K. Yamaoka et al., ELECTROOPTICS OF DISPERSED SYSTEMS .1. REVERSING-PULSE ELECTRIC BIREFRINGENCE OF MONTMORILLONITE PARTICLES SUSPENDED IN AQUEOUS-MEDIA, Chemistry Letters, (3), 1994, pp. 563-566
Reversing-pulse electric birefringence of montmorillonite was measured
in aqueous media at 25 degrees C and at 633 nm. The counterion for th
is clay was either Na+ or Mg2+. The electric field orientation of the
disk-shaped particle was due to ion-induced dipole moments but not due
to permanent dipole moment.