Effect of polydispersity on the crystallization kinetics of suspensions of colloidal hard spheres when approaching the glass transition

@article{citeulike:2423268, abstract = {We present a comprehensive study of the solidification scenario in suspensions of colloidal hard spheres for three polydispersities between 4.8\% and 5.8\%, over a range of volume fractions from near freezing to near the glass transition. From these results, we identify four stages in the crystallization process: (i) an induction stage where large numbers of precursor structures are observed, (ii) a conversion stage as precursors are converted to close packed structures, (iii) a nucleation stage, and (iv) a ripening stage. It is found that the behavior is qualitatively different for volume fractions below or above the melting volume fraction. The main effect of increasing polydispersity is to increase the duration of the induction stage, due to the requirement for local fractionation of particles of larger or smaller than average size. Near the glass transition, the nucleation process is entirely frustrated, and the sample is locked into a compressed crystal precursor structure. Interestingly, neither polydispersity nor volume fraction significantly influences the precursor stage, suggesting that the crystal precursors are present in all solidifying samples. We speculate that these precursors are related to the dynamical heterogeneities observed in a number of dynamical studies.}, author = {Schope, H. J. and Bryant, G. and van Megen, W. }, citeulike-article-id = {2423268}, doi = {10.1063/1.2760207}, journal = {J. Chem. Phys.}, keywords = {colloids, crystals, hard-sphere, nucleation, polydisperse}, pages = {084505+}, posted-at = {2008-02-24 19:24:04}, priority = {4}, title = {Effect of polydispersity on the crystallization kinetics of suspensions of colloidal hard spheres when approaching the glass transition}, url = {http://dx.doi.org/10.1063/1.2760207}, volume = {127}, year = {2007} }

TY - JOUR ID - citeulike:2423268 L3 - citeulike-article-id:2423268 TI - Effect of polydispersity on the crystallization kinetics of suspensions of colloidal hard spheres when approaching the glass transition JF - J. Chem. Phys. VL - 127 SP - 084505 N2 - We present a comprehensive study of the solidification scenario in suspensions of colloidal hard spheres for three polydispersities between 4.8% and 5.8%, over a range of volume fractions from near freezing to near the glass transition. From these results, we identify four stages in the crystallization process: (i) an induction stage where large numbers of precursor structures are observed, (ii) a conversion stage as precursors are converted to close packed structures, (iii) a nucleation stage, and (iv) a ripening stage. It is found that the behavior is qualitatively different for volume fractions below or above the melting volume fraction. The main effect of increasing polydispersity is to increase the duration of the induction stage, due to the requirement for local fractionation of particles of larger or smaller than average size. Near the glass transition, the nucleation process is entirely frustrated, and the sample is locked into a compressed crystal precursor structure. Interestingly, neither polydispersity nor volume fraction significantly influences the precursor stage, suggesting that the crystal precursors are present in all solidifying samples. We speculate that these precursors are related to the dynamical heterogeneities observed in a number of dynamical studies. KW - colloids KW - crystals KW - hard-sphere KW - nucleation KW - polydisperse AU - Schope, HJ AU - Bryant, G AU - van Megen, W PY - 2007/// UR - http://dx.doi.org/10.1063/1.2760207 ER -