments and computations have detected short-range perturbations that extend up to three hydration shells around individual ions. We report a multiscale investigation of the bulk and surface of aqueous electrolyte solutions that extends from the atomic scale (using atomistic modeling) to nanoscopic length scales (using bulk and interfacial femtosecond second harmonic measurements) to the macroscopic scale (usi
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Knorr, Anne, Koichi Fumino, Anne-Marie Bonsa, and Ralf Ludwig. "Spectroscopic evidence of ‘jumping and pecking’ of cholinium and H-bond enhanced cation–cation interaction in ionic liquids." Physical Chemistry Chemical Physics 17, no. 46 (2015): 30978–82. http://dx.doi.org/10.1039/c5cp03412d.

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Tsuneda, Takao, and Tetsuya Taketsugu. "Theoretical investigations on hydrogen peroxide decomposition in aquo." Physical Chemistry Chemical Physics 20, no. 38 (2018): 24992–99. http://dx.doi.org/10.1039/c8cp04299c.

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Hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) decomposition mechanisms in the absence and presence of iron ions in aqueous solution, which contain no OH radical formation, are theoretically determined. H<sub>2</sub>O<sub>2</sub> decomposition in the presence of iron ions is driven by electron transfer to the iron ion and proceeds by hydrogen transfers in the hydrogen bond network around H<sub>2</sub>O<sub>2</sub>.
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Bibi, Naheed, Renan Barrach Guerra, Luis Enrique Santa Cruz Huamaní та André Luiz Barboza Formiga. "Crystal structure, electrochemical and spectroscopic investigation of mer-tris[2-(1H-imidazol-2-yl-κN 3)pyrimidine-κN 1]ruthenium(II) bis(hexafluoridophosphate) trihydrate". Acta Crystallographica Section E Crystallographic Communications 74, № 7 (2018): 874–77. http://dx.doi.org/10.1107/s2056989018007995.

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The crystal structure of the title compound, [Ru(C7H6N4)3](PF6)2·3H2O, a novel RuII complex with the bidentate ligand 2-(1H-imidazol-2-yl)pyrimidine, comprises a complex cation in the meridional form exclusively, with a distorted octahedral geometry about the ruthenium(II) cation. The Ru—N bonds involving imidazole N atoms are comparatively shorter than the Ru—N bonds from pyrimidine because of the stronger basicity of the imidazole moiety. The three-dimensional hydrogen-bonded network involves all species in the lattice with water molecules interacting with both counter-ions and NH hydrogen a
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Liu, Ji, Wei Zhao, Xinrui Fan, Mingxin Xu, Shu Zheng, and Qiang Lu. "Effect of alkali metal ions on the formation mechanism of HCN during pyridine pyrolysis." International Journal of Coal Science & Technology 8, no. 3 (2021): 349–59. http://dx.doi.org/10.1007/s40789-021-00427-3.

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AbstractThe catalytic effects of alkali metal ions (Na+ and K+) on NOx precursor formation during coal pyrolysis were investigated using the N-containing compound pyridine as a model compound. Density functional theory calculations at the B3LYP/6-31G (d, p) level of theory were conducted to elucidate the mechanism of pyridine pyrolysis and the pathways for HCN formation. The calculation results indicate that Na+ and K+ have distinct influences on different pyrolysis reactions; these alkali metal ions facilitate the initial hydrogen transfer from C1 to N and C2, whereas they hinder the other hy
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Závada, Jiří, Václav Pechanec, and Oldřich Kocián. "Anion effect on alkali ion-crown complex formation in a moderately concentrated solutions: A sensitive probe of hidden interionic interactions operating in dissociating protic solvents." Collection of Czechoslovak Chemical Communications 55, no. 5 (1990): 1149–61. http://dx.doi.org/10.1135/cccc19901149.

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A powerful anion effect destabilizing alkali ion-crown complex formation has been found to operate in moderately concentrated protic (H2O, CH3OH, C2H5OH) solution, following the order HO- &gt; AcO- &gt; Cl- &gt; Br- &gt; NO3- &gt; I- &gt; NCS-. Evidence is provided that the observed effect does not originate from ion-pairing. A simple explanation is provided in terms of concordant hydrogen bond bridges of exalted stability between the gegenions, M+···OR-H···(OR-H)n···OR-H···A-. It is proposed that encapsulation of alkali ion by the macrocyclic ligand leads to a dissipation of the cation charge
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Dissertations / Theses on the topic "Hydrogen bond; Ions; Charge-transfer"

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Quayle, Michael John. "Structural studies on organic and organometallic compounds." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266881.

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Croft, Heather. "Theoretical slow atomic collision studies : charge transfer between atomic sodium and protons and the mutual neutralisation of hydrogen/deuterium and lithium ions." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318705.

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Shepherd, Juliet. "Theoretical studies of slow collisions : elastic electron scattering from positive ions, charge transfer in one-electron ion-ion systems and mutual neutralization of H⁻/D⁻ and H⁺₂." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366574.

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Yang, Kun-Yun. "The effects of the N(5) hydrogen bond and the re-face positive charge on the redox properties of flavin in the methylotrophic bacterium W3A1 electron transfer flavoprotein." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1150407209.

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Pereira, Robson Valentim. "\"Transferência de carga e ligação de hidrogênio intramolecular em derivados de 9-aminoacridina\"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-18042007-172426/.

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Neste trabalho, o corante 9-aminoacridina foi derivatizado com compostos vinílicos que possuem grupos retiradores de elétrons. A incorporação destes leva à mudanças nas propriedades fotofísicas dos derivados, tais como deslocamentos para regiões de menor energia nos espectros de absorção e emissão, sugerindo a presença de transferência de carga intramolecular (ICT). Os estudos de fluorescência resolvida no tempo confirmam este processo para os derivados. Este estado ICT possui um tempo formação na faixa de 150 – 300 ps e um tempo de vida entre 1 – 3 ns, que depende do solvente. Os derivados qu
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Naughton, Elise Michele. "Ru,Rh,Ru Supramolecular Photocatalysts within Nafion® Membranes: Ion-exchange, Photoelectrolysis and Electron Transfer Processes." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/70865.

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Perfluorosulfonate ionomers, such as Nafion® have been shown to demonstrate a profound affinity for large cationic complexes, and the study of polymer-bound cations may provide insight regarding Nafion® morphology by contrasting molecular size with existing models. The trimetallic complex, [{(bpy)2Ru(dpp)}2RhBr2] 5+, is readily absorbed by ion exchange into Na+ -form Nafion® membranes under ambient conditions. The dimensions of three different isomers of the trimetallic complex are estimated to be: 23.6 Å × 13.3 Å × 10.8 Å, 18.9 Å × 18.0 Å × 13.7 Å, and 23.1 Å × 12.0 Å × 11.4 Å, yielding an av
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Cambou, Patrick. "Rôle du twist à l'état fondamental sur l'anomalie de fluorescence double des N, N dialkylanilines para-substituées diluées en solutions liquides et solides : application au dosage des traces d'eau." Grenoble 1, 1987. http://www.theses.fr/1987GRE10045.

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Rambaud, Christophe. "Etude, par spectroscopie optique, de la délocalisation quantique de protons dans des cristaux d'acide benzoi͏̈que." Grenoble 1, 1989. http://www.theses.fr/1989GRE10103.

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Les transitions optiques des molecules de thioindigo dopant des cristaux d'acide benzoique, sont sensibles au transfert des protons par effet tunnel le long des liaisons hydrogene intradimeres de la matrice. Mesure dans le cas d'un acide carboxylique des niveaux d'energie des protons delocalises et de l'element de matrice d'effet tunnel. Sensibilite du systeme a transfert de protons aux contraintes internes et externes. Deduction des vitesses de relaxation des protons delocalises, comparaison avec des calculs theoriques indiquant l'importance des processus a plusieurs phonons dans cette relaxa
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Pal, Sushanta Kumar. "Charge Transfer And Hydrogen Bonding Interactions In Ferrocenyl Schiff Bases." Thesis, 1999. http://etd.iisc.ernet.in/handle/2005/1665.

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Schafer, David Allen. "Absolute differential cross sections for charge-transfer of keV-energy hydrogen ion and oxygen ion ions with atomic oxygen." Thesis, 1989. http://hdl.handle.net/1911/16293.

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The major constituent in the atmosphere of the Earth at altitudes between 200 and 500km is atomic oxygen.$\sp1$ Collisions involving atomic oxygen are therefore important in this region of the atmosphere. Due to the difficulty in producing atomic oxygen in the laboratory, there are very few reported measurements of scattering cross sections with an atomic oxygen target.$\sp{2-6}$ We have undertaken an experimental program designed to measure absolute differential cross sections for various collision processes involving atomic oxygen. The oxygen atoms are produced through dissociation of O$\sb2
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Book chapters on the topic "Hydrogen bond; Ions; Charge-transfer"

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Gehlen, Marcelo H., Emanuelle R. Simas, Robson V. Pereira, and Carolina A. Sabatini. "Modulation of Dye Fluorescence by Photoinduced Intramolecular Charge Transfer with Resonance-Assisted Hydrogen Bond." In Reviews in Fluorescence 2010. Springer New York, 2011. http://dx.doi.org/10.1007/978-1-4419-9828-6_6.

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Zhang, F. S., and T. R. Yu. "Reactions with Hydrogen Ions." In Chemistry of Variable Charge Soils. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097450.003.0013.

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Hydrogen ion is one kind of cation which possesses many properties common to all cations. Hydrogen ion also has its own characteristic features which are of particular significance for variable charge soils. The interactions between hydrogen ions and the surface of soil particles is the basic cause of the variability of both positive and negative surface charges of variable charge soils. The quantity of hydrogen ions in soils determines the acidity of the soil while the acidity of variable charge soils is among the strongest in all the soils. This strong acidity of variable charge soils affects many other chemical properties of the soil. In this chapter, the basic properties of hydrogen ions will be briefly discussed. Then, the products and the kinetics of the interaction between hydrogen ions and variable charge soils will be treated. The dissociation of hydrogen ions from the surface of soil particles has already been mentioned in Chapter 2. After the dissociation of an electron, a hydrogen atom becomes a proton (H+ ion). The ionization energy of hydrogen atoms is 1310 kj mol-1, whereas those of alkali metals, Li, Na, K, and Cs, are 519, 494, 419 and 377 kj mol-1, respectively. This difference in the ionization energy between hydrogen and alkali metals indicates that protons have a particularly strong affinity for electrons. Therefore, protons are apt to form a covalent bond with other atoms by sharing a pair of electrons, or to form a hydrogen bond. Because of the absence of an electronic shell, a proton has a diameter of the order of 10-13 cm, while other ions with electronic shells generally have a diameter of the order of 10-8 cm. Because a proton is so small, it is quite accessible to its neighboring ions and molecules. Therefore, there is very little steric hindrance when protons participate in chemical reactions. The above-mentioned features of proton are the basis for its particular properties. Free proton in solution is extremely unstable because it is very active. In an aqueous solution it will react with water molecules to form a hydrated proton, H3O+.
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Sawyer, Donald T., and R. J. P. Williams. "Reactivity of superoxide ion." In Oxygen Chemistry. Oxford University Press, 1992. http://dx.doi.org/10.1093/oso/9780195057980.003.0011.

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Reduction of dioxygen by electron transfer yields superoxide ion (O2-.), which has its negative charge and electronic spin density delocalized between the two oxygens. As such it has limited radical character [H-OO bond energy ΔGBF, 72 kcal]2 and is a weak Bransted base in water . . . HOO· → H+ + O2-. Kdiss, 2.0 × 10-5 (7.1) . . . The dynamics for the hydrolysis and disproportionation of O2-. in aqueous solutions have been characterized by pulse radiolysis. For all conditions the rate-limiting step is second order in O2-. concentration, and the maximum rate occurs at a pH that is equivalent to the pKa for HOO· (it decreases monotonically with further decreases in the hydrogen ion concentration).
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Atkins, Peter. "Zippers: Base Catalysis." In Reactions. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199695126.003.0023.

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A base, you should recall from Reaction 2, is the second hand clapping to the acid’s first. That is, whereas an acid is a proton donor, a base is its beneficiary as a proton acceptor. The paradigm base is a hydroxide ion, OH–, which can accept a proton and thereby become H2O. However, in the context of catalysis, the topic of this section, its role is rather different: instead of using its electrons to accept the proton, it uses them to behave as a nucleophile (Reaction 15), a searcher out of positive charge. Instead of forming a hydrogen–oxygen bond with an incoming proton, it sets the electronic fox among the electronic geese of a molecule by forming a new carbon–oxygen bond and thereby loosening the bonds to neighbouring atoms so that they can undergo rearrangement. The OH– ion in effect unzips the molecule and renders it open to further attack. Base catalysis has a lot of important applications. An ancient one is the production of soap from animal fat. To set that scene, I shall consider a simple model system, the ‘hydrolysis’ (severing apart by water) of the two components of an ester, 1 (the same compound I used in Reaction 17, a combination of acetic acid and ethanol), and then turn to soap-making itself. You saw in Reaction 17 how esters can be broken down into their components, a carboxylic acid and an alcohol, by an acid; here we see the analogous reaction in the presence of a base. To be specific, the reagent is a solution of sodium hydroxide, which provides the OH– ions that catalyse the reaction. We watch what happens when a solution of sodium hydroxide is added to an ester and the mixture is boiled. The O oxygen atoms of the ester have already ripened the molecule for nucleophilic attack by drawing some of the electron cloud away from the C atom to which they are both attached, leaving it with a partial positive charge, 2. The negatively charged OH– ion sniffs out that positive charge and jostles in to do its business.
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Bortiatynski, Jacqueline M., and Patrick G. Hatcher. "The Development of 13C Labeling and 13C NMR Spectroscopy Techniques to Study the Interaction of Pollutants with Humic Substances." In Nuclear Magnetic Resonance Spectroscopy in Environment Chemistry. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097511.003.0007.

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Modern agricultural practices have contributed to the accumulation of herbicides, pesticides and their decomposition products in the soil. These pollutants are known to interact with soil organic matter to form covalent and/or noncovalent bonding associations. The covalent bonds are thought to result from addition or oxidative coupling reactions, some of which may be catalyzed by oxidoreductive enzymes. Noncovalent associations include such interactions as ion exchange, hydrogen bonding, protonation, charge transfer, ligand exchange, coordination through metal ions, van der Waals forces, and hydrophobic bonding. The association of pollutants with soil organic matter is an area of study that is of extreme interest for two reasons. First, dissolved organic matter present in lakes and streams is known to enhance the solubility of pollutants, which poses a real threat to the quality of fresh water supplies. Therefore, if we are to predict the movement of pollutants in the water table we need to have a mechanistic understanding of their interactions with dissolved humic materials. Second, early studies had indicated that some pollutants chemically bind to humic materials, thus reducing the risk of further transport and dispersion. If this chemical binding of the pollutants is irreversible, then this process may serve as a natural means for their detoxification. Regardless of the type of association, the first task in any mechanistic study is to characterize the reaction products structurally. In the case of noncovalent binding mechanisms, studies have focused on the physical characteristics of the process and not on the structure of the associated pollutant. Association studies are used to determine the sorption kinetics and transport of pollutants as well as their association constants. These types of studies utilize various techniques such as batch sorption, gas-purge desorption, column adsorption, and miscible displacement. All of these techniques are only capable of providing quantitative information on the amount of pollutant sorbed by a substrate. The study of the covalent binding of pollutants to humic substances has utilized 14C labeling in addition to various spectrometric techniques such as ultraviolet (UV) difference, fluorescence polarization and infrared (IR) spectroscopy.
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Sposito, Garrison. "Soil Particle Surface Charge." In The Chemistry of Soils. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780190630881.003.0011.

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Structural charge arises on the surfaces of soil mineral particles in which either cation vacancies or isomorphic substitutions of cations by cations of lower valence occur. The principal minerals bearing structural charge are therefore the micas (Section 2.2), the 2:1 clay minerals (Section 2.3), or the Mn(IV) oxide, birnessite (Section 2.4). These three classes of mineral are all layer type and the cleavage surface on which their structural charge is manifest is a plane of O ions. The plane of O ions on the cleavage surface of a layer-type aluminosilicate is called a siloxane surface.This plane is characterized by hexagonal symmetry in the configuration of its constituent O ions, as shown at the top of Fig. 2.3 and, more explicitly, on the right side of Fig. 2.4, where a portion of the siloxane surface of the micas is depicted. Reactive molecular units on the surfaces of soil particles are termed surface functional groups. The functional group associated with the siloxane surface is the roughly hexagonal (strictly speaking, ditrigonalbecause the hexagonal symmetry is distorted when the tetrahedral sheet is fused to an octahedral sheet to form a layer) cavity formed by six corner-sharing silica tetrahedra. This cavity has a diameter of about 0.26 nm. The reactivity of the siloxane cavity depends on the nature of the electronic charge distribution in the layer structure. If there are no nearby isomorphic cations substitutions to create a negative charge, the O ions bordering the siloxane cavity function as an electron cloud donor that can bind molecules weakly through the van der Waals interaction. These interactions are akin to those underlying the hydrophobic interaction, discussed in Section 3.5, because the O in the siloxane surface can form only very weak hydrogen bonds with water molecules. Therefore, uncharged patches on siloxane surfaces may be considered hydrophobic regions to a certain degree, with, accordingly, an attraction for hydrophobic organic molecules. However, if isomorphic substitution of Al3+ by either Fe2+ or Mg2+ occurs in the octahedral sheet, the resulting structural charge is manifest on the siloxane cavities, as discussed in Section 2.3.
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Atkins, Peter. "Electronic Warfare: Electrophilic Substitution." In Reactions. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199695126.003.0021.

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Benzene, 1, is a hard nut to crack. The hexagonal ring of carbon atoms each with one hydrogen atom attached has a much greater stability than its electronic structure, with an alternation of double and single carbon–carbon bonds, might suggest. But for reasons fully understood by chemists, that very alternation, corresponding to a continuous stabilizing cloud of electrons all around the ring, endows the hexagon with great stability and the ring persists unchanged through many reactions. The groups of atoms attached to the ring, though, may come and go, and the reaction type responsible for replacing them is commonly ‘electrophilic substitution’. Whereas the missiles of Reaction 15 sniff out nuclei by responding to their positive electric charge shining through depleted regions of electron clouds, electrophiles, electron lovers, are missiles that do the opposite. They sniff out the denser regions of electron clouds by responding to their negative charge. Let’s suppose you want to make, for purposes you are perhaps unwilling to reveal, some TNT; the initials denote trinitrotoluene. You could start with the common material toluene, which is a benzene ring with a methyl group (–CH3) in place of one H atom, 2. Your task is to replace three of the remaining ring H atoms with nitro groups, –NO2, to achieve 3. And not just any of the H atoms: you need the molecule to have a symmetrical array of these groups because other arrangements are less stable and therefore dangerous. It is known that a mixture of concentrated nitric and sulfuric acids contains the species called the ‘nitronium ion’, NO2+, 4, and this is the reagent you will use. Before we watch the reaction itself, it is instructive to see what happens when concentrated sulfuric acid and nitric acid are mixed. If we stand, suitably protected, in the mixture, we see a sulfuric acid molecule, H2SO4, thrust a proton onto a neighbouring nitric acid molecule, HNO3. (Funnily enough, according to the discussion in Reaction 2, nitric ‘acid’ is now acting as a base, a proton acceptor! I warned you of strange fish in deep waters.) The initial outcome of this transfer is unstable; it spits out an H2O molecule which wanders off into the crowd. We see the result: the formation of a nitronium ion, the agent of nitration and the species that carries out the reaction for you.
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Liu, Z. G., and C. P. Ding. "Oxidation-Reduction Reactions." In Chemistry of Variable Charge Soils. Oxford University Press, 1997. http://dx.doi.org/10.1093/oso/9780195097450.003.0016.

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Oxidation-reduction reactions are chemical reactions caused by the transfer of electrons between two substances. These reactions occur actively in variable charge soils. This is because that under conditions of high temperature and high precipitation both the accumulation and the decomposition of organic matter proceed rapidly. The decomposition products of organic matter may release electrons, providing the necessary condition for the occurrence of reduction reactions. In particular, because the soil may have a high content of water during seasonal rainy periods, the presence of a strongly reducing condition is possible. Furthermore, large areas of variable charge soils have been cultivated for rice production. For these paddy soils there are always intensive oxidation-reduction reactions proceeding alternately. Variable charge soils have a high content of iron oxides. The content of manganese is also higher than that of constant charge soils. Thus, the soil itself possesses plenty of electron-acceptors. Besides, the high concentration of hydrogen ions in variable charge soils is favorable for the occurrence of reduction reactions. Therefore, as shall be seen in this chapter, contrary to the belief that the significance of oxidation- reduction reactions is confined chiefly to submerged soils, these reactions may play an important role in soil genesis and soil fertility for variable charge soils even under well-aerated conditions. In this chapter, after discussions on factors affecting the intensity of oxidation-reduction and interactions among various oxidation-reduction substances, the oxidation-reduction regimes of variable charge soils under different utilization conditions will be presented. Ferrous and manganous ions, two important inorganic reducing substances in soils, shall be dealt with in the next chapter. The oxidation-reduction intensity of a substance is determined by its ability to liberate or accept electrons. Therefore, electron activity in an equilibrium system may be used as an index for expressing its reduction strength. An electron has a radius of only approximately 1/20,000 of that of a hydrogen atom. Its large charge-to-size ratio prevents it from persisting in free form in aqueous systems. The ephemeral “hydrated electron” has a half-life of less than 1 msec (Bartlett and James, 1993). As a species with a potential of -2.7 V vs. the standard potential of H+/H2, it is a powerful reducing agent.
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Conference papers on the topic "Hydrogen bond; Ions; Charge-transfer"

1

Zhu, Beibei, and Hongtao Gao. "Molecular Dynamics Simulation for the Impact of N-Decanol Surfactants on the Liquid-Vapor Interface of Lithium Bromide Aqueous Solution." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22746.

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In order to investigate the effect of n-decanol, a kind of alcohol surfactants, on the absorption of water vapor into lithium bromide aqueous solution, this study focused on microscopic structure of the liquid-vapor interface of the electrolyte solution, the impact of n-decanol molecules on the interfacial properties and the absorption dynamic process employing the method of molecular dynamics simulation. The liquid-vapor configuration of lithium bromide aqueous solution added with four concentration of n-decanol can be analyzed by examining the density profile, the radial distribution functio
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Takeda, S., T. Inabe, T. Mitani, Y. Maruyama, and K. Yamaguchi. "ESR and NMR study on the charge-transfer complexes of N-Ssalicylideneanilines containing NHO hydrogen bond as a dynamic function." In International Conference on Science and Technology of Synthetic Metals. IEEE, 1994. http://dx.doi.org/10.1109/stsm.1994.834748.

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3

Han, Jiahua, and Hongtan Liu. "AB Initio Simulation on Grotthuss Mechanism." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-81340.

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Ab initio simulations on Grotthuss mechanism have been carried out. Using the simulation results together with the existing experimental data, all the popular propositions for Grotthuss mechanism, including the one recently proposed by Noam [1], have been checked. Combining with the charge distribution calculation and the movement of the positive charge center inside the protonated water cluster during the proton diffusion process, only one mechanism is shown probable, while all the other proposed mechanisms are excluded. According to this probable mechanism, the high mobility of proton inside
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Faizan, Mohd, Ziya Afroz, Mohammad Jane Alam, Sheeraz Ahmad Bhat, Shabbir Ahmad, and Afaq Ahmad. "Nature and potency interactions of the hydrogen bond through the NBO analysis for charge transfer complex between 2-amino-4-hydroxy-6-methylpyrimidine and 2,3-pyrazinedicarboxylic acid." In 2ND INTERNATIONAL CONFERENCE ON CONDENSED MATTER AND APPLIED PHYSICS (ICC 2017). Author(s), 2018. http://dx.doi.org/10.1063/1.5033245.

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