Structural properties and phase behavior in colloidal suspensions

Barr, Stephen A.

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https://hdl.handle.net/2142/16778 Copy

Description

Title

Structural properties and phase behavior in colloidal suspensions

Author(s)

Barr, Stephen A.

Issue Date

2010-08-20T17:57:36Z

Director of Research (if dissertation) or Advisor (if thesis)

Luijten, Erik

Doctoral Committee Chair(s)

Luijten, Erik

Committee Member(s)

• Goldbart, Paul M.
• Lewis, Jennifer A.
• Schweizer, Kenneth S.

Department of Study

Materials Science & Engineerng

Discipline

Materials Science & Engr

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• colloid
• computer simulation
• nanoparticle
• Monte Carlo
• molecular dynamics

Abstract

In this dissertation I present my research on the effective interactions of colloidal particles induced by a smaller species, as well as the structure of colloidal particles undergoing freeze casting. In this research I have used a wide variety of computational techniques in order to understand these systems. Specifically, in Chapter 2 I study nanoparticle haloing in a system of silica microspheres and highly charged polystyrene nanoparticles. Computer simulations are employed to determine the effective microsphere– microsphere potential induced by the nanoparticles. From these simulations I am also able to determine the degree of nanoparticle adsorption on the microsphere surface. In Chapter 3 I investigate the depletion interaction in a system of charged microspheres and rigid rods. The effect of both rod concentration and screening length is explored. In Chapter 4 I study the effective interactions between charged colloids in the presence of multivalent counterions. The role of colloid charge is investigated and the onset of like-charged attraction is determined and compared with theoretical predictions. In order to study this system, I extended the geometric cluster algorithm to efficiently simulate systems interacting through the Coulomb potential. In Chapter 5 computer simulations are employed to elucidate the experimentally observed crystal phases of the Q and MS-2 virus particles in solution with multivalent salt and non-adsorbing polymer. Freeze casting is studied in Chapter 6. In this process colloidal particles are pushed by an advancing ice front. I use molecular dynamics simulations to study the dynamics of the colloidal particles and the resulting structures formed. iii

Graduation Semester

2010-08

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http://hdl.handle.net/2142/16778

Copyright and License Information

Copyright 2010 Stephen A. Barr

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