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Encyclopedia > Hydrogen bond
An example of a quadruple hydrogen bond between a self-assembled dimer complex reported by Meijer and coworkers.[1]
Intramolecular hydrogen bonding in acetylacetone helps stabilize the enol tautomer
Intramolecular hydrogen bonding in acetylacetone helps stabilize the enol tautomer
Carboxylic acids often form dimers in vapor phase.
Carboxylic acids often form dimers in vapor phase.

A hydrogen bond is a special type of dipole-dipole bond that exists between an electronegative atom and a hydrogen atom bonded to another electronegative atom. This type of bond always involves a hydrogen atom, thus the name. Hydrogen bonds can occur between molecules (intermolecularly), or within different parts of a single molecule (intramolecularly).[2] The typical hydrogen bond is stronger than van der Waals forces, but weaker than covalent, ionic and metallic bonds. Image File history File linksMetadata Size of this preview: 740 × 600 pixelsFull resolution (1138 × 922 pixel, file size: 235 KB, MIME type: image/jpeg) This is a picture generated from crystal structure data reported by Felix H. Beijer, Huub Kooijman, Anthony L. Spek, Rint P. Sijbesma, and E. W. Meijer... Image File history File linksMetadata Size of this preview: 740 × 600 pixelsFull resolution (1138 × 922 pixel, file size: 235 KB, MIME type: image/jpeg) This is a picture generated from crystal structure data reported by Felix H. Beijer, Huub Kooijman, Anthony L. Spek, Rint P. Sijbesma, and E. W. Meijer... An example of a molecular self-assembly through hydrogen bonds reported by Meijer and coworkers in Angew. ... Image File history File links Download high resolution version (1451x457, 11 KB)Tautomerism of Acetyl Acetone David Rovnyak Tomo Hirano Chemistry 221, 2005 Bucknell University This image is of a drawing, painting, print, or other two-dimensional work of art, and the copyright for it is most likely owned by... Image File history File links Download high resolution version (1451x457, 11 KB)Tautomerism of Acetyl Acetone David Rovnyak Tomo Hirano Chemistry 221, 2005 Bucknell University This image is of a drawing, painting, print, or other two-dimensional work of art, and the copyright for it is most likely owned by... R-phrases , S-phrases , , , Flash point 34 °C Autoignition temperature 340 °C Explosive limits 2. ... Enol (or, more officially, but less commonly: alkenol) is an alkene with hydroxyl group on one of the carbon atoms of the double bond. ... Image File history File links Download high-resolution version (1803x827, 12 KB) en:Carboxylic acid dimers. ... Image File history File links Download high-resolution version (1803x827, 12 KB) en:Carboxylic acid dimers. ... Structure of a carboxylic acid The 3D structure of the carboxyl group A space-filling model of the carboxyl group Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the formula -C(=O)OH, usually written -COOH or -CO2H. [1] Carboxylic acids are Bronsted... In physics, chemistry, and biology, intermolecular forces are forces that act between stable molecules or between functional groups of macromolecules. ... It has been suggested that this article or section be merged with electronegativity. ... This article is about the chemistry of hydrogen. ... The title given to this article is incorrect due to technical limitations. ... Covalent redirects here. ... Electron configurations of lithium and fluorine. ... Metallic bonds are found in metals like copper. ...


Intermolecular hydrogen bonding is responsible for the high boiling point of water (100 °C). This is because of the strong hydrogen bond, as opposed to other group 16 hydrides. Intramolecular hydrogen bonding is partly responsible for the secondary, tertiary, and quaternary structures of proteins and nucleic acids. Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... The chalcogens (with the ch pronounced with a hard c as in chemistry) are the name for the periodic table group 16 (old-style: VIB or VIA) in the periodic table. ... Hydride is the name given to the negative ion of hydrogen, H−. Although this ion does not exist except in extraordinary conditions, the term hydride is widely applied to describe compounds of hydrogen with other elements, particularly those of groups 1–16. ... A representation of the 3D structure of the myoglobin protein. ... In biochemistry and chemistry, the tertiary structure of a protein or any other macromolecule is its three-dimensional structure, as defined by the atomic coordinates. ... In biochemistry, many proteins are actually assemblies of more than one protein (polypeptide) molecule, which in the context of the larger assemblage are known as protein subunits. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Look up nucleic acid in Wiktionary, the free dictionary. ...

Contents

Bonding

A hydrogen atom attached to a relatively electronegative atom is a hydrogen bond donor. This electronegative atom is usually fluorine, oxygen, or nitrogen. An electronegative atom such as fluorine, oxygen, or nitrogen is a hydrogen bond acceptor, regardless of whether it is bonded to a hydrogen atom or not. An example of a hydrogen bond donor is ethanol, which has a hydrogen bonded to oxygen; an example of a hydrogen bond acceptor which does not have a hydrogen atom bonded to it is the oxygen atom on diethyl ether. Electronegativity is a measure of the ability of an atom or molecule to attract electrons in the context of a chemical bond. ... Distinguished from fluorene and fluorone. ... General Name, symbol, number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, period, block 16, 2, p Appearance colorless (gas) pale blue (liquid) Standard atomic weight 15. ... General Name, symbol, number nitrogen, N, 7 Chemical series nonmetals Group, period, block 15, 2, p Appearance colorless gas Standard atomic weight 14. ... Grain alcohol redirects here. ... This article is about the chemical compound. ...


Carbon can also participate in hydrogen bonding, especially when the carbon atom is bound to several electronegative atoms, as is the case in chloroform, CHCl3. The electronegative atom attracts the electron cloud from around the hydrogen nucleus and, by decentralizing the cloud, leaves the atom with a positive partial charge. Because of the small size of hydrogen relative to other atoms and molecules, the resulting charge, though only partial, nevertheless represents a large charge density. A hydrogen bond results when this strong positive charge density attracts a lone pair of electrons on another heteroatom, which becomes the hydrogen-bond acceptor. For other uses, see Carbon (disambiguation). ... R-phrases , , , S-phrases , Flash point Non-flammable U.S. Permissible exposure limit (PEL) 50 ppm (240 mg/m3) (OSHA) Supplementary data page Structure and properties n, εr, etc. ... A lone pair is an electron pair without bonding or sharing with other atoms. ... In the nomenclature of organic chemistry, a heteroatom (from Ancient Greek heteros, different, + atomos) is any atom that is not carbon or hydrogen, typically, but not exclusively, nitrogen, oxygen, sulfur, phosphorus or boron. ...


The hydrogen bond is often described as an electrostatic dipole-dipole interaction. However, it also has some features of covalent bonding: it is directional, strong, produces interatomic distances shorter than sum of van der Waals radii, and usually involves a limited number of interaction partners, which can be interpreted as a kind of valence. These covalent features are more significant when acceptors bind hydrogens from more electronegative donors. In chemistry, valence, also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element. ...


The partially covalent nature of a hydrogen bond raises the questions: "To which molecule or atom does the hydrogen nucleus belong?" and "Which should be labeled 'donor' and which 'acceptor'?" Usually, this is easy to determine simply based on interatomic distances in the X-H...Y system: X-H distance is typically ~1.1 Å, whereas H...Y distance is ~ 1.6 to 2.0 Å. Liquids that display hydrogen bonding are called associated liquids. The nucleus of an atom is the very small dense region, of positive charge, in its centre consisting of nucleons (protons and neutrons). ... An angstrom, angström, or Ã¥ngström (symbol Ã…) is a unit of length. ... An angstrom, angström, or Ã¥ngström (symbol Ã…) is a unit of length. ...


Hydrogen bonds can vary in strength from very weak (1-2 kJ mol−1) to extremely strong (>155 kJ mol−1), as in the ion HF2.[3] Typical values include: The hydrogendifluoride anion The hydrogendifluoride ion or, more commonly, the bifluoride ion, is the species HF2−. This centrosymmetric triatomic anion features the strongest known hydrogen bond, with a F−H length of 114 pm 1 and a bond strength of >155 kJ/mol. ...

  • F—H...:F (155 kJ/mol or 40 kcal/mol)
  • O—H...:N (29 kJ/mol or 6.9 kcal/mol)
  • O—H...:O (21 kJ/mol or 5.0 kcal/mol)
  • N—H...:N (13 kJ/mol or 3.1 kcal/mol)
  • N—H...:O (8 kJ/mol or 1.9 kcal/mol)
  • HO—H...:OH3+ (18 kJ/mol[4] or 4.3 kcal/mol) {Data obtained using molecular dynamics as detailed in the reference and should be compared to 7.9 kJ/mol, obtained using the same molecular dynamics.}

The length of hydrogen bonds depends on bond strength, temperature, and pressure. The bond strength itself is dependent on temperature, pressure, bond angle, and environment (usually characterized by local dielectric constant). The typical length of a hydrogen bond in water is 1.97 Å (197 pm). Molecular dynamics (MD) is a form of computer simulation wherein atoms and molecules are allowed to interact for a period of time under known laws of physics, giving a view of the motion of the atoms. ... Molecular dynamics (MD) is a form of computer simulation wherein atoms and molecules are allowed to interact for a period of time under known laws of physics, giving a view of the motion of the atoms. ... A dielectric is a physical model commonly used to describe how an electric field behaves inside a material. ...


Hydrogen bonds in water

Snapshot from a simulation of liquid water. The dashed blue lines from the molecule in the center of the picture represent hydrogen bonds.
Snapshot from a simulation of liquid water. The dashed blue lines from the molecule in the center of the picture represent hydrogen bonds.

The most ubiquitous, and perhaps simplest, example of a hydrogen bond is found between water molecules. In a discrete water molecule, water has two hydrogen atoms and one oxygen atom. Two molecules of water can form a hydrogen bond between them; the simplest case, when only two molecules are present, is called the water dimer and is often used as a model system. When more molecules are present, as is the case in liquid water, more bonds are possible because the oxygen of one water molecule has two lone pairs of electrons, each of which can form a hydrogen bond with hydrogens on two other water molecules. This can repeat so that every water molecule is H-bonded with up to four other molecules, as shown in the figure (two through its two lone pairs, and two through its two hydrogen atoms.) Image File history File links Size of this preview: 722 × 599 pixelsFull resolution (1354 × 1124 pixel, file size: 325 KB, MIME type: image/png) File historyClick on a date/time to view the file as it appeared at that time. ... Image File history File links Size of this preview: 722 × 599 pixelsFull resolution (1354 × 1124 pixel, file size: 325 KB, MIME type: image/png) File historyClick on a date/time to view the file as it appeared at that time. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ... Ball-and-stick model of the linear water dimer The water dimer consists of two water molecules loosely bound by a hydrogen bond. ...


Liquid water's high boiling point is due to the high number of hydrogen bonds each molecule can have relative to its low molecular mass, not to mention the great strength of these hydrogen bonds. Realistically the water molecule has a very high boiling point, melting point and viscosity compared to other similar substances not conjoined by hydrogen bonds. The reasoning for these attributes is the inability to, or the difficulty in, breaking these bonds. Water is unique because its oxygen atom has two lone pairs and two hydrogen atoms, meaning that the total number of bonds of a water molecule is up to four. For example, hydrogen fluoride—which has three lone pairs on the F atom but only one H atom—can have a total of only two bonds (ammonia has the opposite problem: three hydrogen atoms but only one lone pair). For other uses, see Liquid (disambiguation). ... Italic text This article is about the boiling point of liquids. ... The molecular mass (abbreviated Mr) of a substance, formerly also called molecular weight and abbreviated as MW, is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of carbon-12). ... For other uses, see Ammonia (disambiguation). ...

H-F...H-F...H-F

The exact number of hydrogen bonds in which a molecule in liquid water participates fluctuates with time and depends on the temperature. From TIP4P liquid water simulations at 25 °C, it was estimated that each water molecule participates in an average of 3.59 hydrogen bonds. At 100 °C, this number decreases to 3.24 due to the increased molecular motion and decreased density, while at 0 °C, the average number of hydrogen bonds increases to 3.69.[5] A more recent study found a much smaller number of hydrogen bonds: 2.357 at 25 °C.[6] The differences may be due to the use of a different method for defining and counting the hydrogen bonds. In computational chemistry, classical water models are used for the simulation of liquid water and aqueous solutions. ...


Were the bond strengths more equivalent, one might instead find the atoms of two interacting water molecules partitioned into two polyatomic ions of opposite charge, specifically hydroxide (OH) and hydronium (H3O+) (Hydronium ions are also known as 'hydroxonium' ions.) An electrostatic potential map of the nitrate ion (NO3−). Areas coloured red are lower in energy than areas coloured yellow A polyatomic ion is a molecule that bears ionic groups, that is, a molecule with a charge. ... Hydroxide is a polyatomic ion consisting of oxygen and hydrogen: OH− It has a charge of −1. ... In chemistry, hydronium is the common name for the cation H3O+ derived from protonation of water. ...

H-O H3O+

Indeed, in pure water under conditions of standard temperature and pressure, this latter formulation is applicable only rarely; on average about one in every 5.5 × 108 molecules gives up a proton to another water molecule, in accordance with the value of the dissociation constant for water under such conditions. It is a crucial part of the uniqueness of water. Temperature and air pressure can vary from one place to another on the Earth, and can also vary in the same place with time. ... In chemistry and biochemistry, a dissociation constant or an ionization constant is a specific type of equilibrium constant used for reversible reactions or processes. ...


Bifurcated and over-coordinated hydrogen bonds in water

It can be that a single hydrogen atom participates in two hydrogen bonds, rather than one. This type of bonding is called "bifurcated". It was suggested that a bifurcated hydrogen atom is an essential step in water reorientation;[7] however, the case of an oxygen lone pair participating in more than two hydrogens bonds is rarely given attention in the scientific literature.


Hydrogen bonds in DNA and proteins

Hydrogen bonding between guanine and cytosine, one of two types of base pairs in DNA.
Hydrogen bonding between guanine and cytosine, one of two types of base pairs in DNA.

Hydrogen bonding also plays an important role in determining the three-dimensional structures adopted by proteins and nucleic bases. In these macromolecules, bonding between parts of the same macromolecule cause it to fold into a specific shape, which helps determine the molecule's physiological or biochemical role. The double helical structure of DNA, for example, is due largely to hydrogen bonding between the base pairs, which link one complementary strand to the other and enable replication. Image File history File links This is a lossless scalable vector image. ... Image File history File links This is a lossless scalable vector image. ... Guanine is one of the five main nucleobases found in the nucleic acids DNA and RNA; the others being adenine, cytosine, thymine, and uracil. ... Cytosine is one of the 5 main nucleobases used in storing and transporting genetic information within a cell in the nucleic acids DNA and RNA. It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at... Base pairs, of a DNA molecule. ... The structure of part of a DNA double helix Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains the genetic instructions used in the development and functioning of all known living organisms. ... Base pairs, of a DNA molecule. ... DNA replication. ...


In proteins, hydrogen bonds form between the backbone oxygens and amide hydrogens. When the spacing of the amino acid residues participating in a hydrogen bond occurs regularly between positions i and i + 4, an alpha helix is formed. When the spacing is less, between positions i and i + 3, then a 310 helix is formed. When two strands are joined by hydrogen bonds involving alternating residues on each participating strand, a beta sheet is formed. Hydrogen bonds also play a part in forming the tertiary structure of protein through interaction of R-groups.(See also protein folding). This article is about the class of chemicals. ... Side view of an α-helix of alanine residues in atomic detail. ... Side view of an 310-helix of alanine residues in atomic detail. ... Diagram of β-pleated sheet with H-bonding between protein strands The β sheet (also β-pleated sheet) is the second form of regular secondary structure in proteins — the first is the alpha helix — consisting of beta strands connected laterally by three or more hydrogen bonds, forming a generally twisted, pleated sheet. ... Protein before and after folding. ...


A special case of intramolecular hydrogen bonds within proteins, poorly shielded from water attack and hence promoting their own dehydration, are called dehydrons. Dehydration (hypohydration) is the removal of water (hydro in ancient Greek) from an object. ... Intramolecular hydrogen bond poorly shielded from water attack, with a propensity to promote its own dehydration. ...


Symmetric hydrogen bond

A symmetric hydrogen bond is a special type of hydrogen bond in which the proton is spaced exactly halfway between two identical atoms. The strength of the bond to each of those atoms is equal. It is an example of a 3-center 4-electron bond. This type of bond is much stronger than "normal" hydrogen bonds, in fact, its strength is comparable to a covalent bond. It is seen in ice at high pressure, and also in the solid phase of many anhydrous acids such as hydrofluoric acid and formic acid at high pressure. It is also seen in the ion [F-H-F]−. Much has been done to explain the symmetric hydrogen bond quantum-mechanically, as it seems to violate the duet rule for the first shell: The proton is effectively surrounded by four electrons. Because of this problem, some consider it to be an ionic bond.


Symmetric hydrogen bonds have been observed recently spectroscopically in formic acid at high pressure (>GPa). Each hydrogen atom forms a partial covalent bond with two atoms rather than one. Symmetric hydrogen bonds have been postulated in ice at high pressure (ice-X). Low-barrier hydrogen bonds form when the distance between two heteroatoms is very small. A symmetric hydrogen bond is a special type of hydrogen bond in which the proton is spaced exactly halfway between two identical atoms. ... Formic acid (systematically called methanoic acid) is the simplest carboxylic acid. ... A Low-barrier hydrogen bond or LBHB is a special type of hydrogen bond. ...


Dihydrogen bond

The hydrogen bond can be compared with the closely related dihydrogen bond, which is also an intermolecular bonding interaction involving hydrogen atoms. These structures have been known for some time, and well characterized by crystallography; however, an understanding of their relationship to the conventional hydrogen bond, ionic bond, and covalent bond remains unclear. Generally, the hydrogen bond is characterized by a proton acceptor that is a lone pair of electrons in nonmetallic atoms (most notably in the nitrogen, and chalcogen groups). In some cases, these proton acceptors may be pi-bonds or metal complexes. In the dihydrogen bond, however, a metal hydride serves as a proton acceptor; thus forming a hydrogen-hydrogen interaction. Neutron diffraction has shown that the molecular geometry of these complexes are similar to hydrogen bonds, in that the bond length is very adaptable to the metal complex/hydrogen donor system. In chemistry, a dihydrogen bond is a kind of hydrogen bond, an interaction between a metal hydride bond and an OH or NH group or another proton donor. ... In physics, chemistry, and biology, intermolecular forces are forces that act between stable molecules or between functional groups of macromolecules. ... X-ray crystallography, also known as single-crystal X-ray diffraction, is the oldest and most common crystallographic method for determining the structure of molecules. ... Electron configurations of lithium and fluorine. ... Covalent redirects here. ... Nitrogen is the 7th element in the Periodic Table. ... The chalcogens (with the ch pronounced with a hard c as in chemistry) are the name for the periodic table group 16 (old-style: VIB or VIA) in the periodic table. ... Electron atomic and molecular orbitals, showing a Pi-bond at the bottom right of the picture. ... A complex in chemistry is a reversible association of molecules, atoms, or ions through weak non-covalent chemical bonds. ... Neutron diffraction is a crystallography technique that uses neutrons to determine the atomic structure of a material. ... Geometry of the water molecule Molecular geometry or molecular structure is the three-dimensional arrangement of the atoms that constitute a molecule, inferred from the spectroscopic studies of the compound. ...


Advanced theory of the hydrogen bond

The hydrogen bond was long a fairly mysterious object in the theoretical study of quantum chemistry and physics. However, in the early 1980s it was shown to be primarily of electrostatic origin, i.e., the hydrogen bond attraction is mainly due to the interaction of permanent dipoles and higher permanent multipoles of the molecules participating in the bond. In 1983 Buckingham and Fowler[8] modelled the interaction of a large number of hydrogen bonded van der Waals molecules by atomic hard sphere repulsions and distributed multipole interactions. They found a qualitative agreement between predicted and measured structures, which showed that their model accounted for the major effects of the hydrogen bonding. These results have been borne out by many quantum chemical calculations since then, of the perturbative as well as of the supermolecule type. Quantum field theory (QFT) is the quantum theory of fields. ... Quantum chemistry is a branch of theoretical chemistry, which applies quantum mechanics and quantum field theory to address issues and problems in chemistry. ... A magnet levitating above a high-temperature superconductor demonstrates the Meissner effect. ... A van der Waals molecule is a stable cluster consisting of two or more molecules held together by van der Waals forces or by hydrogen bonds. ...


However, until recently some controversy existed about the nature of the bond. A widely publicized article[9] claimed from interpretations of the anisotropies in the Compton profile of ordinary ice, that the hydrogen bond is partly covalent. Some NMR data on hydrogen bonds in proteins also seemed to indicate covalent bonding. However, these interpretations were refuted by Ernest R. Davidson and coworkers.[10] It is now commonly assumed that for hydrogen bonding the same effects (exchange, electrostatic, polarization, and dispersion) play a role as for "ordinary" intermolecular forces, with electrostatics plus Pauli (hard sphere) repulsion being dominant for hydrogen bonds. Look up anisotropy in Wiktionary, the free dictionary. ... Ernest R. Davidson (Born October 12, 1936 in Terre Haute, Indiana, USA) is Professor of Chemistry, University of Washington, Seattle, WA, USA. He has been awarded many honours, including:- Member of the International Academy of Quantum Molecular Science (1981). ...


Hydrogen bonding phenomena

  • Dramatically higher boiling points of NH3, H2O, and HF compared to the heavier analogues PH3, H2S, and HCl
  • Viscosity of anhydrous phosphoric acid and of glycerol
  • Dimer formation in carboxylic acids and hexamer formation in hydrogen fluoride, which occur even in the gas phase, resulting in gross deviations from the ideal gas law.
  • High water solubility of many compounds such as ammonia is explained by hydrogen bonding with water molecules.
  • Negative azeotropy of mixtures of HF and water
  • Deliquescence of NaOH is caused in part by reaction of OH- with moisture to form hydrogen-bonded H2O3- species. An analogous process happens between NaNH2 and NH3, and between NaF and HF.
  • The fact that Ice is less dense than liquid water is due to a crystal structure resulting from hydrogen bonds.

This article is about orthophosphoric acid. ... Glycerine, Glycerin redirects here. ... Structure of a carboxylic acid The 3D structure of the carboxyl group A space-filling model of the carboxyl group Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the formula -C(=O)OH, usually written -COOH or -CO2H. [1] Carboxylic acids are Bronsted... Hydrogen fluoride is a chemical compound with the formula HF. Together with hydrofluoric acid, it is the principal industrial source of fluorine and hence the precursor to many important compounds including pharmaceuticals and polymers (e. ... Isotherms of an ideal gas The ideal gas law is the equation of state of a hypothetical ideal gas, first stated by Benoît Paul Émile Clapeyron in 1834. ... This article needs more context around or a better explanation of technical details to make it more accessible to general readers and technical readers outside the specialty, without removing technical details. ... Deliquescent materials are substances (mostly salts) which have a strong affinity for moisture and will absorb relatively large amount of water from the atmosphere if exposed to it, forming a liquid solution. ...

References

  1. ^ Felix H. Beijer, Huub Kooijman, Anthony L. Spek, Rint P. Sijbesma, E. W. Meijer (1998). "Self-Complementarity Achieved through Quadruple Hydrogen Bonding". Angew. Chem. Int. Ed. 37: 75-78. doi:10.1002/(SICI)1521-3773(19980202)37:1/2%3C75::AID-ANIE75%3E3.0.CO;2-R. 
  2. ^ International Union of Pure and Applied Chemistry. "hydrogen bond". Compendium of Chemical Terminology Internet edition.
  3. ^ Emsley, J. (1980). "Very Strong Hydrogen Bonds". Chemical Society Reviews 0: 91-124. 
  4. ^ Omer Markovitch and Noam Agmon (2007). "Structure and energetics of the hydronium hydration shells". J. Phys. Chem. A 111 (12): 2253 - 2256. doi:10.1021/jp068960g. 
  5. ^ W. L. Jorgensen and J. D. Madura (1985). "Temperature and size dependence for Monte Carlo simulations of TIP4P water". Mol. Phys. 56 (6): 1381. doi:10.1080/00268978500103111. 
  6. ^ Jan Zielkiewicz (2005). "Structural properties of water: Comparison of the SPC, SPCE, TIP4P, and TIP5P models of water". J. Chem. Phys. 123: 104501. doi:10.1063/1.2018637. .
  7. ^ Damien Laage and James T. Hynes (2006). "A Molecular Jump Mechanism for Water Reorientation". Science 311: 832. doi:10.1126/science.1122154. 
  8. ^ A.D. Buckingham and P.W. Fowler (1983). "Do electrostatic interactions predict structures of van der Waals molecules?". J. Chem. Phys. 79: 6426-6428. doi:10.1063/1.445721. 
  9. ^ E.D. Isaacs, et al., Physical Review Letters vol. 82, pp 600-603 (1999)
  10. ^ T. K. Ghanty; Staroverov, V. N.; Koren, P. R.; Davidson, E. R. (2000). "Is the Hydrogen Bond in Water Dimer and Ice Covalent?". J. Am. Chem. Soc. 122: 1210-1214. doi:10.1021/ja9937019. 
  • George A. Jeffrey. An Introduction to Hydrogen Bonding (Topics in Physical Chemistry). Oxford University Press, USA (March 13, 1997). ISBN 0-19-509549-9
  • Robert H. Crabtree, Per E. M. Siegbahn, Odile Eisenstein, Arnold L. Rheingold, and Thomas F. Koetzle (1996). "A New Intermolecular Interaction: Unconventional Hydrogen Bonds with Element-Hydride Bonds as Proton Acceptor". Acc. Chem. Res. 29 (7): 348-354. doi:10.1021/ar950150s. 
  • Alexander F. Goncharov, M. Riad Manaa, Joseph M. Zaug, Richard H. Gee, Laurence E. Fried, and Wren B. Montgomery (2005). "Polymerization of Formic Acid under High Pressure". Phys. Rev. Lett. 94 (6): 065505. doi:10.1103/PhysRevLett.94.065505. 
  • F. Cordier, M. Rogowski, S. Grzesiek and A. Bax (1999). "Observation of through-hydrogen-bond (2h)J(HC') in a perdeuterated protein". J Magn Reson. 140: 510-2. 
  • R. Parthasarathi, V. Subramanian, N. Sathyamurthy (2006). "Hydrogen Bonding Without Borders: An Atoms-In-Molecules Perspective". J. Phys. Chem. (A) 110: 3349-3351. 

  Results from FactBites:
 
Hydrogen Bond (361 words)
In a water molecule the electron shell round a hydrogen atom is rather thin, and the positive charge on its nucleus shows through to the outside world, giving the hydrogen atom a small positive charge.
Hydrogen bonding can only happen in molecules that have a permenent dipole (as water does) and that also contain the highly electronegative elements fluorine, oxygen, or nitrogen.
Not all stickness of molecules is due to hydrogen bonding.
Hydrogen bonding in water (3981 words)
Hydrogen bonding occurs when an atom of hydrogen is attracted by rather strong forces to two atoms instead of only one, so that it may be considered to be acting as a bond between them [99].
An interesting way of describing the cooperative/anticooperative nature of the water dimer hydrogen bond is to use the nomenclature d'a'DAd''a'' where DA represents the donor-acceptor nature of the hydrogen bond, the d'a' represents the remaining donor-acceptor status of the donating water molecule and d''a'' represents the remaining donor-acceptor status of the accepting water molecule [852].
Hydrogen bond lifetimes are 1 - 20 ps [255] whereas broken bond lifetimes are about 0.1 ps with the proportion of 'dangling' hydrogen bonds persisting for longer than a picosecond being insignificant [849].
  More results at FactBites »

 
 

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