Frequency Behavior of the Electro-optical Effect from Colloid Particles in Polyelectrolyte Solutions with Counterion Mixtures

Electric Properties of Adsorbed Polystyrenesulfonate

“…Although a slow dipole moment due to the polarization of monovalent counterions along the molecular axes is found to cause the anomalous signal at the reversal of the electric field (33), the origin of the saturable ionic induced dipole moment is still unclear according to Yamaoka et al (34). Proportionality to the first power of the electric field strength is shown for the low-frequency electrooptical effect in oxide suspensions, stabilized by polyelectrolyte adsorption (6). The effect is attributed to polarization of bound counterions with a relaxation time not far from the rotational relaxation time of the polymer-coated oxide particles.…”

“…This has a shorter relaxation time as compared with the rotational relaxation time of the polymer-coated colloid particle, so that discrimination of the two low-frequency effects is possible. In analogy with the polyelectrolyte relaxation spectroscopy (25), the three electro-optical effects in stabilized suspensions are denoted the RF, LF, and HF effects, i.e., the rotational, low-, and high-frequency effects (6).…”

Electric Properties and Conformation of Polyethylenimine at the Hematite–Aqueous Solution Interface

“…The electro-optical effect is defined as a Å (I E 0 I 0 )/I 0 , where I E and I 0 are the intensities of scattered light when an electric field of strength E is The decreased frequency relaxation of the kilohertz electro-suspension of a- adsorption, is related to polarization of loosely bound counterions along the polyion surface (6,(13)(14)(15). optical effect rise again due to the increased charge density The electro-optical effect decays exponentially with time of the colloid-polymer complex.…”

Alignment of Rod-Shaped Gold Particles by Electric Fields

“…These techniques are useful tools to monitor the geometrical 4,5,10 and electrical properties 5,11 of dispersed anisotropic particles. Apart from characterization of the particle properties, electro-optical phenomena are of fundamental interest because they give insight into alignment mechanisms, 3,5,[12][13][14] double layer properties, 3,15,16,17 and long-range interactions. 13,14,18 In this paper the alignment of rod-shaped gold particles is studied by measuring the absorbance spectra of the rod dispersions as a function of the electric field strength.…”