Solvation of Inorganic Salts in N,N-Dimethylformamide: A Computer Simulation Investigation
Viktor Szilágyi1, Helga Tóth Ugyonka2, Ákos György Juhász1,3
1Laboratory of Nanochemistry, Department of Biophysics and Radiation Biology, Semmelweis University, Nagyvárad tér 4, H-1089 Budapest, Hungary.
The Journal of Physical Chemistry. B
|June 10, 2026
Summary
Molecular dynamics simulations reveal inorganic salts alter N,N-dimethylformamide (DMF) structure. Cation-DMF interactions dominate, destroying DMF
Area of Science:
- Physical Chemistry
- Computational Chemistry
- Materials Science
Background:
- N,N-dimethylformamide (DMF) is crucial for applications like electrospinning.
- Understanding inorganic salt effects on DMF's local structure is vital for optimizing these applications.
Purpose of the Study:
- To investigate the impact of inorganic salts (LiCl, LiBr, MgCl2, CaCl2) on the local structure of N,N-dimethylformamide (DMF).
- To evaluate the performance of different molecular dynamics interaction models for these salt solutions.
Main Methods:
- Molecular dynamics computer simulations were employed.
- Four inorganic salts (LiCl, LiBr, MgCl2, CaCl2) were studied across their solubility ranges.
- Various interaction models were assessed, with AMBER selected for its ability to reproduce salt solubilities.
Main Results:
- Cation-DMF interactions are significantly stronger than anion-DMF interactions, disrupting DMF's hydrogen-bonding network.
- Mg2+ ions exhibit exceptionally long-lived contacts with DMF, suggesting hexacomplex formation ([Mg(DMF)6]2+).
- Li+ and Ca2+ show cation-DMF contact lifetimes around 1 ns.
Conclusions:
- The AMBER model accurately reproduces experimental properties and solubilities of the studied salt solutions.
- The cation-DMF interaction is the primary driver of structural changes in these solutions.
- Evidence strongly suggests the formation of a stable [Mg(DMF)6]2+ hexacomplex.
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