Complexation Thermodynamics of Cyclodextrins in the Framework of a Molecular Size-Based Model for Nonassociative Organic Liquids That Includes a Modified Hydration-Shell Hydrogen-Bond Model for Water

In this paper, chemically modified cellulose was used instead of cellulose as it offers higher adsorption capacities, great chemical strength and good resistance to heat. As part of Phyto-Adsorption Remediation Method, citric acid modified cellulose (CAMC) was used to treat ferric ion. However, there is a large possibility that CAMC molecule might interact with water molecule that contain hydrogen bond and hence pose as a competitor to ferric acid and reduces the efficiency of CAMC in ferric ion removal. Thus, the aim of this work is to identify the most stable hydrogen bond between CAMC and water, by using a computational technique. The interaction between the water molecules and CAMC was observed by varying the volume of water molecule with modified cellulose by an expansion in amorphous region. The simulation result shows that for water loading less than 20 molecules, the interaction between water molecules and CAMC is higher at temperature 311K, whilst for water loading higher than 20 molecules, the interaction weakens at higher temperature. This work proves that water molecules have the tendency to bind to carboxyl group of glucose, to oxygen of ester and to oxygen of anhydride acid of the CAMC molecule, which might pose a competition for ferric acid removal. The calculation of coordination number has shown that the number of atoms present in the first hydration shell (of radius < 2.5Å) is more as the temperature increases from 298K to 311K, which indicates that the adsorption is better at higher temperature. For hydration shell at radius >2.5Å, cell temperature is not significant to the number of atoms present.

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Proton conduction mechanism in M3H(XO4)2 crystals: the trigonal asymmetric hydrogen bond model

Solid State Ionics ◽

10.1016/s0167-2738(01)00946-8 ◽

2001 ◽

Vol 145 (1-4) ◽

pp. 167-177 ◽

Cited By ~ 15

Author(s):

R.E. Lechner

Keyword(s):

Hydrogen Bond ◽

Conduction Mechanism ◽

Proton Conduction ◽

Bond Model

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The Effect of the Hydrogen Bond on the Dielectric Constants and Boiling Points of Organic Liquids

Journal of the American Chemical Society ◽

10.1021/ja01307a002 ◽

1935 ◽

Vol 57 (4) ◽

pp. 600-605 ◽

Cited By ~ 30

Author(s):

W. D. Kumler

Keyword(s):

Hydrogen Bond ◽

Dielectric Constants ◽

Organic Liquids ◽

Boiling Points

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Water in Hydration Shell of an Azide Ion: Structure and Dynamics of Solute-water Hydrogen Bonds and Vibrational Spectral Diffusion from First Principles Simulations At Supercritical Condition

10.26434/chemrxiv.9808391 ◽

2019 ◽

Author(s):

Anwesa Karmakar

Keyword(s):

Hydrogen Bond ◽

Hydration Shell ◽

Solvation Shell ◽

Spectral Diffusion ◽

Supercritical Condition ◽

Time Dependent ◽

Dynamics Simulation ◽

Azide Ion ◽

Hydrogen Bond Dynamics ◽

Water Hydrogen

A series of ab initio MD simulations has been carried out for aqueous azide (N3-) ion solutions at three different densities and at supercritical condition (673 K) using Car-Parrinello molecular dynamics simulation. The time dependent trajectories at three different densities have been used to analyze the hydrogen bond dynamics, residence dynamics, dangling OD bond dynamics and spectral diffusion and underlying connections between them. The time dependent frequency of both the OD and NN stretching mode has been calculated using the time series analysis of the wavelet method. The population correlation function approach has been used to compute the hydrogen bond dynamics, dangling OD bond and residence dynamics of the Sc-water both inside and outside the solvation shell of the ion. The faster hydrogen bond dynamics has been observed in the vicinity of the azide ion, however the calculated OD stretching frequency is found to show red shift in the vicinity of the azide ion indicative to the formation of stronger ion-water hydrogen bond even at the supercritical condition. The overall hydrogen bond dynamics at the supercritical condition was faster with respect to the aqueous azide ion solutions at the ambient condition.

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