Molecular association in liquids II. A theory of the structure of water

1951 ◽  
Vol 205 (1081) ◽  
pp. 163-178 ◽  
Keyword(s):  
Hydrogen Bond ◽  
Dielectric Constant ◽  
Distribution Function ◽  
Hydrogen Bonds ◽  
Structural Changes ◽  
Simple Expression ◽  
Water Molecules ◽  
Structure Of Water ◽  
Bending Force ◽  
Electrostatic Calculations

Previous theories of the structure of liquid water have either placed undue emphasis on crystalline structures or have postulated that too many hydrogen bonds connecting neigh­bouring molecules are broken. In this paper a theory is developed in which the majority of hydrogen bonds are regarded as distorted rather than as broken. The structural changes are examined quantitatively with the aid of a simple expression for the energy of a bent hydrogen bond. It is shown that the use of a bending force constant consistent with electrostatic calculations on simple models of water molecules leads to a satisfactory quantitative explana­tion of the observed radial distribution function, the discontinuity in density associated with the melting of ice, and the observed values of the dielectric constant of water.

scholarly journals Crystal structure and hydrogen bonding in the water-stabilized proton-transfer salt brucinium 4-aminophenylarsonate tetrahydrate

2016 ◽  
Vol 72 (5) ◽  
pp. 751-755 ◽  
Author(s):  
Graham Smith ◽  
Urs D. Wermuth
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Proton Transfer ◽  
Network Structure ◽  
Three Dimensional ◽  
Water Molecules ◽  
Arsanilic Acid ◽  
Dimensional Network

In the structure of the brucinium salt of 4-aminophenylarsonic acid (p-arsanilic acid), systematically 2,3-dimethoxy-10-oxostrychnidinium 4-aminophenylarsonate tetrahydrate, (C23H27N2O4)[As(C6H7N)O2(OH)]·4H2O, the brucinium cations form the characteristic undulating and overlapping head-to-tail layered brucine substructures packed along [010]. The arsanilate anions and the water molecules of solvation are accommodated between the layers and are linked to them through a primary cation N—H...O(anion) hydrogen bond, as well as through water O—H...O hydrogen bonds to brucinium and arsanilate ions as well as bridging water O-atom acceptors, giving an overall three-dimensional network structure.

scholarly journals 2,2′-Bipyridin-1-ium hemioxalate oxalic acid monohydrate

IUCrData ◽  
2018 ◽  
Vol 3 (8) ◽  
Author(s):  
Błażej Dziuk ◽  
Anna Jezuita
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Oxalic Acid ◽  
Water Molecule ◽  
Title Compound ◽  
Water Molecules ◽  
Asymmetric Unit ◽  
Compound C ◽  
Oxalic Acids

The asymmetric unit of the title compound, C10H9N2 +·0.5C2O4 2−·C2H2O4·H2O, consists of a 2,2′-bipyridinium cation, half an oxalate dianion, one oxalic acid and one water molecule. One N atom in 2,2′-bipyridine is unprotonated, while the second is protonated and forms an N—H...O hydrogen bond. In the crystal, the anions are connected with surrounding acid molecules and water molecules by strong near-linear O—H...O hydrogen bonds. The water molecules are located between the anions and oxalic acids; their O atoms participate as donors and acceptors, respectively, in O—H...O hydrogen bonds, which form sheets arranged parallel to the ac plane.

scholarly journals Engineering short, strong hydrogen bonds in urea di-carboxylic acid complexes

CrystEngComm ◽  
2014 ◽  
Vol 16 (35) ◽  
pp. 8177-8184 ◽  
Author(s):  
Andrew O. F. Jones ◽  
Charlotte K. Leech ◽  
Garry J. McIntyre ◽  
Chick C. Wilson ◽  
Lynne H. Thomas
Keyword(s):  
Hydrogen Bond ◽  
Carboxylic Acid ◽  
Hydrogen Bonds ◽  
Neutron Diffraction ◽  
Structural Changes ◽  
Acid Amide ◽  
Molecular Complexes ◽  
Temperature Dependent ◽  
X Ray ◽  
Methyl Substitution

The persistence of the acid⋯amide heterodimer and the effect of methyl substitution on the short strong O–H⋯O hydrogen bond is investigated in urea and methylurea di-carboxylic acid molecular complexes. Temperature dependent structural changes are also reported utilising X-ray and neutron diffraction in tandem.

scholarly journals 2-(Trimethylazaniumyl)ethyl hydrogen phosphate (phosphocholine) monohydrate

2014 ◽  
Vol 70 (5) ◽  
pp. o549-o549
Author(s):  
Yohsuke Nikawa ◽  
Kyoko Fujita ◽  
Keiichi Noguchi ◽  
Hiroyuki Ohno
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Torsion Angle ◽  
Title Compound ◽  
Water Molecules ◽  
Zigzag Chain ◽  
Hydrogen Phosphate ◽  
Compound C ◽  
Phosphate Groups

In the crystal structure of the title compound, C5H14NO4P·H2O, the zwitterionic phosphocholine molecules are connected by an O—H...O hydrogen bond between the phosphate groups, forming a zigzag chain along theb-axis direction. The chains are further connected through O—H...O hydrogen bonds involving water molecules, forming a layer parallel to (101). Three and one C—H...O interactions are also observed in the layer and between the layers, respectively. The conformation of the N—C—C—O backbone isgauchewith a torsion angle of −75.8 (2)°

Redetermination of rifampicin pentahydrate revealing a zwitterionic form of the antibiotic

2012 ◽  
Vol 68 (5) ◽  
pp. o209-o212 ◽  
Author(s):  
Barbara Wicher ◽  
Krystian Pyta ◽  
Piotr Przybylski ◽  
Ewa Tykarska ◽  
Maria Gdaniec
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Amide Group ◽  
Water Molecules ◽  
Acta Cryst ◽  
Oh Groups ◽  
Zwitterionic Form ◽  
The Family

Rifampicin belongs to the family of naphthalenic ansamycin antibiotics. The first crystal structure of rifampicin in the form of the pentahydrate was reported in 1975 [Gadret, Goursolle, Leger & Colleter (1975).Acta Cryst.B31, 1454–1462] with the rifampicin molecule assumed to be neutral. Redetermination of this crystal structure now shows that one of the phenol –OH groups is deprotonated, with the proton transferred to a piperazine N atom, confirming earlier spectroscopic results that indicated a zwitterionic form for the molecule, namely (2S,12Z,14E,16S,17S,18R,19R,20R,21S,22R,23S,24E)-21-acetyloxy-6,9,17,19-tetrahydroxy-23-methoxy-2,4,12,16,18,20,22-heptamethyl-8-[(E)-N-(4-methylpiperazin-4-ium-1-yl)formimidoyl]-1,11-dioxo-1,2-dihydro-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-5-olate pentahydrate, C43H58N4O12·5H2O. The molecular structure of this antibiotic is stabilized by a system of four intramolecular O—H...O and N—H...N hydrogen bonds. Four of the symmetry-independent water molecules are arrangedviahydrogen bonds into helical chains extending along [100], whereas the fifth water molecule forms only one hydrogen bond, to the amide group O atom. The rifampicin molecules interactviaO—H...O hydrogen bonds, generating chains along [001]. Rifampicin pentahydrate is isostructural with recently reported rifampicin trihydrate methanol disolvate.

scholarly journals (E)-4-Methoxy-N′-[(6-methyl-4-oxo-4H-chromen-3-yl)methylidene]benzohydrazide monohydrate

2014 ◽  
Vol 70 (7) ◽  
pp. o784-o784 ◽  
Author(s):  
Yoshinobu Ishikawa ◽  
Kohzoh Watanabe
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Benzene Ring ◽  
Dihedral Angle ◽  
Dihedral Angles ◽  
Water Molecules ◽  
Stacking Interactions ◽  
Solvent Water ◽  
Centroid Distance

In the title hydrate, C19H16N2O4·H2O, the 4H-chromen-4-one segment is slightly twisted, with a dihedral angle between the two six-membered rings of 3.30 (5)°. The dihedral angles between the plane of the pyranone ring and the hydrazide plane and between the planes of the pyranone ring and the benzene ring of thep-methoxybenzene unit are 26.69 (4) and 2.23 (3)°, respectively. The molecule is connected to the solvent water molecule by an N—H...O hydrogen bond. In the crystal, there are π–π stacking interactions between centrosymmetrically related pyranone rings [centroid–centroid distance = 3.5394 (9) Å], as well as bridges formed by the water moleculesviaO—H...O hydrogen bonds.

scholarly journals Crystal water as the molecular glue for obtaining different co-crystal ratios: the case of gallic acid tris-caffeine hexahydrate

2018 ◽  
Vol 74 (4) ◽  
pp. 559-562
Author(s):  
L. Vella-Zarb ◽  
U. Baisch
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Gallic Acid ◽  
Carbonyl Oxygen ◽  
Crystalline Solid ◽  
Water Molecules ◽  
Crystal Water ◽  
Classical Hydrogen Bond ◽  
Additional Hydrogen

The crystal structure of the hexahydrate co-crystal of gallic acid and caffeine, C7H6O5·3C8H10N4O2·6H2O or GAL3CAF·6H2O, is a remarkable example of the importance of hydrate water acting as structural glue to facilitate the crystallization of two components of different stoichiometries and thus to compensate an imbalance of hydrogen-bond donors and acceptors. The water molecules provide the additional hydrogen bonds required to form a crystalline solid. Whereas the majority of hydrogen bonds forming the intermolecular network between gallic acid and caffeine are formed by crystal water, only one direct classical hydrogen bond between two molecules is formed between the carboxylic oxygen of gallic acid and the carbonyl oxygen of caffeine with d(D...A) = 2.672 (2) Å. All other hydrogen bonds either involve crystal water or utilize protonated carbon atoms as donors.

scholarly journals (S,Z)-3-Phenyl-2-[(1,1,1-trichloro-7-methoxy-2,7-dioxohept-3-en-4-yl)amino]propanoic acid monohydrate

2014 ◽  
Vol 70 (2) ◽  
pp. o169-o170
Author(s):  
Alex Fabiani Claro Flores ◽  
Juliano Rosa de Menezes Vicenti ◽  
Lucas Pizzuti ◽  
Patrick Teixeira Campos
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Title Compound ◽  
Organic Molecule ◽  
Organic Molecules ◽  
Propanoic Acid ◽  
Water Molecules ◽  
Solvent Water ◽  
Compound C

In the title compound, C17H18Cl3NO5·H2O, intramolecular N—H...O and C—H...Cl hydrogen bonds formS(6) andS(5) ring motifs, respectively. The chiral organic molecule is connected to the solvent water molecule by a short O—H...O hydrogen bond. In the crystal, a weak C—H...Cl interaction connects the organic molecules along [100] while the water molecules act as bridges between the organic molecules in both the [100] and [010] directions, generating layers parallel to theabplane.

Crystal structure of vardenafil hydrochloride trihydrate, C23H33N6O4SCl (H2O)3

2018 ◽  
Vol 33 (4) ◽  
pp. 319-326
Author(s):  
Austin M. Wheatley ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Nitrogen Atom ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Density Functional ◽  
Strong Hydrogen Bond ◽  
Water Molecules ◽  
Ring Nitrogen ◽  
Intramolecular Hydrogen

The crystal structure of vardenafil hydrochloride trihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Vardenafil hydrochloride trihydrate crystallizes in space group C2/c (#15) with a = 34.78347(16), b = 11.56752(4), c = 14.69308(5) Å, β = 93.3410(4), V = 5901.839(30) Å3, and Z = 8. The fused ring system and the phenyl ring are nearly co-planar; the interplanar angle between them is 6.0°. Two intramolecular hydrogen bonds help determine this conformation. These planes stack along the c-axis. The side chains of these ring systems have a large Uiso and are neighbors in the stacks. Along the a-axis, these stacks are separated by hydrophilic layers of chloride, water molecules, and the positively charged nitrogen atoms of the vardenafil cation. Hydrogen bonds are prominent in the crystal structure. The protonated nitrogen atom forms a strong hydrogen bond to the chloride anion. The water molecules form a hexagon, making hydrogen bonds with themselves, as well as the C1 and a ring nitrogen atom. These discrete hydrogen bonds form a cluster, and there is no extended hydrogen bond network. There are many C–H⋯Cl, C–H⋯O, and C–H⋯N hydrogen bonds, which (although individually weak) contribute significantly to the crystal energy. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1620.

scholarly journals 2,2′,2′′,2′′′-(1,4-Phenylenedinitrilo)tetraacetic acid dihydrate

2012 ◽  
Vol 68 (6) ◽  
pp. o1623-o1623
Author(s):  
Juanzhi Yan ◽  
Ling Ma ◽  
Miaoli Zhu ◽  
Xiangdong Zhang ◽  
Chunhua Ge
Keyword(s):  
Hydrogen Bond ◽  
Acetic Acid ◽  
Hydrogen Bonds ◽  
Organic Molecule ◽  
Organic Molecules ◽  
Dihedral Angles ◽  
Water Molecules ◽  
Inversion Symmetry ◽  
Tetraacetic Acid ◽  
Compound C

In the title compound, C14H16N2O8·2H2O, the complete organic molecule is generated by crystallographic inversion symmetry. The dihedral angles between the aniline ring and the acetic acid groups are almost identical, viz. 82.61 (7) and 80.33 (7)°. In the crystal, O—H...O hydrogen bonds link the organic molecules and water molecules, forming zigzag chains the c axis. An intramolecular O—H...O hydrogen bond is also observed.

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