Navegando por Autor "Fernandes, Fernanda de Sousa"
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Item A comprehensive topological analysis on a new bromine-chalcone with potential nonlinear optical properties(2019) Paula, Renata Layse Gonçalves de; Duarte, Vitor Santos; Fernandes, Fernanda de Sousa; Vaz, Wesley Fonseca; Ribeiro, Ítalo Nuta; Osorio, Francisco Aparecido Pinto; Valverde, Clodoaldo; Oliveira, Guilherme R.; Napolitano, Hamilton BarbosaThe application of organic crystals on nonlinear optical (NLO) materials has been increasing in recent years, and compounds like chalcones are interesting due to their significant third-order nonlinear properties. Hereof, we describe the synthesis, molecular structure, supramolecular arrangement, and theoretical calculations for a bromine-chalcone 3-(4-bromophenyl)-1-[3-(2-oxo-2-phenylethoxy)phenyl]-propenone (BC), which crystallized into noncentrosymmetric space group Pc. Also, a comprehensive topological analysis performed by QTAIM highlights the observed halogen bonds on solid state. In addition, the thermal stability was studied in temperatures smaller than 800 °C showing BC crystal as potential optical devices at temperatures up to 250 °C. Finally, the NLO properties indicate a photonic application based on strong third-order nonlinear response.Item Growth and characterization of a new chlorine substituted chalcone: a third order nonlinear optical material(2020) Ribeiro, Ítalo Nuta; Paula, Renata Layse Gonçalves de; Wenceslau, Patricia Rafaella Santana; Fernandes, Fernanda de Sousa; Duarte, Vitor Santos; Vaz, Wesley Fonseca; Oliveira, Guilherme Roberto de; Valverde, Clodoaldo; Napolitano, Hamilton Barbosa; Baseia, BasilioIn this present study, the structural, molecular, electronic, thermal studies, and the nonlinear optical (NLO) properties of a newly synthesized chalcone derivative 3-(2-chloro-phenyl)-1-[3-(2-oxo-2-phenyl-ethoxy)-phenyl]-propan-1-one (CPPO) were performed. The molecular structure of titled compound was described by single crystal X-ray diffraction, nuclear magnetic resonance spectroscopy (1H and 13C NMR) and thermal analysis (TGA-DTG analysis). The supramolecular arrangement in solid state was confirmed by Hirshfeld surface analysis and 2D-fingerprint plots. The CPPO compound was crystallized on non-centrosymmetric monoclinic space group P21 and the supermolecule approach (SM) at DFT/CAM-B3LYP/6-311++G(d,p) level was used to analyze the nonlinear optical properties in crystalline environment. The total moment of dipole, the averages of linear polarizability and first and second hyperpolarizabilities, linear refractive index and the third-order nonlinear susceptibility were calculated as function of the electric field frequency. The -value of the CPPO crystal at 532 nm is 266 times greater than the experimental result of organic crystal (2E)-1-(3-bromophenyl)-3-[4(methylsulfanyl)phenyl]prop-2-en-1-one [1], demonstrating that CPPO crystal has good potential for use as NLO material.Item Insights into chalcone analogues with potential as antioxidant additives in diesel–biodiesel blends(2022) Borges, Igor Dalarmelino; Faria, Eduardo Coelho da Mata; Custodio, Jean Marcos Ferreira; Duarte, Vitor Santos; Fernandes, Fernanda de Sousa; Alonso, Christian Gonçalves; Silva, Valter Henrique Carvalho; Oliveira, Guilherme Roberto de; Napolitano, Hamilton BarbosaBiodiesel production is one of the promising strategies to reduce diesel consumption and an important contribution to climate change. However, biodiesel stability remains a challenging problem in biofuel use in the global energy matrix. In this context, organic additives have been investigated to minimize these problems and reduce harmful emissions to comply with fuel requirement standards. In this study, we discuss a comprehensive structural description, a behavior of B15 [85% volume of diesel and 15% volume of biodiesel (B100)] stability in the presence of antioxidants (chalcone analogues), and a theoretical calculation to pave the way for clarifying and expanding the potential of title compounds as an antioxidant additive for diesel–biodiesel blends. Finally, a systematic description of the oxidation stability was undertaken using a specialized machine learning computational pySIRC platform.Item A new halogen-chalcone with potential for application in biofuels(2020) Faria, Eduardo Coelho da Mata; Duarte, Vitor Santos; Silva, Aline Magalhães da; Fernandes, Fernanda de Sousa; Oliveira, Guilherme Roberto de; Napolitano, Hamilton BarbosaFossil fuels, which represent an important villain for the terrestrial ecosystem, are non-renewable sources of energy, which prompt many discussions about how long petroleum will remain available for use. As an alternative, new energy sources have been explored, including biofuels, such as biodiesel and ethanol. However, their use can raise some problems, such as lower storage stability associated with poor oxidation stability and lower energy availability, which affect consumption, emissions, and energy efficiency. In this context, a comprehensive study with structural description, theoretical calculations, and calorific power test was performed for a new halogen chalcone 4-(4-chlorophenyl)-1-[4-(2-oxo-2-phenylethoxy)phenyl]butan-2-one to understand its supramolecular arrangement and physicochemical properties. The structural description was carried out by X-ray diffraction with the contribution of Hirshfeld surfaces. The theoretical calculations were carried out using density functional theory with the contribution of calorific power determined by a calorimetric pump. All observed results characterize the new chalcone as a potential additive for biofuels.Item Relating the crystal structure and third-order nonlinear susceptibility of a new neolignan derivative(2022) Custodio, Jean Marcos Ferreira; Fernandes, Fernanda de Sousa; Vaz, Wesley Fonseca; Oliver, Allen G.; Valverde, Clodoaldo; Osorio, Francisco Aparecido Pinto; Oliveira, Guilherme Roberto de; Fonseca, Tertius Lima daTheoretical results for electronic properties of a synthesized nitro chalcone with a neolignan moiety (NOPP) whose crystal structure was elucidated by using Single Crystal X-ray Diffraction (SCXRD) are presented. The NOPP crystal structure suggests that its potential for nonlinear applications is related to the chalcone moiety planarity and that the lamellar NOPP crystal packing along with dimer formation maximize the electronic properties. The in-crystal absorption spectrum and static and dynamic electric properties were determined by applying a supermolecule approach in combination with an iterative electrostatic scheme, in which the surrounding molecules are represented by point charges. It is found that the environment polarization effect is mild for absorption spectrum and linear polarizability, but it is marked for second hyperpolarizability of NOPP molecule. Estimates of macroscopic quantities from the results of an explicit unit cell of crystal, including environment polarization effect and partially the exchange and dispersion effects, are presented. The results illustrate the role played by these interactions on the third-order nonlinear susceptibility of the NOPP crystal, and a theoretical (λ = 532 nm) prediction of 2.81 × 10−20 (m/V)2 for χ(3)(−ω;ω,ω,ω) suggests that the NOPP crystal is a very promising NLO material.