A simulation study of CS2 solutions in two related ionic liquids with dications and monocations
R M Lynden-Bell1, E L Quitevis2
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
The Journal of Chemical Physics
|October 12, 2018
Summary
Atomistic simulations reveal carbon disulfide (CS2) behavior in ionic liquids. Dicationic ionic liquids shift CS2’s vibrational frequencies higher, with pressure significantly influencing this effect.
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- Ionic liquids (ILs) are tunable solvents with unique properties.
- Understanding solute behavior in ILs is crucial for designing new materials and processes.
- Carbon disulfide (CS2) is a model solute for studying solvation dynamics.
Purpose of the Study:
- To investigate the atomistic behavior of carbon disulfide (CS2) in dicationic and monocationic ionic liquids.
- To understand the influence of cation valency on CS2 solvation and dynamics.
- To correlate simulation results with experimental spectroscopic data.
Main Methods:
- Atomistic molecular dynamics simulations were performed.
- Calculated low-frequency librational density of states for CS2.
- Determined diffusion rates and embedding energies of ions and CS2.
Main Results:
- CS2 librational frequencies shift to higher values in dicationic ILs compared to monocationic ILs.
- This frequency shift is highly dependent on pressure.
- CS2 molecules are positioned near imidazolium rings and butyl tails in the studied ILs.
Conclusions:
- Cation valency significantly impacts CS2 solvation dynamics in ionic liquids.
- Pressure is a critical factor modulating solute-environment interactions in ILs.
- Simulation data provides insights into experimental OHD-RIKES spectroscopy findings.
Related Concept Videos
00:42Ionic Bonds
130.8K
Overview
When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions with opposite charges. Ionic compounds are rigid and brittle when solid and may dissociate into their constituent ions in water. Covalent compounds, by contrast, remain intact unless a chemical reaction breaks them.
Opposing Charges Hold Ions Together in Ionic Compounds
Ionic bonds are reversible electrostatic interactions between ions...
When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions with opposite charges. Ionic compounds are rigid and brittle when solid and may dissociate into their constituent ions in water. Covalent compounds, by contrast, remain intact unless a chemical reaction breaks them.
Opposing Charges Hold Ions Together in Ionic Compounds
Ionic bonds are reversible electrostatic interactions between ions...
130.8K
03:10Ionic Radii
33.5K
Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it is smaller than the atom from which it is derived. For example, the covalent radius of an aluminum atom (1s22s22p63s23p1) is 118 pm, whereas the ionic radius of an Al3+ (1s22s22p6) is 68 pm. As electrons are removed from the outer valence shell, the remaining core electrons occupying smaller shells experience a greater effective nuclear...
33.5K
02:54Molecular and Ionic Solids
20.1K
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
20.1K
02:55Solubility of Ionic Compounds
68.2K
Solubility is the measure of the maximum amount of solute that can be dissolved in a given quantity of solvent at a given temperature and pressure. Solubility is usually measured in molarity (M) or moles per liter (mol/L). A compound is termed soluble if it dissolves in water.
68.2K
02:42Ionic Crystal Structures
17.0K
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...
17.0K
03:34Ionic Compounds: Formulas and Nomenclature
87.3K
An element composed of atoms that readily lose electrons (a metal) can react with an element composed of atoms that readily gain electrons (a nonmetal) to produce ions through complete electron transfer. The compound formed by this transfer is stabilized by the electrostatic attractions (ionic bonds) between the oppositely charged ions.
87.3K