scholarly journals Spectroscopic evidence for the specific Na+ and K+ interactions with the hydrogen-bonded water molecules at the electrolyte aqueous solution surfaces

2009 ◽  
Vol 130 (13) ◽  
pp. 134710 ◽  
Author(s):  
Ran-ran Feng ◽  
Hong-tao Bian ◽  
Yuan Guo ◽  
Hong-fei Wang
Keyword(s):  
Aqueous Solution ◽  
Water Molecules ◽  
Spectroscopic Evidence ◽  
Electrolyte Aqueous Solution ◽  
Hydrogen Bonded

scholarly journals Raman Spectroscopy for the Competition of Hydrogen Bonds in Ternary (H2O–THF–DMSO) Aqueous Solutions

Molecules ◽  
2019 ◽  
Vol 24 (20) ◽  
pp. 3666
Author(s):  
Liu ◽  
Zhang ◽  
Huang ◽  
Wu ◽  
Ouyang
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bond ◽  
Raman Spectroscopy ◽  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Aqueous Solutions ◽  
Dimethyl Sulfoxide ◽  
Water Molecules ◽  
Bonding Theory ◽  
Hydrogen Bonded

The effects of hydrogen bonds on the molecular structure of water-tetrahydrofuran (H2O–THF), water-dimethyl sulfoxide (H2O–DMSO), and water-tetrahydrofuran-dimethyl sulfoxide (H2O–THF–DMSO) in binary aqueous solutions and ternary aqueous solutions were studied using Raman spectroscopy. The results indicate that in the binary aqueous solution, the addition of THF and DMSO will generate hydrogen bonds with water molecules, resulting in changes in the peak positions of S=O bonds and C–O bonds. Compared with the binary aqueous solutions, the hydrogen bonds between DMSO and THF, and the hydrogen bonds between DMSO and H2O in the ternary aqueous solutions are competitive, and the hydrogen bond competition is susceptible to water content. In addition, the formation of hydrogen bonds will destroy the fully hydrogen-bonded water and make it change to the partially hydrogen-bonded water. By fitting the spectra into the three Gaussian components assigned to water molecules with different hydrogen bonding (HB) environments, these spectral features are interpreted by a mechanism that H2O in different solution systems has equal types of water molecules with similar HB degrees-fully hydrogen-bonded H2O (FHW) and partially hydrogen-bonded H2O (PHW). The ratio of the intensity transition from FHW to PHW is determined based on Gaussian fitting. Therefore, the variation of hydrogen bond competition can be supplemented by the intensity ratio of PHW/FHW ((IC2 + IC3)/IC1). This study provides an experimental basis for enriching the hydrogen bonding theory of multivariate aqueous solution systems.

Structural Study of a new Compound Based on Acid 1,4-Cyclohexanedicarboxylic (1,4-CDC)

2010 ◽  
Vol 6 (1) ◽  
pp. 891-896
Author(s):  
Manel Halouani ◽  
M. Dammak ◽  
N. Audebrand ◽  
L. Ktari
Keyword(s):  
Aqueous Solution ◽  
Water Molecules ◽  
Carboxyl Group ◽  
X Ray Diffraction ◽  
Compound I ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters ◽  
Cyclohexanedicarboxylic Acid

One nickel 1,4-cyclohexanedicarboxylate coordination polymers, Ni2 [(O10C6H4)(COO)2].2H2O  (I), was hydrothermally synthesized from an aqueous solution of Ni (NO3)2.6H2O, (1,4-CDC) (1,4-CDC = 1,4-cyclohexanedicarboxylic acid) and tetramethylammonium nitrate. Compound (I) crystallizes in the monoclinic system with the C2/m space group. The unit cell parameters are a = 20.1160 (16) Å, b = 9.9387 (10) Å, c = 6.3672 (6) Å, β = 97.007 (3) (°), V= 1263.5 (2) (Å3) and Dx= 1.751g/cm3. The refinement converged into R= 0.036 and RW = 0.092. The structure, determined by single crystal X-ray diffraction, consists of two nickel atoms Ni (1) and Ni (2). Lots of ways of which is surrounded by six oxygen atoms, a carboxyl group and two water molecules.

NADH in Solution: A Single State

2019 ◽  
Author(s):  
Joachim Hönes ◽  
Julia Wack ◽  
Katja Schmitz
Keyword(s):  
Aqueous Solution ◽  
Base Stacking ◽  
Spectroscopic Evidence ◽  
Single State

<div>Spectroscopic evidence is presented to show that NADH in aqueous solution does not exist as a folded/unfolded equilibrium but as a single state. The molecule is folded but without base stacking between dihydronicotinamide and adenine.<br></div>

scholarly journals Cyclooctanaminium hydrogen succinate monohydrate

2012 ◽  
Vol 68 (4) ◽  
pp. o1204-o1204 ◽  
Author(s):  
Sanaz Khorasani ◽  
Manuel A. Fernandes
Keyword(s):  
Hydrogen Bonds ◽  
Water Molecule ◽  
Ammonium Cation ◽  
Water Molecules ◽  
Hydrated Salt ◽  
A Chain ◽  
Hydrogen Bonded

In the title hydrated salt, C8H18N+·C4H5O4−·H2O, the cyclooctyl ring of the cation is disordered over two positions in a 0.833 (3):0.167 (3) ratio. The structure contains various O—H.·O and N—H...O interactions, forming a hydrogen-bonded layer of molecules perpendicular to thecaxis. In each layer, the ammonium cation hydrogen bonds to two hydrogen succinate anions and one water molecule. Each hydrogen succinate anion hydrogen bonds to neighbouring anions, forming a chain of molecules along thebaxis. In addition, each hydrogen succinate anion hydrogen bonds to two water molecules and the ammonium cation.

scholarly journals Crystal structure of the new hybrid material bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate

2015 ◽  
Vol 71 (11) ◽  
pp. 1384-1387
Author(s):  
Marwen Chouri ◽  
Habib Boughzala
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Hydrogen Bonds ◽  
Room Temperature ◽  
Molar Ratio ◽  
Water Molecules ◽  
Site Symmetry ◽  
Two Dimensional ◽  
Slow Evaporation ◽  
Solution Ph

The title compound bis(1,4-diazoniabicyclo[2.2.2]octane) di-μ-chlorido-bis[tetrachloridobismuthate(III)] dihydrate, (C6H14N2)2[Bi2Cl10]·2H2O, was obtained by slow evaporation at room temperature of a hydrochloric aqueous solution (pH = 1) containing bismuth(III) nitrate and 1,4-diazabicyclo[2.2.2]octane (DABCO) in a 1:2 molar ratio. The structure displays a two-dimensional arrangement parallel to (100) of isolated [Bi2Cl10]4−bioctahedra (site symmetry -1) separated by layers of organic 1,4-diazoniabicyclo[2.2.2]octane dications [(DABCOH2)2+] and water molecules. O—H...Cl, N—H...O and N—H...Cl hydrogen bonds lead to additional cohesion of the structure.

scholarly journals Removal of Chromium from Aqueous Solution Using Modified Pomegranate Peel:Mechanistic and Thermodynamic Studies

2009 ◽  
Vol 6 (s1) ◽  
pp. S153-S158 ◽  
Author(s):  
Tariq S. Najim ◽  
Suhad A. Yassin
Keyword(s):  
Activation Energy ◽  
Solid Solution ◽  
Aqueous Solution ◽  
Adsorption Process ◽  
Batch Process ◽  
The Other ◽  
Water Molecules ◽  
Pomegranate Peel ◽  
Solution Interface ◽  
Adsorbent Surface

Modified pomegranate peel (MPGP) and formaldehyde modified pomegranate peel (FMPGP) were prepared and used as adsorbent for removal of Cr(VI) ions from aqueous solution using batch process. The temperature variation study of adsorption on both adsorbents revealed that the adsorption process is endothermic, from the positive values of ∆H˚. These values lie in the range of physisorption. The negative values of ∆G˚ show the adsorption is favorable and spontaneous. On the other hand, these negative values increases with increase in temperature on both adsorbents, which indicate that the adsorption is preferable at higher temperatures. ∆S˚ values showed that the process is accompanied by increase in disorder and randomness at the solid solution interface due to the reorientation of water molecules and Cr(VI) ions around the adsorbent surface. The endothermic nature of the adsorption was also confirmed from the positive values of activation energy, Ea, the low values of Ea confirm the physisorption mechanism of adsorption. The sticking probability, S*, of Cr(VI) ion on surface of both adsorbents showed that the adsorption is preferable due to low values of S*(0< S*< 1 ), but S*values are lower for FMPGP indicating that the adsorption on FMPGP is more preferable .

scholarly journals Structure and hydrogen bonding of the hydrated selenite and selenate ions in aqueous solution

2014 ◽  
Vol 43 (17) ◽  
pp. 6315-6321 ◽  
Author(s):  
Lars Eklund ◽  
Ingmar Persson
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Bonding ◽  
Free Electron ◽  
Electron Pair ◽  
Bound Water ◽  
Water Molecules ◽  
Hydration Sphere ◽  
Free Electron Pair

The selenite ion has an asymmetric hydration sphere with loosely electrostatically bound water molecules outside the free electron pair.

Syntheses and crystal structures of two magnesium–tetrazole compounds in salt and polymeric forms

2015 ◽  
Vol 71 (3) ◽  
pp. 222-228 ◽  
Author(s):  
Mohamed Abdellatif Bensegueni ◽  
Aouatef Cherouana ◽  
Slimane Dahaoui
Keyword(s):  
Alkaline Earth ◽  
Three Dimensional ◽  
Polymer Chains ◽  
Magnesium Ion ◽  
Water Molecules ◽  
Compound I ◽  
Hydrothermal Conditions ◽  
One Dimensional ◽  
Polymeric Chains ◽  
Hydrogen Bonded

Two alkaline earth–tetrazole compounds, namelycatena-poly[[[triaquamagnesium(II)]-μ-5,5′-(azanediyl)ditetrazolato-κ3N1,N1′:N5] hemi{bis[μ-5,5′-(azanediyl)ditetrazolato-κ3N1,N1′:N2]bis[triaquamagnesium(II)]} monohydrate], {[Mg(C2HN9)(H2O)3][Mg2(C2HN9)2(H2O)6]0.5·H2O}n, (I), and bis[5-(pyrazin-2-yl)tetrazolate] hexaaquamagnesium(II), (C5H3N6)[Mg(H2O)6], (II), have been prepared under hydrothermal conditions. Compound (I) is a mixed dimer–polymer based on magnesium ion centres and can be regarded as the first example of a magnesium–tetrazolate polymer in the crystalline form. The structure shows a complex three-dimensional hydrogen-bonded network that involves magnesium–tetrazolate dimers, solvent water molecules and one-dimensional magnesium–tetrazolate polymeric chains. The intrinsic cohesion in the polymer chains is ensured by N—H...N hydrogen bonds, which formR22(7) rings, thus reinforcing the propagation of the polymer chain along theaaxis. The crystal structure of magnesium tetrazole salt (II) reveals a mixed ribbon of hydrogen-bonded rings, of typesR22(7),R22(9) andR24(10), running along thecaxis, which are linked byR24(16) rings, generating a 4,8-cflunet.

scholarly journals Dynamics of Water Molecules in Concentrated Aqueous Solution of D-Glucose

2013 ◽  
Vol 25 (14) ◽  
pp. 8225-8226 ◽  
Author(s):  
Yong-Qiang Chen ◽  
Xiao-Ming Yang
Keyword(s):  
Aqueous Solution ◽  
Water Molecules

scholarly journals Synthesis and crystal structure of a 6-chloronicotinate salt of a one-dimensional cationic nickel(II) coordination polymer with 4,4′-bipyridine

2020 ◽  
Vol 76 (5) ◽  
pp. 599-604
Author(s):  
Nives Politeo ◽  
Mateja Pisačić ◽  
Marijana Đaković ◽  
Vesna Sokol ◽  
Boris-Marko Kukovec
Keyword(s):  
Molecular Structure ◽  
Coordination Polymer ◽  
Three Dimensional ◽  
Polymeric Chain ◽  
Water Molecules ◽  
Sulfate Heptahydrate ◽  
Synthesis And Crystal Structure ◽  
One Dimensional ◽  
Polymeric Chains ◽  
Hydrogen Bonded

A 6-chloronicotinate (6-Clnic) salt of a one-dimensional cationic nickel(II) coordination polymer with 4,4′-bipyridine (4,4′-bpy), namely, catena-poly[[[tetraaquanickel(II)]-μ-4,4′-bipyridine-κ2 N:N′] bis(6-chloronicotinate) tetrahydrate], {[Ni(C10H8N2)(H2O)4](C6H3ClNO2)2·4H2O} n or {[Ni(4,4′-bpy)(H2O)4](6-Clnic)2·4H2O} n , (1), was prepared by the reaction of nickel(II) sulfate heptahydrate, 6-chloronicotinic acid and 4,4′-bipyridine in a mixture of water and ethanol. The molecular structure of 1 comprises a one-dimensional polymeric {[Ni(4,4′-bpy)(H2O)4]2+} n cation, two 6-chloronicotinate anions and four water molecules of crystallization per repeating polymeric unit. The nickel(II) ion in the polymeric cation is octahedrally coordinated by four water molecule O atoms and by two 4,4′-bipyridine N atoms in the trans position. The 4,4′-bipyridine ligands act as bridges and, thus, connect the symmetry-related nickel(II) ions into an infinite one-dimensional polymeric chain extending along the b-axis direction. In the extended structure of 1, the polymeric chains of {[Ni(4,4′-bpy)(H2O)4]2+} n , the 6-chloronicotinate anions and the water molecules of crystallization are assembled into an infinite three-dimensional hydrogen-bonded network via strong O—H...O and O—H...N hydrogen bonds, leading to the formation of the representative hydrogen-bonded ring motifs: tetrameric R 2 4(8) and R 4 4(10) loops, a dimeric R 2 2(8) loop and a pentameric R 4 5(16) loop.

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