Apparently, the enhancement of dipole-dipole interactions under the predominantly acidic additive was not generally advantageous to the resolution of fluoroquinolone-based antibiotics on the phenylethyl-bonded phase under nonaqueous elution.
This could be accomplished by adjusting rather than enhancing the degree of dipole-dipole interactions by altering the volume of acidic or basic additive in the mobile phase.
Note that the acidity of both analyte and silanol group and thus the dipole-dipole interaction are enhanced in acetonitrile .
Two small peaks of increasing strength with increasing concentration appear at X ~ 475 and 760 nm because of the long range dipole-dipole interactions near a dielectric surface [25, 26].
The peaks at 490 and 830 nm can be attributed to the long range dipole-dipole interactions. Due to particle size, the long range interaction resonance peaks become slightly red-shifted as compared to their smaller diameter counterparts .
Theoretically, Kalia and Vashishta (1981) and Zangi and Rice (1998) studied the melting transition of a colloidal monolayer using dipole-dipole interactions and a Marcus-Rice potential, respectively, with molecular dynamics (MD) simulations.
Hurd's results established Pieranski's suggestions (Pieranski, 1980) concerning dipole-dipole interactions at large separations between interfacial colloidal particles on a firm theoretical basis, and clarified the effect of the electrostatic interactions.
We used Hurd's asymptotic pair potential, which combines the screened Coulombic and dipole-dipole interactions. It is noteworthy that the results of our Monte Carlo simulations qualitatively predict the particle configurations observed by both Pieranski (1980) (for air-water surfaces) and Nikolaides et al.
He showed that the electrostatic interaction between charged interfacial colloidal particles is dominated by the screened-Coulomb contribution, which decays exponentially at small separations and by an algebraic dipole-dipole interaction at large separations: