Dynamics of hydration

Armrmanto, R., Schwenk, C.F. and Rode, B.M. (2003) Structure and Dynamics of Hydrated Ag (I) Ab Initio Quantum Mechanical-Molecular Mechanical Molecular Dynamics Simulation. The Journal of Physical Chemistry A, 107, 3132-3138. 

Finally, Fig. 6.32 compares the internal dynamics of hydrated C-phycocyanin with that of the same system plus trehalose, a well known cryoprotecting disaccharide. Fig. 6.32 shows that the dynamics is slowed down by about 1.5 decades. The observation is interpreted as a slowing down of the protein dynamics due to the viscosity increase of the water shell by the added trehalose molecules. This finding is corrobated by the changes of the mean-squared-dis-... 

Building on the initial findings described in Section 4, we will acquire photoelectron images of 0CS (H20)i, cluster anions at different wavelengths in the visible and UV and investigate the dynamics of hydration and hydration-induced stabilization of... 

First And Second Shell Dynamics Of Hydrated Cations Determined By QMCF MD Simulations... 

This bimodal dynamics of hydration water is intriguing. A model based on dynamic equilibrium between quasi-bound and free water molecules on the surface of biomolecules (or self-assembly) predicts that the orientational relaxation at a macromolecular surface should indeed be biexponential, with a fast time component (few ps) nearly equal to that of the free water while the long time component is equal to the inverse of the rate of bound to free transition [4], In order to gain an in depth understanding of hydration dynamics, we have carried out detailed atomistic molecular dynamics (MD) simulation studies of water dynamics at the surface of an anionic micelle of cesium perfluorooctanoate (CsPFO), a cationic micelle of cetyl trimethy-lainmonium bromide (CTAB), and also at the surface of a small protein (enterotoxin) using classical, non-polarizable force fields. In particular we have studied the hydrogen bond lifetime dynamics, rotational and dielectric relaxation, translational diffusion and vibrational dynamics of the surface water molecules. In this article we discuss the water dynamics at the surface of CsPFO and of enterotoxin. 

H. Ohtaki and T. Radnal, Structure and Dynamics of Hydrated Ions, ... 

Ohtaki H, Radnai T (1993) Structure and dynamics of hydrated ions. Chem Rev 93(3) 1157-1204... 

Rode BM, Schwenk CF, et al (2004 b) Structure and Dynamics of Hydrated Ions - New Insights through Quantum Mechanical Simulation. J Mol Liq 110 105... 

The Role of Three-Center Hydrogen Bonds in the Dynamics of Hydration... 

DiCapua, F. M, Swaminathan, S., Beveridge, D. L. Theoretical evidence for destabilization of an a-helix by water insertion molecular dynamics of hydrated decaalanine J. Am. Chem. Soc. 1990 112, 6768-6771. 

The structures and dynamics of hydrates have been studied by both ab initio calculations24 and by a variety of experimental techniques. Hydration numbers for the most common cations and anions are known.25... 

What is the structure and the dynamics of hydrated/solvated electron in hot/supercritical water In dispersed clusters of polar liquids in nonpolar liquids In microheterogeneous media (e.g. water clusters in zeolite cavities) In mixed and complex solvents of practical importance (e.g. Ref. 107) on surfaces ... 

We have investigated the microscopic nature of water molecules in the hydration shell. The experimental, theoretical, and computer simulation studies clearly demonstrate that the dynamics of hydration water molecules are significantly different from those of bulk water. 

F. Cavatorta, N. Angelini, A. Deriu G. Albanese (2002). Appl. Phys A, 74, S504 -S506. Vibrational dynamics of hydration water in amylose. 

Ohtaki T, Radnai T (1993) Structure and dynamics of hydrated ions. Chem Rev 93 1157-1204 Olivella MA, Palacios JM, Vairavamurthy A, del Rio JC, de las Heras FXC (2002) A study of sulfur functionalities in fossil fuels using destructive- (ASTM and Py-GC-MS) and non-destructive- (SEM-EDX, XANES andXPS) techniques. Fuel 81 405-411... 

Hydration phenomena of ions in organic solvents and their roles in interfacial ion-transfer processes have been extensively discussed for many years.. As discussed in this chapter, a marked development in this field may be recognized, at least from a thermodynamic viewpoint. However, no detailed molecular pictures of hydrated ions in organic solvent have been provided yet. Further experimental and theoretical approaches seem to be required. Vibrational spectroscopic and molecular dynamics simulation studies on solvation of ions in the gas phase [70,71] would shed light on the microscopic structure and dynamics of hydrated ions in organic solvents. 

Pizzitutti F, March M, Sterpone F, Rossky PJ How protein surfaces induce anomalous dynamics of hydration water. J. Phys. Chem. B 2007,111 7584—7590. 

Wood K, Plazanet M, Gabel F, Kessler B, Oesterhelt D, Zaccai G, Weik M Dynamics of hydration water in deuterated purple membranes explored by neutron scattering. Eur. Biophys. J. 2008,37 619 26. 

The dynamics of hydration water was investigated by quasi-elastic neutronscattering (QENS) experiments in a completely deuterated penta-alanine peptide at different levels of hydration (7, 30, 50, and 90%) and of dried powder. The last... 

In this section we diseuss sueh SD studies in the aqueous DNA system. Direct probes of the dynamics of hydration with different time resolutions have been carried out by placing a probe at the surface of small pieces of DNA, such as dodecamer (or hexadecamer) duplex [5,6]. Unfortunately, however, in the case of such small DNA molecules, the native stmcture can undergo significant distortion due to the presence of the solute. This can complicate the interpretation of the results, as one would first need to understand the hydration dynamics around an undistorted DNA molecule. We shall proceed to discuss the results of SD with this caveat in mind. 

Ohtaki H, Radnai T (1993) Structure and dynamics of hydrated ions. Chem Rev 93 1157-1204 Parfenyuk VI (2002) Surface potential at the gas-aqueous solution interface. Coll J 64 588-595 Pawilkowski EM, Prausnitz JM (1983) Estimation of Setchenow constants for nonpolar gases in common salts at moderate temperatures. Ind Eng Chem Fund 22 86-90 Pitzer KS (1979) Theory ion interaction approach. In Pytkovicz RM (ed) Activity coefficients in electrolyte solutions, Vol. 1. CRC Press, Boca Raton, (Chap. 7)... 

Blauth M, PribU AB, Randolf BR, Rode BM, Hofer T8 (2010) 8tructure and dynamics of hydrated Ag+ an ab initio quantum mechanical/chaige field simulation. Chem Phys Lett 500 251-255 Bonner OD, Jumper CF (1973) Effect of ions on water stiucture. Infrared Phys 13 233-242 Buchner R, Hefter G (2(X)9) Interactions and dynamics in electrolyte solutions by dielectric spectroscopy. Phys Chem Chem Phys 11 8984-8988 Buchner R, Hefter G, Barthel J (1994) Dielectric reltixation of aqueous NaF and KF solutions. J Chem 80c Faraday Trans 90 2475-2479... 

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