Banca de DEFESA: RODRIGO NEVES DOS SANTOS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : RODRIGO NEVES DOS SANTOS
DATA : 28/11/2019
HORA: 15:00
LOCAL: Instituto de Física da Universidade Federal da Bahia
TÍTULO:

“Magnetic Properties of KNaMSi 4 O 10 (M = Fe, Cu, Mn) Molecular Magneto under Hydrostatic Pressure Using First Principle Calculation”,

PALAVRAS-CHAVES:

molecular magnets - density functional theory - magnetic coupling - magnetic transition.

PÁGINAS: 119
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

Molecular magnets are materials with interesting properties: high magnetization, high remanence, among others. It has applications in areas such as magnetic recording, optical magneto, magnetic cooling, information and quantum computing. In this work we investigate the structural, electronic and magnetic properties of 3 molecular magnets that have the structural formula KNaMSi4O10 (M = Fe, Cu, Mn) using the theory of the exchange rate and correlation generalized gradient approximation (GGA) in the approximation of Perdew-Burke-Ernzerhof (PBE) with the electron-ion interaction given by PAW (projector augmented wave). The net parameters of the equilibrium are close to the experimental values with errors less than or equal to 1.7%. In addition, we obtained the derivative and bulk modulus of these materials - not yet calculated or measured for the manganese and iron compounds. In addition, we conclude that the copper compound is a metal, while the other materials are semiconductor. The magnetic nature of these materials has been correctly described. The magnetic coupling value was very close to the experimental with error less than 0.1% for manganese. Other coupling values gave errors around 20%. Investigation of the magnetic transition when the system is subjected to hydrostatic pressure has shown that manganese compound does not transition to the ferromagnetic state, while iron does not transition to the application of approximately 40 GPa and copper undergoes a transition in around 8 GPa. 

MEMBROS DA BANCA:
Presidente - 1650037 - JAILTON SOUZA DE ALMEIDA
Externo à Instituição - PEDRO PAULO DE MELLO VENEZUELA - UFF
Interno - 1474625 - ROBERTO RIVELINO DE MELO MORENO