Dielectric properties of 2-methoxyethanol and 1,2-dimethoxyethane: Comparison with ethylene glycol

Conformations of 1,2-Dimethoxyethane in Gas and Solution Phase from Molecular Mechanics and Monte Carlo/Stochastic Dynamics Simulations

“…The overall dipole moment of DME (rootmean-square value) is also observed to increase with increasing solvent polarity, consistent with other simulations 21 and with the interpretation of experimental results. 19 The Amber** and OPLS** force fields give very similar results in either CHCl 3 and H 2 O (shown in Table 5). Although, the absence of the GG′G conformer in one of the OPLS** simulations (300 K simulation in water) parallels reports by Andersson and Karlström 5 and Tsuzuki and co-workers, 7 who were not able to optimize this conformer in gas-phase ab initio studies, it is probably an artifact of the relatively coarse sampling employed (only 5000 snapshots were saved over the course of the simulation).…”

Viscosity of (ethane-1,2-diol + 1,2-dimethoxyethane + water) at temperatures from 263.15 K to 353.15 K

“…A typical example of mixed solvents where "structure making" effects prevail is represented by {DME (1) + W (2)} which exhibits a clear maximum centred at x 2 ∼ = 0.85 (DME : W = 1 : 6). In line with the results of NMR spectroscopy, (16) we have shown in previous studies (23,24) that the actual aggregated solvent-cosolvent complex in {DME (1) + W (2)} is represented by the 1DME · 2W adduct. The stoichiometric ratio DME : W = 1 : 6 suggests therefore the formation of a supercluster (12,17) of the type {(1DME · 2W) · (4W)}, in which one primary cluster represented by an heteroaggregated complex unit like 1DME · 2W is associated with another homoaggregated primary cluster formed by four water molecules.…”

“…In fact, in this case the corresponding ν E h data are positive, despite the destructuring properties (13) of the DME component towards the ED species as established by thermophysical (4,14,15) and NMR spectroscopic studies. (16) Accordingly, the sign of ν E should be negative, as given by the arithmetic and geometric ideal mixing models. A literature survey has also provided evidence on the drastic structural rearrangements in the (ED + W) solutions.…”

“…In these cases, E B is approximately zero, so that equation (17) reduces to (16). However, for hydroxylated solvents showing a "regular" behaviour from the point of view of the solid-liquid transition phase, i.e.…”

Segmental order parameters in a nonionic surfactant lamellar phase studied with 1H–13C solid-state NMR

“…Surprisingly, it was shown by Baciu et al that the quadrupolar splitting from heavy water in a C 12 E 5 /D 2 O system, is directly proportional to the splitting obtained from an a-deuterated surfactant. 9 Experimental results 8,[37][38][39] as well as theoretical models, 40,41 molecular dynamics 42 and Monte Carlo simulations 43 predicted that the lowest energy conformations for the -OCCOsegments correspond to a gauche conformation around the C-C bond and anti around the C-O bond. This is the dominant conformation at low temperature but with a low statistical weight over the complete set of possible conformations and it has the highest dipole moment of all conformers.…”