Solvents Having High Dielectric Constants. II. Solutions of Alkali Halides in N-Methylacetamide from 30 to 60°^1a,b

Abstract

RECEIVED AUGCST 30, 1934 Conductances, densities and viscosities of solutions of lithium chloride and of potassium and sodium chlorides, bromides and iodides in N-methylacetamide have been measured within the temperature range from 30 to 60" for concentrations which ranged from 5 X 10-4 to 1.0 or 2.0 molar. Kohlrausch plots for all of the systems exhibit relatively good agreement with the Onsager limiting equation to concentrations of 0.01 molar or more. Plots of the product of the equivalent conductance and the square root of the relative viscosity of the solution versus the square root of the concentration yield straight lines to 0.3 molar or above. The Kohlrausch law of independent ion mobilities is shown to be valid in these solutions.

Medium decoupling of dynamics at temperatures ∼100 K above glass-transition temperature: A case study with (acetamide + lithium bromide/nitrate) melts

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Acetamide has been one of the most frequently used amides because of its unique solvating power [14][15][16][17][18][19] which arises due to the presence of several functional groups, high molecular dipole moment (3.7 D), and fairly large static dielectric constant (ε 0 ≈ 60) 17 in molten state (melting point ∼353 K, boiling point ∼495 K). These interesting solvent properties coupled with a wide thermal window have made molten mixtures of (acetamide + electrolyte) to be used not only as reaction media in chemical industry but also as materials for electrochemical applications at elevated temperatures.…”

Reoptimized interaction parameters for the peptide‐backbone model compound N‐methylacetamide in the GROMOS force field: Influence on the folding properties of two beta‐peptides in methanol

“…[4–6] The calibration against pure‐liquid properties for this compound at P = 1 bar must be performed slightly above room temperature, considering that the melting point of NMA is T m = 303.5 K at this pressure. [7] The liquid phase of pure NMA is known for its very high static relative dielectric permittivity[8, 9] ( $\varepsilon _{{\rm liq}} = 139.5$ at 333 K) and for the formation of hydrogen‐bonded microclusters,[10, 11] stabilized by strong NH···O hydrogen bonds as well as weaker CH···O interactions, sometimes referred to in the literature as “improper” hydrogen bonds. [12] The resulting parameter set, combining 53A6 OXY with the new amide parameters, will be referred to as 53A6 OXY+A .…”

Autoprotolysis Constants of Water–N-Methylacetamide Mixtures. A New Application of the Hammett Relationship to Acidity Constants

“…However, because the dielectric constant of the mixed organic-water solvents tested up until now has been less than that of water, it was desirable to verify the theory with solvent mixtures having a dielectric constant greater than 80. Then, we have chosen mixtures of water with N-methylacetamide, which has a dielectric constant of 178.9 at 30' (5,6). Such solvent mixtures are also of interest for comparison with water -dimethyl sulfoxide mixtures (7,8).…”