Simulações moleculares: métodos e aplicações

Author(s)

Rodrigo Moura Freitas

• Document type: Master's Dissertation
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Instituto de Física Gleb Wataghin
• Defense date: 2013-07-29

Examining board members

Maurice de Koning; Alex Antonelli; João Francisco Justo Filho

• Advisor: Maurice de Koning

Abstract

Due to the conceptual and technical advances being made in computational physics and computational materials science we have been able to tackle problems that were inaccessible a few years ago. In this dissertation we study the evolution of some of these techniques, presenting the theory and simulation methods to study _rst order phase transitions with emphasis on state-of-the-art free-energy calculation (Reversible Scaling) and rare event (Forward Flux Sampling) methods using the atomistic simulation technique of Molecular Dynamics. The evolution and efficiency improvement of these techniques is presented together with applications to simple systems that allow exact solution as well as the more the complex case of Martensitic phase transitions. We also present the application of numerical methods to study Pauling\'s model of ice. We have developed and implemented a new algorithm for efficient generation of disordered ice structures. This ice generator algorithm allows us to create ice Ih cells of sizes not reported before. Using this algorithm we address finite size effects not studied before (AU)

• FAPESP's process: 10/13902-4 - Study of Martensitic Phase Transitions in Metallic Alloys
• Grantee: Rodrigo Freitas
• Support Opportunities: Scholarships in Brazil - Master