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Phase separation in binary colloids with charge asymmetry

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 نشر من قبل Paddy Royall
 تاريخ النشر 2012
  مجال البحث فيزياء
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We report that binary dispersions of like-charged colloidal particles with large charge asymmetry but similar size exhibit phase separation into crystal and fluid phases under very low salt conditions. This is unexpected because the effective colloid-colloid pair interactions are accurately described by a Yukawa model which is stable to demixing. We show that colloid-ion interactions provide an energetic driving force for phase separation, which is initiated by crystallization of one species.



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