Nonlinear screening and gas-liquid separation in suspensions of charged colloids.
نویسندگان
چکیده
We calculate phase diagrams of charged colloidal spheres (valency Z and radius a) in a 1:1 electrolyte from multicentered nonlinear Poisson-Boltzmann theory. Our theory takes into account charge renormalization of the colloidal interactions and volume terms due to many-body effects. For valencies as small as Z = 1 and as large as 10(4) we find a gas-liquid spinodal instability in the colloid-salt phase diagram provided Z lambdaB/a > or similar 24+/-1, where lambdaB is the Bjerrum length.
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ورودعنوان ژورنال:
- Physical review letters
دوره 97 25 شماره
صفحات -
تاریخ انتشار 2006