Banca de DEFESA: RONIEL DE LIMA ARAÚJO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : RONIEL DE LIMA ARAÚJO
DATA : 17/03/2017
HORA: 15:00
LOCAL: Auditório do DFTE
TÍTULO:

Structural, electronic, optical and vibrational properties of L-Threonine crystal: Computational simulations in DFT formalism.

PALAVRAS-CHAVES:

DFT, Biophysics, Optical and Electronic properties

PÁGINAS: 67
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Física
RESUMO:

In this work, we study the structural, electronic, optical and vibrational properties of orthorhombic l-threonine crystals, obtained through computational simulations in the DFT formalism (Density Functional Theory), the local density approximations (LDA-CAPZ) and the generalized gradient (GGA-PBE). L-threonine is an essential aminoacid that plays an important role in biological systems, being the last of the 20 aminoacids that make up the proteins, to be identified. For the crystal l-threonine, the optimization of crystalline geometry, network parameters, angles and inter atomic distances, band structure, state-by-atom density, optical absorption, dielectric function, refractive index, Optical conductivity, loss function, infrared spectrum and Raman. The calculated network parameters are close to the experimental results, a band gap direct E(Γ → Γ)=5,06 eV and band gap indirect E(X→S)=4,91 eV were obtained within the GGA and LDA level, respectively. The analysis of the electron states density allowed to identify the contributions per atom for the states of the valence and conduction bands, in the optical properties it is possible to observe a sensitivity to the plane of incident light polarization 001. A good agreement was obtained between the vibrational spectra IR and Raman theoretical and experimental data of the crystal l-threonine.

MEMBROS DA BANCA:
Externo à Instituição - ANTONIO DE MACEDO FILHO - UESPI
Externo ao Programa - 2578455 - CARLOS ANTONIO BARBOZA
Externo ao Programa - 1354851 - MANOEL SILVA DE VASCONCELOS
Presidente - 1352009 - UMBERTO LAINO FULCO