AN UNEXPECTED LOW - COVERAGE c ( 2 x 2 ) PHASE
نویسنده
چکیده
We describe a latticegas model of adsorption on a square substrate in which an adsorbed p(2 X 2) phase disorders through an intermediate ~(2 x 2) phase as the coverage is lowered from l/4 of a monolayer. The occurrence of the low coverage ~(2 X 2) phase can be understood in terms of a relatively small interfacial free energy between pairs of the four types of ordered domains in the ~(2x2) phase. The diffraction features of this phase are indistinguishable from those of standard ~(2 x 2) phases.
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