Molecular dynamics simulation of liquid water under the influence of an external electric field

Folding of Gas-Phase Polyalanines in a Static Electric Field: Alignment, Deformations, and Polarization Effects

“…Two polyalanines have been investigated with the methods described in the previous section, namely Ala 8 and Ala 16 . As in our previous work (45), the secondary structures are characterized by the average (square) electric dipole moment AEm 2 ae and by the end-to-end distance d between the nitrogen atom in N-ter position and the hydrogen atom from the hydroxyl group in C-ter position.…”

“…Here we also use complementary order parameters, which have often been used in molecular simulation of biomolecules. 16 . The proximity of the polypeptide toward its native conformation can also be measured by a parameter x called an overlap function.…”

“…Qðz À jr ij À r nat ij jÞ; (16) where N a denotes the number of a-carbons, and r ij and r nat ij are the distances between a-carbons i and j in the current configuration and in the native state, respectively. Q is the Heaviside step function, and z ¼ 0.5 Å measures how close the structure is to the native state.…”

“…The influence of external fields on the structure and dynamics of molecular systems has been mostly investigated on water, either at the bulk level (12)(13)(14)(15)(16), or in low-dimensional wires (17)(18)(19) or finite clusters (20)(21)(22)(23)(24). In the latter case, and for small clusters having fewer than five molecules, ab initio calculations (25) have shown the preferential alignment between the dipole moments along the electric field direction as the field strength increases.…”

Effect of external electric field on nanobubbles at the surface of hydrophobic particles during air flotation

“…The results for f n were listed in Table 5 (0M), all the results show that the electric eld enhanced the strength of the hydrogen bonds when there is no CO 2 molecules existing in the system, which is consistent with Wei's work. 55 But when there is CO 2 molecules existing in the system, the results show that the electric eld decreased the strength of the hydrogen bonds. Therefore, the results show that the changes are originated mostly by the electric eld.…”