Acetonitrile

About: Acetonitrile is a research topic. Over the lifetime, 11298 publications have been published within this topic receiving 175275 citations. The topic is also known as: cyanomethane & ethyl nitrile.

The Solvation of Acetonitrile

Abstract: Acetonitrile is an extremely important solvent and cosolvent. Despite this, we have no general picture of the nature of mixed liquids containing acetonitrile applicable across-solvent families. We consider the properties of acetonitrile dissolved in 33 solvents, focusing on interpretation of the environment-sensitive solvent shift, Δν, of its CN stretch frequency, ν2. The two major models (dispersive and specific solvation) which have been proposed to interpret Δν are based on diverse experiments with incompatible conclusions. We ascertain the robust features of these models and combine them into a new one in which solvent−solvent and solvent−solute forces compete to determine the structure of the solution and hence Δν. First, Δν is analyzed in terms of solvent repulsive and dielectric effects combined with specific solvation effects. To interpret this specific solvation, 95 MP2 or B3LYP calculations are performed to evaluate structures and CN frequency shifts for CH3CN complexed with one molecule of eith...

Reactivities of Some Electrogenerated Organic Cation Radicals in Room-Temperature Ionic Liquids: Toward an Alternative to Volatile Organic Solvents?

Abstract: Four different ionic liquids, based on 1-alkyl-3-methylimidazolium or quaternary ammonium cations, were used as reaction media for several typical electrochemical reactions with a strict control of the residual water concentration. The oxidation of organic molecules (anthracene, naphthalene, durene, 1,4-dithiafulvene, and veratrole) for which the cation radicals undergo first and second-order kinetics reactions were investigated in ionic liquids and compared with their behavior in acetonitrile. From the analysis of the voltammetric current responses, the reaction mechanism was established and the thermodynamic and kinetics parameters were extracted. The most interesting result is that the nature of investigated mechanisms is almost unchanged in ionic liquids as compared with conventional organic media. A decrease of the electron-transfer kinetics from the aromatic molecules to the electrode (around 1 order of magnitude) is observed for all of the studied molecules, indicating an higher solvent reorganizat...

Short-chain alcohols strip X-type ligands and quench the luminescence of PbSe and CdSe quantum dots, acetonitrile does not.

Abstract: The effect of short-chain alcohols and acetonitrile on the ligand shell composition and the photoluminescence quantum yield of purified PbSe and CdSe quantum dots is analyzed by solution NMR and photoluminescence spectroscopy. We find that short-chain alcohols induce the release of X-type carboxylate ligands with a concurrent reduction of the photoluminescence quantum yield, while acetonitrile does not. We interpret this difference in terms of the protic or aprotic character of both nonsolvents, where only the protic alcohols can provide the protons needed to desorb carboxylate ligands. We find similar differences between short-chain alcohols and acetonitrile when used as nonsolvents during the purification of crude synthesis products, a result stressing the importance of using aprotic nonsolvents for nanocrystal purification or processing.