Kinetic process of formation of discommensuration lattice in the first-order commensurate-incommensurate transition

Abstract

The stability of the discommensuration lattice (DC lattice) and the kinetic process of the first-order commensurate-incommensurate transition (C-IC transition) have been studied theoretically and experimentally. At an early stage of the C-to-IC transition, the crystal is gradually covered with the clusters of DCs. After the crystal is covered with a DC lattice, its lattice spacing narrows to the final equilibrium value. At an early stage of the IC-to-C transition, the DC lattice remains to cover the crystal and only its lattice spacing widens. After the spacing has widened to the threshold value, the commensurate phase comes to appear and finally covers the whole crystal. This peculiar feature of the phase transition arises from the nature of the order parameter of the incommensurate system.

Key Words:

• Commensurate-incommensurate transition
• discommensuration lattice
• kinetics