Hydrogen-bonding and dielectric response of N,N-dimethylacetamide aqueous solutions under E/M fields using molecular dynamics

Abstract

Non-equilibrium molecular dynamics (NMD) simulations of the N,N-dimethylacetamide (DMAC) aqueous solutions using a non-polarizable field have been performed in the frequency of 1GHz with the intensity of the E/M field in the range of 0 to 3×109V/m. The principal term in the radial distribution function reveals significant differences in the structure and reorientation dynamics of DMAC–H2O interaction, indicating a substantial field-induced effect of molecular structure on the hydrogen-bond network. The first hydration shell alters significantly with increasing E/M field strength. When the intensity of the E/M field is above 3×108V/m a threshold effect is observed, and the static dielectric constants decrease with increasing E/M field strength. And the molecular polarizability gradually increases when the E/M field strength increases. The average hydrogen-bond number and hydrogen-bond lifetime decline with the E/M field strength.