Imperfect Oriented Attachment:  Accretion and Defect Generation of Nanosize Rutile Condensates

Imperfect oriented attachment of nanoparticles over specific surfaces is rationalized to cause accretion and defects for the rutile condensates. Analytical electron microscopy indicates that rutile nanoparticles prepared by Nd:YAG laser ablation on Ti targets have well-developed {110} and {011} surfaces with steps. These surfaces are beneficial to {∼110} and {∼011} vicinal attachment, causing, respectively, edge dislocations and planar defects, i.e., fault and twin for rutile crystal. The {011}-interface relaxation, by shearing along 〈011〉 directions, accounts for a rather high density of edge dislocations near the planar defects thus formed. Brownian motion may proceed above a critical temperature for anchorage release at the interface of imperfect attached nanoparticles until an epitaxial relationship is reached.