Quadrupolar Relaxation of 27Al in Aqueous Solution. III. Discussion on Motions of Hydration Water Molecules

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.

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

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989015019933 ◽

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.

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Dynamics and mechanism of ultrafast water–protein interactions

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1602916113 ◽

2016 ◽

Vol 113 (30) ◽

pp. 8424-8429 ◽

Cited By ~ 77

Author(s):

Yangzhong Qin ◽

Lijuan Wang ◽

Dongping Zhong

Keyword(s):

Protein Interactions ◽

Hydration Shell ◽

Water Dynamics ◽

Side Chain ◽

Water Molecules ◽

Ultrafast Dynamics ◽

Hydration Water ◽

Water Side ◽

Dynamics And Function ◽

And Function

Protein hydration is essential to its structure, dynamics, and function, but water–protein interactions have not been directly observed in real time at physiological temperature to our awareness. By using a tryptophan scan with femtosecond spectroscopy, we simultaneously measured the hydration water dynamics and protein side-chain motions with temperature dependence. We observed the heterogeneous hydration dynamics around the global protein surface with two types of coupled motions, collective water/side-chain reorientation in a few picoseconds and cooperative water/side-chain restructuring in tens of picoseconds. The ultrafast dynamics in hundreds of femtoseconds is from the outer-layer, bulk-type mobile water molecules in the hydration shell. We also found that the hydration water dynamics are always faster than protein side-chain relaxations but with the same energy barriers, indicating hydration shell fluctuations driving protein side-chain motions on the picosecond time scales and thus elucidating their ultimate relationship.

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

E-Journal of Chemistry ◽

10.1155/2009/804256 ◽

2009 ◽

Vol 6 (s1) ◽

pp. S153-S158 ◽

Cited By ~ 2

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 .

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Ein Wasserstoffisotopieeffekt im CuSO4 * 5H2O

Zeitschrift für Naturforschung A ◽

10.1515/zna-1969-1007 ◽

1969 ◽

Vol 24 (10) ◽

pp. 1502-1511

Author(s):

Karl Heinzinger

Keyword(s):

Water Vapor ◽

Aqueous Solutions ◽

Separation Factor ◽

Room Temperature ◽

Copper Ion ◽

Hydrogen Isotopes ◽

Bulk Water ◽

Water Molecules ◽

Hydration Water ◽

Sulfate Solutions

Abstract There are two kinds of water in CuSO4·5H2O differing by their binding in the crystal. The oxygen of four water molecules is bonded to the copper ion, that of the fifth molecule is hydrogen bonded. It is shown that the D/H ratios of these two kinds of water differ by 5.7%, the light isotope being enriched in the water molecules coordinated with the copper ion. The results show that there is no exchange of the hydrogen isotopes during the time needed for dehydration at room temperature which takes several days. The assumption has been confirmed that the water coordinated with the copper ion leaves the crystal first on dehydration at temperatures below 50 °C. Additional measurements of the separation factor for the hydrogen isotopes between water vapor and copper sulfate solutions allow conclusions on the fractionation of the hydrogen isotopes between bulk water and hydration water in aqueous solutions.

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

Dalton Transactions ◽

10.1039/c3dt53468e ◽

2014 ◽

Vol 43 (17) ◽

pp. 6315-6321 ◽

Cited By ~ 22

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.

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

Asian Journal of Chemistry ◽

10.14233/ajchem.2013.14641 ◽

2013 ◽

Vol 25 (14) ◽

pp. 8225-8226 ◽

Cited By ~ 1

Author(s):

Yong-Qiang Chen ◽

Xiao-Ming Yang

Keyword(s):

Aqueous Solution ◽

Water Molecules

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Supramolecular Complexes of Cucurbiturils with Second Group Metal Salts and Hydrates and Histamine

INEOS OPEN ◽

10.32931/io2109a ◽

2021 ◽

Vol 4 ◽

Author(s):

Yu. A. Borisov ◽

◽

S. S. Kiselev ◽

Keyword(s):

Aqueous Solution ◽

Density Functional Theory ◽

Density Functional ◽

Metal Salts ◽

Supramolecular Complexes ◽

Water Molecules ◽

Functional Theory ◽

Guest Molecules ◽

First Time ◽

Formation Energies

The interaction of cucurbiturils (Q6, Q7, and Q8) with Ca and Ba chlorides and iodides are studied for the first time by density functional theory. The thermodynamic parameters for the formation of host–guest complexes are calculated. The structures of complexes of Q6 and Q7 with one and two guest molecules are established. The energy parameters for the transfer of Be2+ and Ba2+ cations from an aqueous solution into the cavity of Q7 containing n water molecules are defined. The dependences of the formation energies for complexes Q7WnBe2+ and Q7WnBa2+ on the number of water molecules are shown to be parabolic, with the energy minima at n = 5 and n = 6, respectively. It is found that Q7 can form in an aqueous solution supramolecular complexes with protonated histamine (HA) and neutral histamine in the presence of Ca2+ ions.

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