Related Experiment Video
Updated: Jul 20, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Hydrophobic hydration in an orientational lattice model
Nara Guisoni1, Vera Bohomoletz Henriques
1Instituto de Pesquisa e Desenvolvimento, Universidade do Vale do Paraíba (UNIVAP), Av. Shishima Hifumi, 2911, Urbanova cep 12244-000, São José dos Campos, SP, Brazil. nara@univap.br
The Journal of Physical Chemistry. B
|August 25, 2006
Summary
This study reveals ordering in water's hydration shells using a lattice model. Solvation water shows slower energy relaxation, suggesting directional interactions are key to hydrophobic hydration mechanisms.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Understanding hydrophobic hydration is crucial for various chemical and biological processes.
- Existing models often simplify the complex interactions within water molecules and their solvation shells.
- The role of hydrogen bonding directionality in water's unique properties requires further investigation.
Purpose of the Study:
- To elucidate the microscopic mechanisms of hydrophobic hydration.
- To investigate the miscibility properties of water with both polar and nonpolar solutes.
- To explore the local structure and dynamics of water in hydration layers.
Main Methods:
- Development of a simplified lattice model for water solutions.
- Incorporation of orientational hydrogen bonding and proton distribution.
- Application of quasichemical solutions for pure and mixed systems.
- Utilizing Monte Carlo simulations to analyze hydration layer structure and dynamics.
Main Results:
- Observed novel behavior in the hydration layer: energy correlation relaxation times for solvation water exceed those of bulk water.
- Identified water particle ordering within the first hydration shell.
- Demonstrated that this ordering is dependent on the directionality of interactions, unlike nonassociating solvent models.
- Found evidence of an ordered mixed pseudophase at low temperatures for polar solutes, suggesting potential immiscibility loops.
Conclusions:
- The directionality of hydrogen bonding significantly influences water's structural and dynamic properties in hydration layers.
- The simplified lattice model effectively captures key aspects of hydrophobic hydration and solute-solvent interactions.
- The findings suggest a more ordered structure in hydration shells compared to bulk water, particularly with polar solutes.
Related Concept Videos
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
02:42Aqueous Solutions and Heats of Hydration
Water and other polar molecules are attracted to ions. The electrostatic attraction between an ion and a molecule with a dipole is called an ion-dipole attraction. These attractions play an important role in the dissolution of ionic compounds in water.
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
When ionic compounds dissolve in water, the ions in the solid separate and disperse uniformly throughout the solution because water molecules surround and solvate the ions, reducing the strong electrostatic forces between them. This process...
01:34Fluid Mosaic Model
The fluid mosaic model was first proposed as a visual representation of research observations. The model comprises the composition and dynamics of membranes and serves as a foundation for future membrane-related studies. The model depicts the structure of the plasma membrane with a variety of components, which include phospholipids, proteins, and carbohydrates. These integral molecules are loosely bound, defining the cell’s border and providing fluidity for optimal function.LipidsThe most...
01:19Fluid Mosaic Model
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...