Publications

2019
Dias RF, da Costa CC, Manhabosco TM, de Oliveira AB, Matos MJS, Soares JS, Batista RJC. Ab initio molecular dynamics simulation of methanol and acetonitrile: The effect of van der Waals interactions. Chemical Physics Letters [Internet]. 2019;714 :172 - 177. Publisher's VersionAbstract
We employed PBE and BLYP semi-local functionals and the van der Waals density functional of Dion et al. (2004) (vdW-DF) to investigate structural properties of liquid acetonitrile and methanol. Among those functionals the vdW-DF is the only one that correctly predicts energy minima in inter-molecular interactions between acetonitrile molecules. We found that van der Waals interactions have a negligible effect on H-bonds in methanol chains. However, it significantly increases chain packing resulting in a more dense liquid in comparison to the other two functionals. The overall trend is that the vdW-DF tends to overestimate density and bulk modulus, meanwhile the semi-local functionals tend to underestimate density. Thus, van der Waals interactions play an important role in the properties of liquids in which much stronger dipole-dipole interactions are present.
Souza FS, Matos MJS, Galvão BRL, Arapiraca AFC, da Silva SN, Pinheiro IP. Adsorption of CO2 on biphasic and amorphous calcium phosphates: An experimental and theoretical analysis. Chemical Physics Letters [Internet]. 2019;714 :143 - 148. Publisher's VersionAbstract
Calcium phosphates are suggested as a CO2 adsorbent via pressure swing adsorption. Amorphous calcium phosphate (ACP) and biphasic calcium phosphate (BCP) (composed of hydroxyapatite and beta-tricalcium phosphate) were investigated for the capture/immobilization of the gas. A fluidized bed was set up to assess the levels of CO2 adsorption by ACP and BCP. A gaseous mixture was synthesized, mimicking the conditions for possible industrial use. The results show a significant reduction in CO2 concentrations. Using DFT calculations, we show that CO2 adsorption increases the stability by reducing the surface energy. The energies involved and preferential adsorption sites were also theoretically predicted.
dos Santos PL, Silveira OJ, Huang R, Jardim GAM, Matos MJS, da Silva Júnior EN, Monkman AP, Dias FB, Cury LA. Dynamics of aggregated states resolved by gated fluorescence in films of room temperature phosphorescent emitters. Phys. Chem. Chem. Phys. [Internet]. 2019;21 :3814-3821. Publisher's VersionAbstract
Phenazine derivative molecules were studied using steady state and time resolved fluorescence techniques and demonstrated to lead to strong formation of aggregated species, identified as dimers by time dependent density functional theory calculations. Blended films in a matrix of Zeonex®, produced at different concentrations, showed different contributions of dimer and monomer emissions in a prompt time frame, e.g. less than 50 ns. In contrast, the phosphorescence (e.g. emission from the triplet state) shows no significant effect on dimer formation, although strong dependence of the phosphorescence intensity on concentration is observed, leading to phosphorescence being quenched at higher concentration.
2018
da Costa Junior E, da Fernandes BS, da Lima GS, de Siqueira AJ, Paiva JNM, e Santos MG, Tavares JP, de Souza TV, Gomes TMF. Divulgacão e ensino de Astronomia e Física por meio de abordagens informais. Revista Brasileira de Ensino de FÃ\-sica [Internet]. 2018;40. Publisher's Version
Silva Nunes ME, de Silva ÉM, Martins PHL, Plascak JA, Florencio J. Effects of a magnetic field on the dynamics of the one-dimensional Heisenberg model with Dzyaloshinskii-Moriya interactions Phys. Rev. E. PHYSICAL REVIEW E [Internet]. 2018 :null. Publisher's Version
da C. Gonçalves M, Taylor J, Rossoni Júnior J, Carolina S. Rabelo A, Costa D, Cazati T, M. R. dos Santos V. Preliminary Studies of the Cytotoxicity and Photoprotective Properties of Benzophenone and Lactone Derivatives. Revista Virtual de Química. 2018;10 :600-608.
Barboza APM, Matos MJS, Chacham H, Batista RJC, de Oliveira AB, Mazzoni MSC, Neves BRA. Compression-Induced Modification of Boron Nitride Layers: A Conductive Two-Dimensional BN Compound. ACS Nano [Internet]. 2018 :null. Publisher's Version
de Sousa TASL, Fernandes TFD, Matos MJS, Araujo END, Mazzoni MSC, Neves BRA, Plentz F. Thionine Self-Assembled Structures on Graphene: Formation, Organization, and Doping. Langmuir [Internet]. 2018;34 (23) :6903-6911. Publisher's Version
Colla T, Mohanty PS, Nöjd S, Bialik E, Riede A, Schurtenberger P, Likos CN. Self-Assembly of Ionic Microgels Driven by an Alternating Electric Field: Theory, Simulations, and Experiments. ACS Nano [Internet]. 2018 :null. Publisher's Version
Alencar TV, von Dreifus D, Moreira MGC, Eliel GSN, Yeh C-H, Chiu P-W, Pimenta MA, Malard LM, de Paula AM. Twisted bilayer graphene photoluminescence emission peaks at van Hove singularities. Journal of Physics: Condensed Matter [Internet]. 2018;30 (17) :175302. Publisher's VersionAbstract
We report on photoluminescence emission imaging by femtosecond laser excitation on twisted bilayer graphene samples. The emission images are obtained by tuning the excitation laser energies in the near infrared region. We demonstrate an increase of the photoluminescence emission at excitation energies that depends on the bilayer twist angle. The results show a peak for the light emission when the excitation is in resonance with transitions at the van Hove singularities in the electronic density of states. We measured the photoluminescence excitation peak position and width for samples with various twist angles showing resonances in the energy range of 1.2 to 1.7 eV.
Cariglia M, Galajinsky A, Gibbons GW, Horvathy PA. Cosmological aspects of the Eisenhart–Duval lift. The European Physical Journal C [Internet]. 2018;78 (4) :314. Publisher's VersionAbstract
A cosmological extension of the Eisenhart–Duval metric is constructed by incorporating a cosmic scale factor and the energy-momentum tensor into the scheme. The dynamics of the spacetime is governed by the Ermakov–Milne–Pinney equation. Killing isometries include spatial translations and rotations, Newton–Hooke boosts and translation in the null direction. Geodesic motion in Ermakov–Milne–Pinney cosmoi is analyzed. The derivation of the Ermakov–Lewis invariant, the Friedmann equations and the Dmitriev–Zel'dovich equations within the Eisenhart–Duval framework is presented.
Ferrari GA, de Oliveira AB, Silvestre I, Matos MJS, Batista RJC, Fernandes TFD, Meireles LM, Eliel GSN, Chacham H, Neves BRA, et al. Apparent Softening of Wet Graphene Membranes on a Microfluidic Platform. ACS Nano [Internet]. 2018 :null. Publisher's Version
de Cardoso AVM, da Paolinelli SC, Silveira CC, Cota AB. Secondary recrystallization characteristics of 3%Si grain-oriented electrical steel. Journal of Materials Research and Technology [Internet]. 2018. Publisher's Version
de Souza JB, de Souza J, de Castro LML, Siqueira MF, Savedra RML, Silva-Barcellos NM. “Evaluation of the losartan solubility in the biowaiver context by shake-flask method and intrinsic dissolution”. Pharmaceutical Development and Technology [Internet]. 2018;(ja) :1-32. Publisher's Version
Mól LAS, Rodrigues RGM, Stancioli RA, Rocha JCS, Costa BV. On the use of the energy probability distribution zeros in the study of phase transitions. Journal of Physics: Conference Series [Internet]. 2018;1012 (1) :012005. Publisher's VersionAbstract
This contribution is devoted to cover some technical aspects related to the use of the recently proposed energy probability distribution zeros in the study of phase transitions. This method is based on the partial knowledge of the partition function zeros and has been shown to be extremely efficient to precisely locate phase transition temperatures. It is based on an iterative method in such a way that the transition temperature can be approached at will. The iterative method will be detailed and some convergence issues that has been observed in its application to the 2D Ising model and to an artificial spin ice model will be shown, together with ways to circumvent them.
Saraiva Bispo LC, Silva Nunes ME. Método das Relações de Recorrência aplicado no problema do elétron em campo magnético constante e uniforme. Revista Brasileira de Ensino de Física [Internet]. 2018;40. Publisher's Version
Cariglia M, Giambò R, Perali A. Electronic Properties of Curved Few-Layers Graphene: A Geometrical Approach. Condensed Matter [Internet]. 2018;3 (2, ARTICLE NUMBER = 1). Publisher's VersionAbstract
We show the presence of non-relativistic Lévy-Leblond fermions in flat three- and four-layers graphene with AB stacking, extending the results obtained in Cariglia et al. 2017 for bilayer graphene. When the layer is curved we obtain a set of equations for Galilean fermions that are a variation of those of Lévy-Leblond with a well defined combination of pseudospin, and that admit Lévy-Leblond spinors as solutions in an approriate limit. The local energy of such Galilean fermions is sensitive to the intrinsic curvature of the surface. We discuss the relationship between two-dimensional pseudospin, labelling layer degrees of freedom, and the different energy bands. For Lévy-Leblond fermions, an interpretation is given in terms of massless fermions in an effective 4D spacetime, and in this case the pseudospin is related to four dimensional chirality. A non-zero energy band gap between conduction and valence electronic bands is obtained for surfaces with positive curvature.
Araujo KAS, Cury LA, Matos MJS, Fernandes TFD, Cançado LG, Neves BRA. Electro-optical interfacial effects on a graphene/π-conjugated organic semiconductor hybrid system. Beilstein Journal of Nanotechnology. 2018;9 :963-974.
de Brito ACF, Correa RS, Pinto AA, Matos MJS, Tenorio JC, Taylor JG, Cazati T. Synthesis, crystal structure, photophysical properties and theoretical studies of a novel bis(phenylisoxazolyl) benzene derivative. Journal of Molecular Structure [Internet]. 2018 :-. Publisher's VersionAbstract
Abstract Isoxazoles have well established biological activities but, have been underexplored as synthetic intermediates for applications in materials science. The aims of this work are to synthesis a novel isoxazole and analyze its structural and photophysical properties for application in electronic organic materials. The novel bis (phenylisoxazolyl) benzene compound was synthesized in four steps and characterized by NMR, high resolution mass spectrometry, differential thermal analysis, infrared spectroscopy, cyclic voltammetry, ultraviolet–visible spectroscopy, fluorescence spectroscopy, \DFT\ and \TDDFT\ calculations. The molecule presented optical absorption in the ultraviolet region (from 290 nm to 330 nm), with maximum absorption length centered at 306 nm. The molar extinction coefficients (ε), fluorescence emission spectra and quantum efficiencies in chloroform and dimethylformamide solution were determined. Cyclic voltammetry analysis was carried out for estimating the \HOMO\ energy level and these properties make it desirable material for photovoltaic device applications. Finally, the excited-state properties of present compound were calculated by time-dependent density functional theory (TDDFT).
Chacham H, Barboza APM, de Oliveira AB, de Oliveira CK, Batista RJC, Neves BRA. Universal deformation pathways and flexural hardening of nanoscale 2D-material standing folds. Nanotechnology [Internet]. 2018;29 (9) :095704. Publisher's VersionAbstract
In the present work, we use atomic force microscopy nanomanipulation of 2D-material standing folds to investigate their mechanical deformation. Using graphene, h-BN and talc nanoscale wrinkles as testbeds, universal force–strain pathways are clearly uncovered and well-accounted for by an analytical model. Such universality further enables the investigation of each fold bending stiffness κ as a function of its characteristic height h 0 . We observe a more than tenfold increase of κ as h 0 increases in the 10–100 nm range, with power-law behaviors of κ versus h 0 with exponents larger than unity for the three materials. This implies anomalous scaling of the mechanical responses of nano-objects made from these materials.

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