Computational investigations of inhomogeneous elastic effects near phase transitions

Abstract

We present different approaches to computer simulations of the order-disorder phase transition in thiocyanate crystals. In these systems the order parameter is coupled to the strain by coupling of the type ŋ²ε. This coupling plays the dominant role in the behavior of the system below T _c. Molecular Dynamics and Monte Carlo techniques give the proper temperature dependence of the order parameter and the behavior of the fluctuations similar to that observed experimentally. The ab initio calculations allow us to render properly the structural properties of crystals like KSCN and additionally can become the basis for more realistic phenomenological models.

Key Words:

• Computational investigation
• Inhomogeneous elastic effects
• Phase transitions
• Computer simulations
• Thiocyanate crystals