Banca de DEFESA: RONIEL DE LIMA ARAÚJO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RONIEL DE LIMA ARAÚJO
DATE: 18/02/2022
TIME: 09:00
LOCAL: Plataforma Google Meet
TITLE:

Studies of the structural, electronic, optical, vibrational and thermodynamic properties of neurotransmitters and levodopa
in the DFT formalism.

KEY WORDS:

DFT, neurotransmitters,levodopa, biophysics, optical and electronic properties, thermodynamics

PAGES: 109
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

In this work, we will present a study of the structural, electronic, optical, vibrational and thermodynamic properties of the
crystals of dopamine, l-dopa, noradrenaline and adrenaline, through computer simulations in the DFT formalism (Density
Functional Theory), where the generalized gradient approximation (GGA-PBE) and the hybrid functional HSE06 were used.
From the experimental data of the four crystal structures, the optimization of the crystal geometry, calculation of the density of
states and band structure, optical absorption, dielectric function, refractive index, optical conductivity, reflectivity, loss
function, infrared and Raman spectrum and also Debye temperature, enthalpy, free energy, T*entropy and heat capacity were
performed. The new lattice parameters found showed good agreement with the experimental values. Through the functional
GGA-PBE (HSE06), we found that: dopamine presented an indirect band gap E=3.8 eV (4.70 eV), for noradrenaline we
obtained an indirect band gap E=3.48 eV (4.40 eV), for adrenaline an indirect band gap E=3.53 eV (4.60 eV) and a direct band
gap E=3.09 eV (3.60 eV) was obtained for the l-dopa crystal. The analysis of the densities of electronic states made it possible
to identify the contributions per atom to the states of the valence and conduction bands. In the optical properties,it is possible
to observe an absorption of light in the ultraviolet region, and a greater sensitivity in the absorption of polarized radiation in the
100 direction, for dopamine, noradrenaline and l-dopa, while adrenaline presents a greater absorption ofpolarized light with
the polarization direction 001. IR and Raman spectra werecalculated,and vibration modes analyzed. The thermal capacity at
room temperature found was: 210.01 cal/cell.K, 121 cal/cell.K, 182 cal/cell.K and 103 cal/cell.K, for dopamine,l-dopa,
noradrenaline and adrenaline, respectively.

BANKING MEMBERS:
Externo à Instituição - ANTONIO DE MACEDO FILHO - UESPI
Externo ao Programa - 2578455 - CARLOS ANTONIO BARBOZA
Interno - 1519258 - DORY HELIO AIRES DE LIMA ANSELMO
Interno - 345638 - EUDENILSON LINS DE ALBUQUERQUE
Interno - 6346140 - LUCIANO RODRIGUES DA SILVA
Externo à Instituição - MARCELO LEITE LYRA - UFAL
Presidente - 1352009 - UMBERTO LAINO FULCO