Crystallization in quasi-two-dimensional colloidal systems at an air-water interface.

The crystallization of colloidal particles at an air-water interface is investigated by computer simulations. We numerically clarify the bond-orientational order parameter Phi(6) with different particle concentrations. In addition, the profiles of the pair-correlation function g(r), the orientational correlation function g(B)(r), and the static structure factor S(q) of this system are calculated. We find the two-stage melting of the colloidal crystal and the existence of the hexatic phase at intermediate concentration.