ECRYS - 93
J. Phys. IV France 03 (1993) C2-159-C2-162
Slightly perturbed two-dimensional solid : crystal, hexatic or glass ?R.E. KUSNER1, J.A. MANN2, J. KERINS3, WJ. BENTON3, 4 and A.J. DAHM1
1 Department of Physics, Case Western Reserve University, Cleveland, OH 44106, U.S.A.
2 Department of Chemical Engineering, Case Western Reserve University, Cleveland, OH 44106, U.S.A.
3 BP America Warrensville Research and Environmental Science Center, Warrensville Center, OH 44128, U.S.A.
4 BP Research, Sunbury Research Center, Sunbury England
Melting properties of a two-dimensional system comprised of ~ 1 µm diameter, monodispersed, polystyrene spheres are compared with those of a system containing a onepercent concentration of larger spheres which have a larger interparticle interaction. The spheres interact via a dipolar interaction which is controlled externally. The translational and bond-orientational correlation functions are examined as a function of the dipole strength. The monodispersed system exhibits two-stage melting. In the system with a one-percent concentration of larger spheres the correlation functions are characteristic of a hexatic phase at the largest interaction strengths. Dislocations are pinned to the larger particles.
© EDP Sciences 1993