CRITICAL-BEHAVIOR AT CHIRAL MELTING - DISORDERING OF THE SI(113)-(3X1) RECONSTRUCTION

Results of an x-ray-scattering study of the (3 x 1)-to-disordered phas e transformation of the Si(113) surface are reported. A continuous com mensurate-solid to incommensurate-fluid transformation occurs at T(c) = 959 K. A new two-dimensional universality class is identified and ch aracterized. Specifically, we find that the correlation lengths in the disordered phase scale anisotropically, and that the product of the i ncommensurability and the correlation length along the incommensurate direction is constant.