# IF - Instituto de Física

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O IF - Instituto de Física, da Universidade Federal de Goiás, oferece Graduação em: Bacharelado em Física; Licenciatura em Física; Física Médica; e, Engenharia Física.

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Item 14, 15-epoxygeranylgeraniol and extracts isolated from Pterodon emarginatus Vog. fruits: antitumor activity on glioblastoma cells(2012-09) Hansen, Daiane; Nakahata, Adriana Miti; Haraguchi, Mitsue; Okamoto, Oswaldo Keith; Gonçalez, Edlayne; Alonso, AntonioMostrar mais Plant-derived substances have traditionally played important roles in the treatment of human diseases, including of great significance to cancer therapy. Plants of the genus Pterodon (Fabaceae, Leguminosae), commonly known as ‘sucupira’, are disseminated throughout the central region of Brazil and have been used frequently in popular medicine. In recent years, interest in these plants has increased considerably. The biological effects of their extracts and pure metabolites have been investigated in several experimental models in vivo and in vitro. Until the present day, the antitumor effect of Pterodon plants on brain tumors is unknown. Therefore, the aim of this work was to investigate the action of P. emarginatus Vogel extracts and its fractions on glioblastoma cells. The hexane (HE), dichloromethane (DE) and ethanol (EE) extracts were obtained from seeds powder in each solvent. The diterpene 14,15-epoxygeranylgeraniol was obtained from HE fractionation. For tumorigenic assays, the extracts and fractions were added to U87MG, a human glioblastoma cells line. The cell viability assay showed that the proliferation of U87MG was inhibited by both extracts and the 14,15- epoxygeranylgeraniol. Further trials in vivo will help to confirm these results, and may contribute to generate natural compounds for the treatment of this type of cancer.Mostrar mais Item 15N NMR shifts of eumelanin building blocks in water: a combined quantum mechanics/statistical mechanics approach(2020) Oliveira, Leonardo Bruno Assis; Fonseca, Tertius Lima da; Cabral, Benedito Jose CostaMostrar mais Theoretical results for the magnetic shielding of protonated and unprotonated nitrogens of eumelanin building blocks including monomers, dimers, and tetramers in gas phase and water are presented. The magnetic property in water was determined by carrying out Monte Carlo statistical mechanics sampling combined with quantum mechanics calculations based on the gauge-including atomic orbitals approach. The results show that the environment polarization can have a marked effect on nitrogen magnetic shieldings, especially for the unprotonated nitrogens. Large contrasts of the oligomerization effect on magnetic shielding show a clear distinction between eumelanin building blocks in solution, which could be detected in nuclear magnetic resonance experiments. Calculations for a π-stacked structure defined by the dimer of a tetrameric building block indicate that unprotonated N atoms are significantly deshielded upon π stacking, whereas protonated N atoms are slightly shielded. The results stress the interest of NMR experiments for a better understanding of the eumelanin complex structure.Mostrar mais Item 1D magnetic interactions in Cu Oxovanadium Phosphates (VPO), magnetic susceptibility, DFT, and single-crystal EPR(2015) Venegas Yazigi, Diego; Spodine, Evgenia; Saldias, Marianela; Vega, Andrés; Paredes García, Verónica; Calvo, Rafael; Santana, Ricardo Costa deMostrar mais We report the crystal face indexing and molecular spatial orientation, magnetic properties, electron paramagnetic resonance (EPR) spectra, and density functional theory (DFT) calculations of two previously reported oxovanadium phosphates functionalized with CuII complexes, namely, [Cu(bipy)(VO2)(PO4)]n (1) and [{Cu(phen)}2(VO2(H2O)2)(H2PO4)2 (PO4)]n (2), where bipy = 2,2′-bipyridine and phen = 1,10-phenanthroline, obtained by a new synthetic route allowing the growth of single crystals appropriate for the EPR measurements. Compounds 1 and 2 crystallize in the triclinic group P1̅ and in the orthorhombic Pccn group, respectively, containing dinuclear copper units connected by two −O–P–O– bridges in 1 and by a single −O–P–O– bridge in 2, further connected through −O–P–O–V–O– bridges. We emphasize in our work the structural aspects related to the chemical paths that determine the magnetic properties. Magnetic susceptibility data indicate bulk antiferromagnetism for both compounds, allowing to calculate J = −43.0 cm–1 (dCu–Cu = 5.07 Å; J defined as Hex(i,j) = −J Si·Sj), considering dinuclear units for 1, and J = −1.44 cm–1 (dCu–Cu = 3.47 Å) using the molecular field approximation for 2. The single-crystal EPR study allows evaluation of the g matrices, which provide a better understanding of the electronic structure. The absence of structure of the EPR spectra arising from the dinuclear character of the compounds allows estimation of weak additional exchange couplings |J′| > 0.3 cm–1 for 1 (dCu–Cu = 5.54 Å) and a smaller value of |J′| ≥ 0.15 cm–1 for 2 (dCu–Cu = 6.59 Å). DFT calculations allow evaluating two different exchange couplings for each compound, specifically, J = −36.60 cm–1 (dCu–Cu = 5.07 Å) and J′ = 0.20 cm–1 (dCu–Cu =5.54 Å) for 1 and J = −1.10 cm–1 (dCu–Cu =3.47 Å) and J′ = 0.01 cm–1 (dCu–Cu = 6.59 Å) for 2, this last value being in the range of the uncertainties of the calculations. Thus, these values are in good agreement with those provided by magnetic and single-crystal EPR measurements.Mostrar mais Item 2D quantitative imaging of magnetic nanoparticles by an ac biosusceptometry based scanning approach and inverse problem(2021) Biasotti, Gabriel Gustavo de Albuquerque; Próspero, Andre Gonçalves; Alvarez, Marcelo Dante Tacconi; Liebl, Maik; Pinto, Leonardo Antonio; Soares, Guilherme Augusto; Bakuzis, Andris Figueiroa; Baffa Filho, Oswaldo; Wiekhorst, Frank; Miranda, José Ricardo de ArrudaMostrar mais The use of magnetic nanoparticles (MNPs) in biomedical applications requires the quantitative knowledge of their quantitative distribution within the body. AC Biosusceptometry (ACB) is a biomagnetic technique recently employed to detect MNPs in vivo by measuring the MNPs response when exposed to an alternate magnetic field. The ACB technique presents some interesting characteristics: non-invasiveness, low operational cost, high portability, and no need for magnetic shielding. ACB conventional methods until now provided only qualitative information about the MNPs’ mapping in small animals. We present a theoretical model and experimentally demonstrate the feasibility of ACB reconstructing 2D quantitative images of MNPs’ distributions. We employed an ACB single-channel scanning approach, measuring at 361 sensor positions, to reconstruct MNPs’ spatial distributions. For this, we established a discrete forward problem and solved the ACB system’s inverse problem. Thus, we were able to determine the positions and quantities of MNPs in a field of view of 5 5 1 cm3 with good precision and accuracy. The results show the ACB system’s capabilities to reconstruct the quantitative spatial distribution of MNPs with a spatial resolution better than 1 cm, and a sensitivity of 1.17 mg of MNPs fixed in gypsum. These results show the system’s potential for biomedical application of MNPs in several studies, for example, electrochemical-functionalized MNPs for cancer cell targeting, quantitative sensing, and possibly in vivo imaging.Mostrar mais 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 BarbosaMostrar mais The 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.Mostrar mais Item A first-principles study of the interaction of doxorubicin with graphene(2017) Tonel, Mariana Zancan; Martins, Mirkos Ortiz; Silva, Ivana Zanella da; Pontes, Renato Borges; Fagan, Solange BinottoMostrar mais Graphene is a single layer of graphite whose carbon atoms are arranged in a hexagonal form. On the other side, doxorubicin (DOX) is a drug widely used for the treatment of various cancer diseases. In this work, we performed calculations within the Density Functional Theory (DFT) framework in order to obtain both structural and electronic properties of the graphene interacting with DOX. The results show that, in the most stable conformation, DOX interacting with pristine graphene has a binding energy of approximately 0.5 eV. Likewise, it was also verified that no major changes in the intrinsic electronic properties of graphene. Ab Initio Molecular Dynamics (AIMD) calculations show that, even at room temperature (300 K), there is a weak interaction between graphene and DOX.Mostrar mais Item A molecular dynamics study of graphyne-based electrode and biocompatible ionic liquid for supercapacitor applications(2022) Chagas, Henrique de Araujo; Fileti, Eudes Eterno ; Oliveira, Guilherme Colherinhas deMostrar mais Atomistic molecular dynamics simulations were used to investigate the properties of electrolytes based on aqueous mixtures of the biodegradable ionic liquid [Ch][Gly] with the ionic liquid [Bmim][PF6] as electrolytes in graphyne supercapacitors. Energetic, structural, and electrostatic analyses were performed to describe de Electrical Double Layer (EDL) formed near de graphyne electrodes revealing preferential adsorption of [Bmim][PF6] additive in both, positive and negative electrodes. From the energetic analysis, we found that although the structure and formation of the EDL are governed by the complex interaction network of both van der Waals and electrostatics, its interaction with the electrode is drastically dominated by van der Waals interactions. From electrostatic results, we found a reduction in total capacitance as the concentration of [Bmim][PF6] increases but overall, we observed that cholinium-based electrolytes can perform as well as most conventional ionic liquids, but with the advantage of having a low toxicity. The comparison between graphene and graphyne supercapacitors revealed a higher capacitance for graphyne, with 2.4 μF cm−2 at 2 V, even when we compare similar values for the drop potential (which occur for different values of charge density) the higher performance of the graphyne electrode is maintained; a result that corroborates the previous findings and that indicates graphyne as a promising candidate for electrochemical energy storage systems.Mostrar mais Item A new isostructural halogenated chalcone with optical properties(2021) Ludovico, Gabriela Silva; Barros, Itallo Henrique da Silva; Sallum, Lóide Oliveira; Lima, Rosa Silva; Valverde, Clodoaldo; Camargo, Ademir João; Baseia, Basilio; Napolitano, Hamilton BarbosaMostrar mais Chalcones are organic compounds that present a number of properties. This study presents a comprehensive structural description of a new derivative of a chlorine-substituted chalcone in comparison with a bromine chalcone. Also, supermolecule and sum-over-state approach were used to describe the optical properties of these structures regarding the substitution of the bromine by the chlorine atom. In addition, the electrical properties, dipole moment, linear polarizability, and second IDRI hyperpolarizability were calculated. The linear refractive index and the third-order nonlinear macroscopic susceptibility were evaluated as a function of the applied electric field frequency. Furthermore, the quantum mechanics calculations that were implemented at the M06-2X/6-311++G(d,p) level of the theory for these isostructural chalcones indicate that the change in halogen atoms does not cause meaningful changes in their conformation. Finally, we can postulate that side-to-side and the antiparallel interactions are the interaction forces that drive the crystal growth for new isostructural chalcones. The NLO properties showed title compounds that are good candidates for use as NLO materials.Mostrar mais Item A note on quantum teleportation without the Bell-state measurement in superconducting qubits(2014) Gomes, Rafael de Morais; Cardoso, Wesley Bueno; Avelar, Ardiley Torres; Baseia, BasilioMostrar mais In this paper, we offer a simple scheme to teleport a quantum state from a superconducting qubit to another spatially separated qubit, both coupled to coplanar waveguide microwave resonator. In this scheme the Bell-state measurement is not necessary, which simplifies the experimental observation. We revisit the effective model that describes such a coupled system and present the teleportation scheme with 98.7% of fidelity and 25% of success probability. We also verify the feasibility of this protocol for the transmon qubit parameters.Mostrar mais Item A novel dihydrocoumarin under experimental and theoretical characterization(2017) Vaz, Wesley Fonseca; Custodio, Jean Marcos Ferreira; Rodrigues, Núbia Maria Nunes; Santin, Lauriane Gomes; Oliveira, S. S.; Gargano, Ricardo; Osorio, Francisco Aparecido Pinto; Aquino, Gilberto Lucio Benedito de; Camargo, Ademir João; Oliveira, M. S.; Napolitano, Hamilton BarbosaMostrar mais Coumarins are natural and synthetic active ingredients widely applied in diverse types of medicinal treatments, such as cancer, inflammation, infection, and enzyme inhibition (monoamine oxidase B). Dihydrocoumarin compounds are of great interest in organic chemistry due to their structural versatilities and, as part of our investigations concerning the structural characterization of small molecules, this work focuses on crystal structure and spectroscopic characterization of the synthesized and crystallized compound 4-(4-methoxyphenyl)-3,4-dihydro-chromen-2-one (C16H14O3). Additionally, a theoretical calculation was performed using density functional theory to analyze the sites where nucleophilic or electrophilic attack took place and to examine the molecular electrostatic potential surface. Throughout all of these calculations, both density functional theory and Car–Parrinello molecular dynamics were performed by fully optimized geometry. The spectroscopic analysis indicated the presence of aromatic carbons and hydrogen atoms, and also the carbonyl and methoxy groups that were confirmed by the crystallographic structure. The C16H14O3 compound has a non-classical intermolecular interaction of type C–H⋅⋅⋅O that drives the molecular arrangement and the crystal packing. Moreover, the main absorbent groups were characterized throughout calculated harmonic vibrational frequencies. Also, natural bond orbital analysis successfully locates the molecular orbital with π-bonding symmetry and the molecular orbital with π* antibonding symmetry. Finally, the gap between highest occupied and lowest unoccupied molecular orbitals implies in a high kinetic stability and low chemical reactivity of title molecule.Mostrar mais Item A phenomenological model for the spontaneous exchange bias effect(2020) Bufaiçal, Leandro Felix de Sousa; Coutrim, Leandro Tolentino; Bittar, Eduardo Matzenbacher; Garcia, FlávioMostrar mais In this work we propose an alternative model to explain the spontaneous exchange bias (SEB) effect observed in spin glass (SG)-like systems. As in a previously proposed model [1], it is based on the unconventional dynamics of the SG-like moments at the magnetic hysteresis cycle. However, using a reliable estimate of the amount of SG-spins that are relaxing during the cycle, the new model can correctly describe the changes in the SEB observed for measurements performed at different temperatures and different maximum applied fields.Mostrar mais Item A quantum Monte Carlo study of the structural and electronic properties of small boron clusters Bn (n = … 1, ,13)(2020) Moreira, Emanuel Melo Isaac; Brito, Braulio Gabriel Alencar; Guo, Qiang Hai; Silva, Ladir Cândido daMostrar mais Using diffusion quantum Monte Carlo, density functional theory, and Hartree–Fock methods, we investigate the structural and electronic properties of small neutral boron clusters with up to 13 atoms. We determine the lowest-lying energy structures, total ground-state energy, binding energy, dissociation energy, resonance energy, and investigate the impact of electron correlation on the stability of the clusters. The obtained results show agreement with available experimental and theoretical results. Moreover, analysis of the dissociation energy, the second difference in energy, and the resonance energy indicates that the clusters B3, B4, B8, and B10 are relatively more stable.Mostrar mais Item A quantum Monte Carlo study of the structural and electronic properties of small cationic and neutral lithium clusters(2017) Brito, Braulio Gabriel Alencar; Guo, Qiang Hai; Silva, Ladir Cândido daMostrar mais Using the fixed-node diffusion quantum Monte Carlo method, we calculate the total energy of small cationic and neutral lithium clusters. We estimate the ionization potential, atomic binding energy, dissociation energy, and the second difference in energy. We present a critical analysis of the structural and electronic properties of the clusters. The bond lengths and binding and dissociation energies obtained from the calculations are in excellent agreement with the available experimental results. A comparative analysis of the dissociation energy and the second difference in energy indicates that the cationic clusters Li+3, Li+5, and Li+7are the most stable ones. We have also studied the electron correlation effects in the lithium clusters. The cationic clusters of odd-number size are relatively more favored in terms of correlation energy than their neighbors of even-number size. In the range of cluster sizes under investigation, we find that the contribution of electron correlation to ionization potential is not larger than 28% of its total values, whereas it enhances significantly the dissociation energy of the clusters reaching up to 70% of its total values for the most stable onesMostrar mais Item A stretched exponential-based approach for the magnetic properties of spin glasses(2022) Bufaiçal, Leandro Felix de SousaMostrar mais The spin glasses show intriguing characteristic features that are not well understood yet, as for instance its aging, rejuvenation and memory effects. Here a model based on a stretched exponential decay of its magnetization is proposed, which can describe the main magnetic features of spin glasses observed in experiments as the time-decay of thermoremanent magnetization, the relaxation of zero field cooled magnetization, the ac and dc magnetization as a function of temperature and others. In principle, the here proposed model could be adapted to describe other glassy systems.Mostrar mais Item A study of the thermodynamic principles and implementations of the quantum Otto engine(Universidade Federal de Goiás, 2023-08-11) Costa, Rafael do Lago Souza; Céleri, Lucas Chibebe; Céleri, Lucas Chibebe; Pontes, Renato Borges; Carvalho, Vanuildo Silva deMostrar mais This monography provides a comprehensive overview of classical and quantum thermodynamics. The classical formulations of thermodynamics are discussed in detail, including concepts such as energy and equilibrium, ideal gases and internal energy. Study the first and second laws of thermodynamics and their applications to mechanical work, heat engines and thermodynamic cycles. The present work also covers some quantum thermodynamics principles, including the use of density operators to describe pure and mixed states of quantum systems and the time evolution of these operators. The first law of quantum thermodynamics is introduced, along with the concepts of quantum adiabatic evolution and quantum Otto cycles. In addition, this monography briefly discusses the concept of Maxwell’s demon in the context of quantum thermodynamics and its implications for the second law. Overall, this work provides a comprehensive introduction to the basic principles of classical and quantum thermodynamics.Mostrar mais Item A systematic study of the optical properties of mononuclear hybrid organo–inorganic lanthanoid complexes(2020) Zapata Lizama, Matías Ignacio; Hermosilla Ibáñez, Patricio; Venegas Yazigi, Diego; Minguez Espallargas, Guillermo; Maia, Lauro June Queiroz; Gasparotto, Gisane; Santana, Ricardo Costa de; Mancisidor, Walter Alberto CañónMostrar mais A series of hybrid organo–inorganic mononuclear lanthanoid complexes, [n-NBu4]3[LnH(PW11O39)(phen)2]·H2O, denoted as LM4-1-Ln (Ln = DyIII, TbIII, EuIII, NdIII, ErIII, HoIII and GdIII), were synthesized via hydrothermal synthesis and were structurally characterized by X-ray diffraction. The optical properties of all complexes have been investigated in the solid state. The temperature-dependent emission spectra of LM4-1-Dy, LM4-1-Tb and LM4-1-Eu complexes show intense lanthanoid emissions in the visible region, while LM4-1-Nd shows near-infrared (NIR) luminescence. The EuIII complex shows typical strong red emissions from the 5D0 → 7F0,1,2,3,4 transitions, with the CIE colour coordinates (0.631,0.364), the colour purity value of 83.9% and a quantum yield of up to 4.3%, suggesting that the organic fragment has an effect on the optical properties compared to fully inorganic systems, making this complex very attractive as a red component of light-emitting diodes. The luminescence decays of LM4-1-Dy, LM4-1-Tb and LM4-1-Eu exhibit a biexponential behaviour, with τAV = 4.1(7) μs, 0.35(2) ms and 0.94(3) ms, respectively. The values obtained for Judd–Ofelt intensity parameters Ω2 and Ω4 support the interaction between the EuIII and the ligands. Furthermore, those with ErIII and HoIII present weak emissions in the visible region. The T-dependent photoluminescence results show that the LM4-1-Dy, LM4-1-Tb and LM4-1-Nd complexes have good temperature sensitivity, demonstrating that the materials have the potential to be used as a sensing element for luminescent thermometers in different temperature ranges.Mostrar mais Item A temperature dependent ZGB-like model: entropic sampling simulations(2022) Santos, E. D.; Ferreira, Lucas de Souza; Jorge, Lucas Nunes; Leão, Salviano de Araujo; Caparica, Álvaro de AlmeidaMostrar mais By means of entropic sampling simulations we study a ZGB-like model. We consider an attractive nearest-neighbor CO–CO interaction when adsorbed on the system. We also take into account an attraction between oxygen atoms, but of lesser intensity. In analyzing the effect of the temperature increase in our catalytic system, we extract the temperature at which the output of CO is very large, which we call the critical desorption temperature. This output is abrupt, and our results lead to the conclusion that this transition from a CO poisoned state to a state in which the lattice sites are occupied by oxygen atoms, vacancies, and a few CO units, is a first order phase transition. A finite-size scaling analysis was performed to extract the critical desorption temperature for an infinite system.Mostrar mais Item A utilização de esportes no ensino de física: análise de artigos publicados nos últimos 22 anos(Universidade Federal de Goiás, 2023-08-30) Lima, Vitória Ribeiro de Sousa; Ferrari, Paulo Celso; Ferrari, Paulo Celso; Cunha, Jefferson Adriany Ribeiro da; Santos, Aliny TinocoMostrar mais Despite the undeniable importance of sports in quality of life, there are access difficulties in this field, especially for people in lower classes of society, and when comes to mind the educational field, is almost completely limited to physical education classes. On the other hand, physics teachers face difficulties while teaching the regular discipline at the same time that motivates students by putting the physics in context, even though the subject is considered hard and useless. Thus, this work describes a literature review research that seeks to understand how researchers combined the two areas: physics and sports. For that, 13 papers published in the last 22 years and available on Google Scholar were selected, resulting in three categories to analyze the papers: the writer’s reasons, objectives and methods, and the ways in which the chosen sports were used to put the physics in context. We see, then, how much concerned the scientists were when approaching the physics concepts to the student’s daily life as a way to attract them to the subject. Also, the more popular sports in the papers were soccer, running, swimming and long jump, that were mainly used in the teaching of kinematics and dynamics. It is possible to conclude through the analysis that the sports helps the physics teachers, as it puts the subject in context and makes the classes more innovative, even in schools with poor structure, what can put students away from physical activities.Mostrar mais Item A6H polypeptide membranes: molecular dynamics simulation, GIAO-DFT-NMR and TD-DFT spectroscopy analysis(2020) Andrade, Douglas Xavier de; Oliveira, Guilherme Colherinhas deMostrar mais In this work, Molecular Dynamics simulation (MD), GIAO-DFT-NMR, and TD-DFT results are obtained to study structural, energetic, dynamics, and spectroscopy properties of polypeptide membranes composed of 6 alanine residue (A6) attached to one histidine residue (H). The histidine residue is simulated with a hydrogen atom bonded in different positions on the aromatic ring: at the epsilon (HSE), or delta (HSD) nitrogen. The results are presented for the A6H(SE or SD) peptide in monomer and membrane configurations to contrast the effects of an organized structure on the peptides' properties studied. Spectroscopy properties are acquired using DFT quantum mechanics calculations combined with MD classical configurations. From 25,000 MD configuration, 100 of them were selected for the calculation of spectroscopic properties. For the A6HSE and A6HSD membranes, in every 100 MD-configurations, we selected just one peptide in the center of the simulation box for quantum mechanics calculation, the other peptides, and water molecules, were considered as charge points. Our results indicate how the absorption spectrum spectroscopy and magnetic shielding constant signature of the A6H(SE or SD) polypeptides are affected when the structure goes from a free monomer in-water solution to a monomer inside a membrane structure in-water solution. The NMR results, acquired at an atomic and molecular level via theoretical studies, reproduce the performance experimentally observed, indicating the reliability of our data. This way, endorsing the methodology used to verify the spectroscopic properties of membranes from a unit monomer.Mostrar mais Item Ab initio dynamics of graphene and graphyne electrodes in vacuum and in the presence of electrolytes(2023) Fileti, Thaciana Valentina Malaspina; Oliveira, Guilherme Colherinhas de; Weitzner, Stephen E.; Wood, Brandon C.; Fileti, Eudes EternoMostrar mais Graphene and graphyne electrodes are both relevant for electrochemical energy storage applications due to their unique physical, chemical, and electronic properties. Graphyne has been considered even more attractive than graphene due to its larger specific surface area, greater electronic mobility, and intrinsic band gap. The analyses presented here reveal relevant features of graphyne in an interaction with an electrolyte that can be useful for practical applications. Although there is already a considerable volume of work on graphyne, the analysis of its properties taking into account the dynamics of its network and the interaction with the condensed medium has not yet been presented. In this work, ab initio molecular dynamics simulations were performed to study the energetic, structural, spectroscopic, and electronic properties of graphene and graphyne electrodes in vacuum and in the presence of an electrolyte (EMIM-BF4). A detailed analysis of the electrode–electrolyte interaction is reported for both systems. Structural features are presented in terms of both radial and spatial distribution functions and angular orientation distributions. Power spectral analyses and molecular orbital maps provided important insights into the intermolecular interactions in graphene and graphyne systems, describing the main differences as well as revealing similarities between them.Mostrar mais