  We demonstrate a novel method of introducing point defects (mono and
di-vacancies) in a confined mono-layer colloidal crystal by manipulating
individual particles with optical tweezers. Digital video microscopy is used to
study defect dynamics in real space and time. We analyze the topological
arrangements of the particles in the defect core and establish their connection
with the energetics of the system. It is found that thermal fluctuations excite
point defects into \textit{dislocation multipole} configurations. We extract
the dislocation pair potential at near field, where cores overlap and linear
elasticity is not applicable.
