Unified Effect of Hydrophobic Hydration on the Dynamics and the Structure of Water Molecules in Lower Alcohol Aqueous Solutions

2011 ◽  
Vol 80 (4) ◽  
pp. 044604 ◽  
Author(s):  
Masaru Nakada ◽  
Kenji Maruyama ◽  
Osamu Yamamuro ◽  
Tatsuya Kikuchi ◽  
Masakatsu Misawa
Keyword(s):  
Aqueous Solutions ◽  
Hydrophobic Hydration ◽  
Water Molecules ◽  
Structure Of Water ◽  
Lower Alcohol

scholarly journals INFLUENCE OF HEXAMETHYLPHOSPHOTRIAMIDE MOLECULES ON WATER STRUCTURE

2017 ◽  
Vol 60 (10) ◽  
pp. 36
Author(s):  
Nikolay I. Zheleznyak
Keyword(s):  
Hydrogen Bonds ◽  
Aqueous Solutions ◽  
Structural Characteristics ◽  
Water Structure ◽  
Hydrophobic Hydration ◽  
Organic Component ◽  
Water Molecules ◽  
Polar Group ◽  
Electrolyte System ◽  
Manometric Method

The volume-manometric method was used to measure the solubility of noble gases: helium, argon, and krypton in mixtures of water with HMPA in the region of small additions of the organic component at temperatures of 283.15; 298.15 and 313.15 K. The maximum on the solubility curves is explained by the competing effect of the hydrophobic and hydrophilic hydration of the corresponding fragments of HMPA molecules. The "bond-breaking" model of water was used in the present work. According to this model the possible deformations of the hydrogen bonds are neglected. It makes possible to calculate the fractions of water molecules participating in any number of hydrogen bonds at the specified temperature. The phenomenological model of the structure of HMPA aqueous solutions is presented. On the base of experimental solubility of gases and the permittivity of solutions, it is possible to calculate the structural characteristics of diluted aqueous solutions. In the frame of the model one can determine the contribution of the effects of hydrophobic hydration to the total energy of interactions in the water-non-electrolyte system and describe the changes in water structure in aqueous solutions. It was found that at x = 0.0035 mole fraction of HMPA, there is an increase in the number of water molecules participating in four hydrogen bonds without changing the average number of hydrogen bonds per water molecule. At x = 0.005 the properties of the system are already largely determined by the influence of the polar group (P = O) of the HMPA molecule. At x = 0.0101 additions of the organic component to water lead to the redistribution of H-bonds and have to the same consequences as the increase in temperature from 298.15 to 313.15 K.Forcitation:Zheleznyak N.I. Influence of hexamethylphosphotriamide molecules on water structure. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 10. P. 36-41

Long-Term Correlations In Diffusive Motion Of Water Molecules And Rare Gas Atoms In Helium And Argon Aqueous Solutions

2015 ◽  
Vol 60 (8) ◽  
pp. 757-763 ◽  
Author(s):  
V.P. Voloshin ◽  
◽  
G.G. Malenkov ◽  
Yu.I. Naberukhin ◽  
◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Rare Gas ◽  
Water Molecules ◽  
Diffusive Motion ◽  
Rare Gas Atoms

Konkurrierende Liganden: Theophyllin als nicht- und stark koordinierender Ligand in Quecksilber(II)-Komplexen / Competing Ligands: Theophylline as Non- and Strongly Coordinating Ligand in Mercury(II) Complexes

2006 ◽  
Vol 61 (6) ◽  
pp. 758-765 ◽  
Author(s):  
Matthias Nolte ◽  
Ingo Pantenburg ◽  
Gerd Meyer
Keyword(s):  
Oxygen Atom ◽  
Water Molecule ◽  
Aqueous Solutions ◽  
Single Crystal ◽  
Coordination Polymers ◽  
Water Molecules ◽  
Slow Evaporation ◽  
Monoclinic Symmetry ◽  
X Ray ◽  
Chloride Ligand

[{Hg(CF3)2}(ThpH)(H2O)](H2O) (1), [{Hg4(Thp)4}(ClO4)4(H2O)8](H2O)4 (2), [{Hg(ThpH)2} (NO3)](NO3) (3) and {Hg(Thp)Cl}(H2O) (4) (ThpH = theophylline, C7H8N4O2) have been synthesized by slow evaporation of aqueous solutions of the mercuric salts Hg(CF3)2, Hg(ClO4)2, Hg(NO3)2, or HgCl2 and theophylline. Their crystal structures were determined on the basis of single crystal X-ray data. The coordination polymers 1 and 2 crystallize with triclinic symmetry, P1̅ (no. 2), with a = 468.8(2), b = 1256.4(5), c = 1445.5(6) pm, α = 67.15(3), β = 89.21(3), γ = 89.40(3)° and a = 833.6(1), b = 1862.7(2), c = 2182.9(2) pm, α = 111.61(1), β = 90.98(1), γ = 95.51(1)°, respectively. 3 and 4 crystallize with monoclinic symmetry, Pc (no. 7), a =1194.1(1), b=1258.8(2), c=735.5(2) pm, β =96.96(2)° and P21/n (no. 14), a=1069.0(2), b =911.6(1), c=1089.9(2) pm and β = 96.87(2)°. In 1 the theophylline molecules are non-coordinating to mercury and leave the Hg(CF3)2 molecule unchanged. Only weak electrostatic attractions to one keto-oxygen atom of theophylline and one water molecule hold this co-crystallisate together. In 2, the theophyllinate anion, Thp−, strongly coordinates with both N(7) and N(9) to HgII forming a large ring with eight Hg atoms that incorporates the water molecules. One sort of nitrate ions in 3 is weakly attached to HgII with the theophylline molecules still bound strongly through N(9). The chloride ligand and the theophyllinate ion seem to have the same strengths as ligands in 4 as they are both attached to HgII with the shortest distances possible

Effects of hydrating water molecules on the aggregation behavior of azo dyes in aqueous solutions

1991 ◽  
Vol 16 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Kunihiro Hamada ◽  
Haruhiko Nonogaki ◽  
Yoshihiro Fukushima ◽  
Baljir Munkhbat ◽  
Masaru Mitsuishi
Keyword(s):  
Aqueous Solutions ◽  
Azo Dyes ◽  
Aggregation Behavior ◽  
Water Molecules

Motions of water molecules in dilute aqueous solutions of tertiary butyl alcohol; a neutron scattering study of hydrophobic hydration

1970 ◽  
Vol 319 (1537) ◽  
pp. 189-208 ◽  
Keyword(s):  
Aqueous Solutions ◽  
Water Structure ◽  
Hydrophobic Hydration ◽  
Step Length ◽  
Solute Concentration ◽  
Butyl Alcohol ◽  
Tertiary Butyl ◽  
Self Diffusion ◽  
Dilute Aqueous Solutions ◽  
Neutron Scattering Study

Cold neutron inelastic scattering experiments have been performed on dilute aqueous solutions of (CD 3 ) 3 COH and of solutions of (CH 3 ) 3 COH in D 2 O at 21 °C. From the broadening of the quasi-elastic peak and independently determined self-diffusion coefficients ( D ), diffusive lifetimes ( c ) of H 2 O molecules have been calculated as functions of solute concentration. The product Dc is insensitive to concentration, giving a mean diffusion step length of 0.14 nm. The inelastic portion of the spectrum, reflecting lattice-like hydrogen bonding modes indicates that the solute enhances the water ‘structure’ but that such structure bears no resemblance to ice.

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