Academic literature on the topic 'Density Functional Theory - DFT/B3LYP'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Density Functional Theory - DFT/B3LYP.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Density Functional Theory - DFT/B3LYP"

1

Adole, Vishnu A., Tejendra R. Rajput, and Bapu S. Jagdale. "Synthesis, Molecular Structure, HOMO-LUMO, Chemical, Spectroscopic (UV-Vis and IR), Thermochemical Study of Ethyl 6-amino-5-cyano-2-methyl-4-(4-nitrophenyl)-4H-pyran-3-carboxylate: A DFT Exploration." Material Science Research India 18, no. 2 (August 30, 2021): 179–89. http://dx.doi.org/10.13005/msri/180206.

Full text
Abstract:
The ethyl 6-amino-5-cyano-2-methyl-4-(4-nitrophenyl)-4H-pyran-3-carboxylate (ACNPPC) was synthesized using an environmentally friendly method and looked into in terms ofstructural, UV-visible, vibrational, and computational analysis. In the gaseous phase, calculations of the density functional theory (DFT) with B3LYP/6-311G(d,p) level were performed. Using Time-dependent density functional theory (TD-DFT) with the B3LYP/6-311G(d,p) basis set method, the HOMO and LUMO energies are calculated. For assessing electrophilic and nucleophilic reactive sites, the molecular electrostatic surface potential (MESP) and contour plot were plotted over the optimized structure. Using computed and experimental vibrational spectra, vibrational assignments were elucidated. To illustrate the charge density in the title compound, Mulliken atomic charges are disclosed. In addition, using vibrational analysis, some thermochemical functions have also been derived. Theoretical simulations have shown the best relationship with experimental results obtained with the B3LYP/6-311G(d,p) level of theory at the DFT and TD-DFT methods.
APA, Harvard, Vancouver, ISO, and other styles
2

Pandey, Anoop Kumar, Shamoon Ahmad Siddiqui, Apoorva Dwivedi, Kanwal Raj, and Neeraj Misra. "Density functional theory study on the molecular structure of loganin." Spectroscopy 25, no. 6 (2011): 287–302. http://dx.doi.org/10.1155/2011/361849.

Full text
Abstract:
The computational Quantum Chemistry (QC) has been used for different types of problems, for example: structural biology, surface phenomena and liquid phase. In this paper we have employed the density functional method for the study of molecular structure of loganin. The equilibrium geometry, harmonic vibrational frequencies and infrared intensities were calculated by B3LYP/6-311G (d, p) method and basis set combinations. It was found that the optimized parameters obtained by the DFT/B3LYP method are very near to the experimental ones. A detailed conformational analysis was carried out. A detailed interpretation of the infrared spectra of loganin is also reported in the present work. The FT-IR spectra of loganin were recorded in solid phase. The thermodynamic calculations related to the title compound were also performed at B3LYP/6-311G (d, p) level of theory.
APA, Harvard, Vancouver, ISO, and other styles
3

Shahangi, Fereshte, Alireza Najafi Chermahini, Hossein Farrokhpour, and Abbas Teimouri. "Selective complexation of alkaline earth metal ions with nanotubular cyclopeptides: DFT theoretical study." RSC Advances 5, no. 3 (2015): 2305–17. http://dx.doi.org/10.1039/c4ra08302d.

Full text
Abstract:
The interaction of alkaline earth metal cations including Be2+, Mg2+, Ca2+, Sr2+ and Ba2+ with cyclic peptides containing 3 or 4 (S) alanine molecules (CyAla3 and CyAla4) was investigated by density functional theory (DFT-CAM-B3LYP and DFT-B3LYP).
APA, Harvard, Vancouver, ISO, and other styles
4

Sarojini, K., H. Krishnan, Charles C. Kanagam, and S. Muthu. "Molecular Structure, Vibrational Spectroscopy and Homo, Lumo Studies of 4-methyl-N-(2-methylphenyl) Benzene Sulfonamide Using DFT Method." Advanced Materials Research 665 (February 2013): 101–11. http://dx.doi.org/10.4028/www.scientific.net/amr.665.101.

Full text
Abstract:
The sulfonamide compound, 4-methyl-N-(2-methylphenyl) benzene sulfonamide has been synthesized and characterized by FTIR, NMR, UV-Vis, single crystal X-ray diffraction and thermal analysis. Density functional (DFT) calculations have been carried out for the title compound by performing DFT level of theory using B3LYP/6-31G (d,p) basis set. The calculated results show that the predicted geometry can well reproduce the structural parameters. Predicted vibrational frequencies have been assigned and compared with the experimental IR spectra and they support each other. In addition, atomic charges, frontier molecular orbitals and molecular electrostatic potential were carried out by using density functional theory (DFT/B3LYP) 6-31G (d, p) basis set. The calculated Homo and Lumo energies show that charge transfer occur in the molecule.
APA, Harvard, Vancouver, ISO, and other styles
5

Brahim, Sefia, Houari Brahim, Stéphane Humbel, and Ali Rahmouni. "Computational studies of Ni(II) photosensitizers complexes containing 1,1′-bis(diphenylphosphino)ferrocene and dithio ligands." Canadian Journal of Chemistry 98, no. 4 (April 2020): 194–203. http://dx.doi.org/10.1139/cjc-2019-0168.

Full text
Abstract:
Detailed theoretical studies of Ni(II) complexes in a distorted square planar form and containing dithio and (P, P) chelating ligands were performed. These Ni(II) complexes are investigated for their use in dye-sensitized solar cells (DSSC). Structures and UV–vis spectra are calculated at density functional theory (DFT) and time-dependent density functional theory (TD-DFT) theories using B3LYP and CAM-B3LYP functionals and 6-31G(d,p) and 6-31G+(d) basis sets. Geometry optimizations result in excellent agreement with the experimental results. Moreover, the analysis of the frontier molecular orbitals (FMOs) allowed a detailed assignment and a clear analysis of the electronic transitions. The TD-DFT calculations reproduce the main spectroscopic properties observed and substituent effects. The results reveal that all absorption spectra are characterized by mixed character mainly dominated by metal to ligand and ligand to ligand charge transfers (MLCT and LLCT). We unveil how the substituent variations affect the DSSCs features of the complexes.
APA, Harvard, Vancouver, ISO, and other styles
6

ZHANG, ZHI-HUI, TAO GAO, XIAO-FENG TIAN, and NA HE. "THERMOCHEMICAL PROPERTIES OF THE THIOCARBONYLTHIO COMPOUNDS FROM CONVENTIONAL DENSITY FUNCTIONAL THEORY CALCULATIONS." Journal of Theoretical and Computational Chemistry 09, supp01 (January 2010): 201–17. http://dx.doi.org/10.1142/s0219633610005542.

Full text
Abstract:
Density functional theory (DFT) calculations employed at two levels, B3LYP/6-31G+(d) and B3P86/6-31G+(d), are reported for the geometry, enthalpy, and free energy of reaction of a number of dithiobenzoate reversible addition fragmentation transfer (RAFT) reagents ( S=C(Ph)S–R , S=C(Z)S–CH2Ph ). Based on these theoretical data, the effectiveness of these RAFT reagents is analyzed. The conclusions, especially obtained at B3LYP/6-31G+(d) level, are in good agreement with the experimental results. Our calculations suggest that the dithiobenzoate ( S=C(Z)S–CH2Ph ), where Z is OC6H5 or N(alkyl)2 , is a poor RAFT reagent. Contrarily, the compound S=C(Ph)S–R , where R is C(Me)2Ph or C(Me)2CN , is a highly efficient RAFT reagent. Our results reveal the utility of the theoretical calculations of physical magnitudes for the rationalization of judging the effectiveness of RAFT reagents and demonstrated that DFT is a good method to calculate these data. In addition, our results on the enthalpies and Gibbs free energies of formation for the R radicals are calculated with the same method. These data are important for the design of logical and economical chemical process. Finally, the B3LYP hybrid functional is employed to predict the values of thermodynamic magnitudes for several new ithiobenzoates. Those results need to be verified by future experimental measurements or theoretical calculations.
APA, Harvard, Vancouver, ISO, and other styles
7

Turan, Haydar Taylan, Oğuzhan Kucur, Birce Kahraman, Seyhan Salman, and Viktorya Aviyente. "Design of donor–acceptor copolymers for organic photovoltaic materials: a computational study." Physical Chemistry Chemical Physics 20, no. 5 (2018): 3581–91. http://dx.doi.org/10.1039/c7cp08176f.

Full text
Abstract:
80 different push–pull type organic chromophores which possess Donor–Acceptor (D–A) and Donor–Thiophene–Donor–Thiophene (D–T–A–T) structures have been systematically investigated by means of density functional theory (DFT) and time-dependent DFT (TD-DFT) at the B3LYP/6-311G* level.
APA, Harvard, Vancouver, ISO, and other styles
8

Ghasemi, Ashraf Sadat, Mahsan Deilam, and Fereydoun Ashrafi. "INVESTIGATION OF MOLECULAR STRUCTURE AND EXPERIMENTAL AND THEORETICAL SPECTROSCOPIC STUDIES OF ANTICANCER DRUGS - A REVIEW." Ciência e Natura 38, no. 2 (May 31, 2016): 1124. http://dx.doi.org/10.5902/2179460x21525.

Full text
Abstract:
In many literatures, both experimental and computational study on molecular structure and spectroscopic assignments of anticancer drugs has been reported. The molecular geometry was obtained from the X-ray structure determination exprimentally and optimized using computational chemistry methods like Density Functional Theory (DFT) method. In this review, we have investigated calculations based on density functional theory at the B3LYP/6-31G(d,p) and B3LYP/6-311++G(d,p) levels of theory. From the optimized geometry of the molecules, Molecular structure (bond lengths, bond angles and torsion angles) and vibrational assignments have been obtained.
APA, Harvard, Vancouver, ISO, and other styles
9

Nachtigallová, Dana, Markéta Davidová, and Petr Nachtigall. "Reliability of DFT Methods for Description of Cu Sites and Their Interaction with NO in Zeolites." Collection of Czechoslovak Chemical Communications 63, no. 8 (1998): 1202–12. http://dx.doi.org/10.1135/cccc19981202.

Full text
Abstract:
The reliability of various DFT functionals for description of Cu sites and their interaction with NO in zeolites is tested. The dissociation energies of Cun+H2O and Cun+NO systems calculated with various DFT functionals are compared with those obtained at the MP2 and CCSD(T) levels of theory. It is concluded that hybrid density functional (B3LYP) gives reliable description of studied systems, while LDA seriously overestimates dissociation energies.
APA, Harvard, Vancouver, ISO, and other styles
10

A. Kadir, Laode. "Struktur dan Vibrasi Carbamida: Eksperimen dan Kajian Teoritik Density functional theory (DFT)." SAINTIFIK 6, no. 2 (August 10, 2020): 116–20. http://dx.doi.org/10.31605/saintifik.v6i2.266.

Full text
Abstract:
Pada penelitian analisis spektrum vibrasi dilakukan menggunakan spektroskopi infra merah pada rentang 500-4000 cm-1 untuk molekul karbamida. Struktur molekul, frekuensi vibrasi dasar dan intensitas dan intensitas pita vibrasi diinterpretasikan dengan bantuan optimasi struktur dan perhitungan medan gaya koordinat normal berdasarkan metode density functional theory (DFT). Penugasan getaran yang lengkap dari bilangan gelombang dibuat pada dasar distribusi energi potensial. Hasil B3LYP/6-31G skala memperlihatkan kesesuaian dengan nilai ekperimen.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Density Functional Theory - DFT/B3LYP"

1

Alhabradi, Thuraya Faleh. "DFT Study of the Covalent Functionalization of Double Nitrogen Doped Graphene." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2018. http://digitalcommons.auctr.edu/cauetds/120.

Full text
Abstract:
Covalent functionalization significantly enhances the utility of carbon nanomaterials for many applications. In this study, we investigated the functionalization of double nitrogen doped graphene by the addition of different alkyl and phenyl functional groups at N atoms in syn and anti-configurations. Density functional theory calculations at the B3LYP/def-SV(P) level were employed to understand the syn versus anti preference on functionalization. The bond lengths, bond angles, relative energies, deformation energies and HOMO-LUMO energy gaps, of the syn and anti-configurations of the functionalized 2N-doped graphenes, have been compared. Functionalization with two groups leads to considerable deformation of 2N-doped graphene, which is confirmed by the change in C–N bond lengths by attachment of the functional groups. The attachment of larger functional groups deforms 2N-doped graphene to a greater extent than smaller functional groups. The HOMO-LUMO energy gap values are the least for the alkyl functionalized products, indicating that these structures are kinetically less stable than the phenyl functionalized products.
APA, Harvard, Vancouver, ISO, and other styles
2

Schultz, Spencer Albert. "An Investigation into the Use of Density Functional Theory (DFT) Calculations for Predicting Vibrational Transitions for Perfluroinated Sulfonic Acid (PFSA) Ionomer Membranes." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/87470.

Full text
Abstract:
Perfluorinated sulfonic acid (PFSA) ionomer membranes demonstrate great potential for use in proton exchange membrane fuel cells (PEMFCs) due to their favorable electronic properties and excellent efficiency. However, the assignment of key vibrational transitions such as the symmetric sulfonate and ether stretches is not yet fully understood depriving researchers of a quick and simple technique for analyzing morphological changes. The symmetric sulfonate stretch could be used to track changes in the ionic clusters formed within the membrane while the ether stretch will provide insight into the largely semi-crystalline PTFE phase. Alterations in either regime will affect both ion transport and mechanical properties and produce a major shift in device performance. This study focused on predicting the vibrational transitions for Aquivion, 3M PFSA, and Nafion using density functional theory (DFT) with the bulk being performed using the same functional and basis set combination, B3LPY/6-31+G*. For all three ionomers, the predicted vibrational transitions were affected by changes in both the conformer and solvation method with water being used as the solvent. Despite the noted changes, both vibrational transitions were determined to be within the range of 970-1100 cm-1 with the symmetric sulfonate stretch present at around 970-1010 cm-1 and the ether stretch observed at around 1050-1100 cm-1 with solvation present. While the calculated peak positions mirror those found in the experimental spectra within the literature, the traditional normal mode assignments do not match those predicted by our calculations. However, recent studies have hypothesized that these vibrational transitions are coupled, which could explain why they have been so difficult to assign.
Master of Science
Perfluorinated sulfonic acid (PFSA) ionomer membranes show great promise for use in proton exchange membrane fuel cells (PEMFCs) due to their excellent efficiency. However, the current techniques used to determine changes in structural configurations require sophisticated equipment and trained personnel to operate. Simpler techniques exist wherein the vibrations of certain bonds can be measured upon exposure of the sample to measured amounts of infrared light. The problem with this technique is that researchers currently do not fully understand at what wavelengths certain portions of the polymer known as functional groups will vibrate. These vibrations are also known as vibrational transitions. This study was undertaken to predict through numerical solutions to the Schrödinger equation at what wavelengths two particular vibrational transitions would occur for three common ionomers, Aquivion, 3M PFSA, and Nafion. For all three structures, the positions of these transitions mirrored that observed within the literature although the functional groups assigned to these positions did not match with those identified by our calculations. However, recent studies have indicated that these vibrational transitions occur at the same positions, which could explain why they have been so difficult to assign.
APA, Harvard, Vancouver, ISO, and other styles
3

Ribeiro, Renan Augusto Pontes. "INVESTIGAÇÃO TEÓRICA DE MATERIAIS COM ESTRUTURA ILMENITA." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/2038.

Full text
Abstract:
Made available in DSpace on 2017-07-24T19:37:53Z (GMT). No. of bitstreams: 1 Renan Augusto Ribeiro.pdf: 3827899 bytes, checksum: 9440ed4880cbb0fbf9997c789341ea92 (MD5) Previous issue date: 2015-03-12
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The development of spintronic has motivated the research for new half-metallic magnetic materials due to multifunctionality of these compounds and the spin-based devices fabrication with increased performance as compared to the usual electronic devices. From this perspective, we propose a theoretical investigation of FeBO3 (B = Ti, Zr, Hf, Si, Ge, Sn) ilmenite materials based on Density Functional Theory (DFT) within B3LYP hybrid functional to investigate the B-site cation replacement effect on the structural, elastic, magnetic and electronic properties of ilmenite materials. Calculated structural parameters are in agreement with experimental results and shown that the unit cell volume can be controlled by ionic radius of the B-site metals. The bond distances for FeO6 and BO6 octahedral clarify the Jahn-Teller distortion and Fe-O-B-O-Fe intermetallic connection. The elastic behavior was investigated from bulk modulus and showed that such results were influenced by different material densities. Furthermore, these quantities can be used for analyzing the thermodynamic stability of solids, proving that FeSnO3 and FeHfO3 are unstable due to the negative values for bulk modulus. The B-site radius effect is also evidenced on the magnetic property, where Fe(Ti, Si, Ge)O3 are antiferromagnetic, while Fe(Zr, Hf, Sn)O3 are ferromagnetic. The Mulliken population analysis and charge density maps show the charge corridor formation in the [001] direction due to the intermetallic connection with the B-site metals and electronegativity affecting the stability of ilmenite materials. The Density of States and Band Structure profiles show that antiferromagnetics materials and FeZrO3 are convectional semiconductors, whereas FeHfO3 and FeSnO3 exhibit intrinsic half-metallic behavior, making them promising candidates for spintronic devices.
O desenvolvimento da spintrônica tem motivado a busca por novos materiais magnéticos com comportamento meio-metálico devido à multifuncionalidade desses compostos e ao desenvolvimento de dispositivos baseados no spin do elétron, proporcionando um aumento do desempenho em relação aos dispositivos eletrônicos usuais. Nesse trabalho, propomos a investigação teórica, baseada na Teoria do Funcional de Densidade utilizando o funcional híbrido B3LYP, dos materiais FeBO3 (B = Ti, Zr, Hf, Si, Ge, Sn) na estrutura ilmenita com objetivo de esclarecer o efeito da substituição do cátion B sobre as propriedades estruturais, elásticas, magnéticas e eletrônicas. Os parâmetros estruturais calculados se mostraram em concordância com resultados experimentais e teóricos, revelando que o volume da célula unitária é controlado pelo raio iônico do cátion B. As distâncias de ligação calculadas para os octaedros FeO6 e BO6 indicam a existência do efeito de distorção Jahn-Teller e da conexão intermetálica Fe-O-B-O-Fe. O comportamento elástico foi investigado a partir do bulk modulus, indicando que tal entidade é dependente da densidade dos materiais e discute-se a possibilidade de utilizar esse fator para análise da estabilidade termodinâmica de sólidos, sugerindo a instabilidade dos materiais FeSnO3 e FeHfO3 devido aos valores negativos de bulk modulus. O efeito do tamanho dos cátions B é evidenciado sobre as propriedades magnéticas dos materiais, sendo que Fe(Ti, Si, Ge)O3 são antiferromagnéticos; enquanto que, Fe(Zr, Hf, Sn)O3 são ferromagnéticos. A análise populacional de Mulliken e os mapas de densidade de carga mostraram a formação de um corredor de carga nas conexões intermetálicas observadas na direção [001] e que a eletronegatividade dos cátions B afeta a estabilidade dos materiais com estrutura ilmenita. Os perfis de Densidade de Estados e Estrutura de Bandas mostram que os materiais antiferromagnéticos e o FeZrO3 são semicondutores convencionais, entretanto, FeHfO3 e FeSnO3 exibem comportamento meiometálico intrínseco, tornando-os promissores candidatos para dispositivos spintrônicos, porém, com outra estrutura.
APA, Harvard, Vancouver, ISO, and other styles
4

Viana, Marco Antonio de Abreu. "Ligações de hidrogênio usuais e não usuais: um estudo comparativo das propriedades moleculares e topológicas da densidade eletrônica em HCCH --- HX e HCN --- HX com X = F, CI, CN e CCH." Universidade Federal da Paraí­ba, 2013. http://tede.biblioteca.ufpb.br:8080/handle/tede/7117.

Full text
Abstract:
Made available in DSpace on 2015-05-14T13:21:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4538639 bytes, checksum: 981ce0eef0681003af97d1a8046c66ee (MD5) Previous issue date: 2013-08-06
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The aim of this work was to study two kinds of intermolecular hydrogen bonding, the non-usual that is represented by the interaction between acetylene and the HX species (C2H2 --- HX) and the usual that is represented by the interaction between hydrogen cyanide and HX species, with X = F, Cl, CN, and HCCH. This interaction promotes changes in the structural, electronic and vibrational properties of the species involved. In this work, we employe d not onlycomputational-quantum methods MP2/6-311 + + G (d, p) and DFT/B3LYP/6-311 + + G (d, p) in order to study the structural, electronic and vibrational properties of those two types of intermolecular hydrogen bonding, but also we employed QTAIM and NBO methods to complement our research. The results have shown no significant differences between the two correlated methods employed for both types of hydrogen bonded complexes, leading us to suggest the use of the DFT/B3LYP method for studies of similar systems to those studied here, due to the lower computational demand. The increase in bond length of the HX species are enhanced due to formation of more linear complexes than T-complexes, in both calculation levels. The intermolecular bond length values in the complex HCN --- HX are smaller than in the complexes HCCH --- HX, and the values from MP2 and DFT/B3LYP are very close in each individual type of hydrogen complex, suggesting that the linear complexes are more stabilized by the formation of hydrogen bonding than the T-complexes, which can be proved by the values of the binding energy of hydrogen in HCN --- HX. Concerning the redshift effect in the harmonic vibrational mode of species HX, due to the formation of intermolecular bond, the values obtained for linear complexes hydrogen are higher than for the corresponding T-complexes, considering both calculation levels. Values were evaluated from the increase in the intensity values of the stretch mode HX bond formation due to intermolecular and, according to the model CCFOM, the term load flow is responsible for the effect on the increase of HX intensity. We also highlight the new vibrational modes, emphasizing the stretch mode of the intermolecular bond. From studies employing QTAIM, it was possible to obtain the values of electron density and the Laplacian electron density and evaluate these parameters in critical points in HX and intermolecular hydrogen bonding, thus confirming the formation of hydrogen bonded complexes. We evaluated the energy difference between π orbitals and lone pair of nitrogen (in HCN), for the species receiving proton and sigma antibonding for the hydrogen of HX, using the method of natural bond orbital variation.
O objeto de estudo deste trabalho foi a ligação de hidrogênio intermolecular de dois tipos, a não-usual representada pela interação entre o acetileno e espécies HX (C2H2---HX) e a usual representada pela interação entre o ácido cianídrico e espécies HX, com X=F, Cl, CN e HCCH. Esta interação provoca mudanças nas propriedades estruturais, eletrônicas e vibracionais das espécies envolvidas. Neste trabalho empregamos os métodos quântico-computacionais MP2/6-311++G(d,p) e DFT/B3LYP/6-311++G(d,p) para estudar as propriedades estruturais, eletrônicas e vibracionais dos dois tipos de ligação de hidrogênio intermolecular, além de complementar nossa investigação empregando os métodos QTAIM e NBO. Os resultados não mostraram diferenças significativas entre os dois métodos correlacionados empregados para ambos os tipos de complexos de hidrogênio, nos levando a sugerir o emprego do método DFT/B3LYP para estudos de sistemas semelhantes aos aqui estudados, devido a menor demanda computacional. Os valores de incremento no comprimento de ligação das espécies HX são mais acentuados devido à formação dos complexos lineares do que dos complexos-T, em ambos os níveis de cálculo. Os valores de comprimento de ligação intermolecular nos complexos HCN---HX são menores do que nos complexos HCCH---HX, sendo os valores MP2 e DFT/B3LYP bem próximos em cada tipo individual de complexo de hidrogênio, sugerindo que os complexos lineares são mais estabilizados pela formação da ligação de hidrogênio do que os complexos-T, fato que pode ser comprovado pelos valores da energia de ligação de hidrogênio em HCN---HX. Com respeito ao efeito redshift no modo vibracional harmônico das espécies HX, devido à formação da ligação intermolecular, os valores obtidos para os complexos de hidrogênio lineares são maiores do que para os correspondentes complexos-T, considerando ambos os níveis de cálculo. Foram avaliados os valores do incremento nos valores de intensidade do modo de estiramento de HX devido à formação da ligação intermolecular e, de acordo com o modelo CCFOM, o termo de fluxo de carga é o responsável pelo efeito no aumento da intensidade de HX. Foram ainda destacados os novos modos vibracionais, dando ênfase ao modo de estiramento da ligação intermolecular. Dos estudos empregando a QTAIM foi possível obter os valores da densidade eletrônica e do Laplaciano da densidade eletrônica e avaliar os valores desses parâmetros nos pontos críticos de ligação em HX e na ligação de hidrogênio intermolecular, comprovando dessa forma a formação dos complexos de hidrogênio. Com os estudos empregando o método dos orbitais naturais de ligação foi avaliada a diferença de energia entre os orbitais π (no acetileno) e o orbital do par de elétrons livres do nitrogênio (em HCN), para as espécies receptoras de próton, e o orbital sigma antiligante do hidrogênio em HX.
APA, Harvard, Vancouver, ISO, and other styles
5

Lacerda, Luis Henrique da Silveira. "INVESTIGAÇÃO TEÓRICA DOS MATERIAIS ZnO:Ba E (Ba, Zn)TiO3." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/2037.

Full text
Abstract:
Made available in DSpace on 2017-07-24T19:37:53Z (GMT). No. of bitstreams: 1 Luis Lacerda.pdf: 6157407 bytes, checksum: 67f47ee9ce5d908521ba3d0455add580 (MD5) Previous issue date: 2015-03-09
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Semiconductors materials are largely employed on development of innumerous optical and electronic due to their electronic, optical, ferroelectric and structural properties. Among the semiconductors materials stand out the zinc oxide (ZnO) and the barium titanate (BaTiO3) once shows excellent properties allied to low cost to obtaining. The ZnO is a simple oxide used in technology and largely investigated as an alternative to replace high cost material on development of electronic devices. Similarly, the BaTiO3 has perovskite crystalline structure whose properties present great technological interest. This work evaluated the effect of Ba presence on wurtzite structure and the influence of Zn atoms on tetragonal BaTiO3 properties. The obtained results indicates that the Ba atoms changes drastically the band structure of ZnO, resulting in the decrease of band gap for low quantities and the semiconductor type modification for doping above 25 %. The insertion of such atoms in wurtzite also causes the improvement of ferroelectric properties and the increase of unit cell lattice parameters. In case of Zn-doped BaTiO3, the doping process reduces radically de band gap and the ferroelectric properties regarding to pure material. Likewise, the semiconductor type is also modified by the Zn atoms presence. Based on obtained results for both crystalline systems, was proposed their employed in formation of p-n heterojunction. The heterostructure was evaluated through of four models. The obtained results for each one of these models were used to describe the interface region of ZnO/BaTiO3 heterojunction, proving that the atoms intercalation occurs and is responsible for heterostructure properties. Such properties present this heterostructure as a potential alternative for development of electronic devices, mainly the development of memory devices. The obtained heterostructure requires a low amount energy to electronic conduction process and shows high compatibility between the structure of heterojunction and the SiO2 substrate which is used in development of such devices.
Materiais semicondutores são amplamente empregados no desenvolvimento de vários dispositivos ópticos e eletrônicos variados devido às suas propriedades eletrônicas, ópticas, ferroelétricas e estruturais. Dentre os materiais semicondutores, destacam-se o óxido de zinco (ZnO) e o Titanato de Bário (BaTiO3) uma vez que apresentam excelentes propriedades aliadas ao baixo custo de síntese. O ZnO é um óxido simples amplamente empregado na tecnologia e largamente investigado como uma alternativa para substituição de materiais de custo elevado no desenvolvimento de dispositivos eletrônicos. Por sua vez, o BaTiO3 é um material de estrutura cristalina perovskita cujas propriedades são de grande interesse tecnológico. No presente trabalho avaliou-se o efeito da presença de átomos de Ba na estrutura wurtzita do ZnO e a influência dos átomos de Zn sobre as propriedades do BaTiO3 tetragonal. Os resultados indicaram que os átomos de bário alteram drasticamente a estrutura de bandas do ZnO, resultando na diminuição do band gap para pequenas quantidades e a modificação do tipo de semicondutor para dopagens superiores a 25%. A inserção de tais átomos na estrutura wurtzita também é responsável pelo aprimoramento das propriedades ferroelétricas do material, bem como pelo aumento dos parâmetros de rede da célula unitária. No caso da estrutura do BaTiO3 dopada com Zn observou-se a redução drástica do band gap para o material e a modificação do caráter semicondutor do material; entretanto, ocorreu a redução das propriedades ferroelétricas em relação ao BaTiO3 puro. Com base nos resultados obtidos para ambos os sistemas cristalinos, propôs-se a sua utilização para formação de uma heterojunção do tipo p-n. A heteroestrutura foi avaliada por meio de quatro modelos diferentes. Os resultados obtidos para cada um destes modelos foram utilizados para descrição da estrutura eletrônica da região de interface da heterojunção, comprovando que a intercalação de átomos na interface é observada e mostra-se responsável pelas propriedades observadas para a heteroestrutura. Tais propriedades apontam a heterojunção ZnO/BaTiO3 como uma alternativa em potencial para aplicação no desenvolvimento de dispositivos eletrônicos e, principalmente, no desenvolvimento de dispositivos de armazenamento de dados, devido a diminuição de energia necessária para condução eletrônica.
APA, Harvard, Vancouver, ISO, and other styles
6

Inglês, Daniella. "ESTRUTURA E PROPRIEDADES ÓPTICAS DO SISTEMA TITANATO-ESTANATO DE ESTRÔNCIO [Sr(Ti1-xSnx)O3 x = 0; 0,25; 0,50; 0,75; 1]." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2013. http://tede2.uepg.br/jspui/handle/prefix/2109.

Full text
Abstract:
Made available in DSpace on 2017-07-24T19:38:09Z (GMT). No. of bitstreams: 1 DaniellaIngles.pdf: 4512280 bytes, checksum: c8619d3eba91fdbec4d26eeb30e24eb9 (MD5) Previous issue date: 2013-03-08
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Titanates have perovskite crystalline structure very known for electrical and optical properties used in the electronic devices such as sensors, capacitors, nonvolatile and dynamic random access memories. In particular, titanates structures are characterized for the ABO3 formula being A crystallographic site formed by 12 atoms neighbors and B crystallographic site formed by 6 atoms neighbors. However, researches about strontium titanate-stannate system are found minimally in the literature. Articles discussing synthesis, characterization and compositions are insufficiently presented. This project shows a theoretical study of the structure and optical properties of the strontium titanate-stannate system for different substitutions [Sr(Ti1-xSnx)O3 x = 0; 0,25; 0,50; 0,75; 1]. It was used theoretical-computational methodology based on, Density Functional Theory (DFT) with B3LYP functional to calculate the structure of the models SrTiO3 (STO), Sr(Ti1-xSnx)O3 (STS) and SrSnO3 (SSO). Theoretical data of parameter lattice, cell unit angles, volume, band gap, overlap population, charges and free energy are presented as well as analysis and discussion of the results for band structure (EB), density of states (DOS), electron density maps. Thus, one may present the data obtained and investigate the properties of the materials.
Titanatos possuem estrutura cristalina perovskita muito conhecida pelas propriedades elétricas e ópticas utilizadas em dispositivos eletrônicos como sensores, capacitores, memória de acesso randômico dinâmica e não volátil. Em particular, as estruturas de titanatos são caracterizadas pela fórmula ABO3 sendo A sítio cristalográfico formado por 12 átomos vizinhos e B o sítio cristalográfico formado por 6 átomos vizinhos. No entanto, pesquisas sobre o sistema titanato-estanato de estrôncio são encontradas minimamente na literatura. Artigos que discutem a síntese, caracterização e composições são insuficientemente apresentados. Este trabalho apresenta o estudo teórico da estrutura e propriedades ópticas do sistema titanato-estanato de estrôncio para diferentes substituições [Sr(Ti1-xSnx)O3 x = 0; 0,25; 0,50; 0,75; 1]. Utilizou-se metodologia teórico-computacional baseada em, Teoria do Funcional de Densidade (DFT) com funcional B3LYP, para cálculo da estrutura dos modelos SrTiO3 (STO), Sr(Ti1-xSnx)O3 (STS) e SrSnO3 (SSO). Dados teóricos de parâmetro de rede, ângulos da célula unitária, band gap, recobrimento populacional, cargas e energia livre são apresentados como também a análise e discussão dos resultados por meio de estrutura de bandas (EB), densidade de estados (DOS), mapas de densidade eletrônica. Desta forma, podem-se apresentar os dados obtidos e investigar as propriedades dos materiais.
APA, Harvard, Vancouver, ISO, and other styles
7

Rönnby, Karl. "Quantum Chemical Feasibility Study of Methylamines as Nitrogen Precursors in Chemical Vapor Deposition." Thesis, Linköpings universitet, Kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-132812.

Full text
Abstract:
The possibility of using methylamines instead of ammonia as a nitrogen precursor for the CVD of nitrides is studied using quantum chemical computations of reaction energies: reaction electronic energy (Δ𝑟𝐸𝑒𝑙𝑒𝑐) reaction enthalpy (Δ𝑟𝐻) and reaction free energy (Δ𝑟𝐺). The reaction energies were calculated for three types of reactions: Uni- and bimolecular decomposition to more reactive nitrogen species, adduct forming with trimethylgallium (TMG) and trimethylaluminum (TMA) followed by a release of methane or ethane and surface adsorption to gallium nitride for both the unreacted ammonia or methylamines or the decomposition products. The calculations for the reaction entropy and free energy were made at both STP and CVD conditions (300°C-1300°C and 50 mbar). The ab inito Gaussian 4 (G4) theory were used for the calculations of the decomposition and adduct reactions while the surface adsorptions were calculated using the Density Functional Theory method B3LYP. From the reactions energies it can be concluded that the decomposition was facilitated by the increasing number of methyl groups on the nitrogen. The adducts with mono- and dimethylamine were more favorable than ammonia and trimethylamine. 𝑁𝐻2 was found to be most readily to adsorb to 𝐺𝑎𝑁 while the undecomposed ammonia and methylamines was not willingly to adsorb.
APA, Harvard, Vancouver, ISO, and other styles
8

Zurek, Eva D. "Density functional theory (DFT) studies of solids and molecules." [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-27968.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Brincat, Nick. "Density functional theory investigation of the uranium oxides." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.665418.

Full text
Abstract:
The aim of this thesis is to provide insight into the structures and properties of the uranium oxides. As UO2 is easily oxidised during the nuclear fuel cycle it is important to have a detailed understanding of the structures and properties of the oxidation products. Experimental work over the years has revealed many stable oxides including UO2, U4O9, U3O7, U2O5, U3O8 and UO3, all with a number of different polymorphs. The oxides are broadly split into two categories, fluorite-based structures with stoichiometries in the range of UO2 to U2O5 and less dense layered-type structures with stoichiometries in the range of U2O5 to UO3. While UO2 is well characterised, both experimentally and computationally, there is a paucity of data concerning higher stoichiometry oxides in the literature. Experiments and simulations are emerging that deal with individual phases, however a comprehensive study that assesses the properties of all polymorphs and provides comparison over the full range of stoichiometries has been lacking from the literature First the nuclear fuel cycle is introduced, as well as UO2 as a nuclear fuel (Chapter 1), before the quantum mechanical methodology used throughout is explained (Chapter 2). Applying a number of different density functionals (including GGAs, meta-GGAs and hybrids) to UO2 in Chapter 3 it emerges that the PBE + U formalism reproduces the experimentally observed properties to a good degree of accuracy, and so is selected for the rest of the simulations. Following this Chapter 4 examines defect clusters in UO2, finding split interstitials to dominate at low stoichiometry (UO2 – UO2.0625), chains of 2:2:2 Willis clusters at higher stoichiometry (UO2.125 – UO2.25 (U4O9)) and split quad interstitials at higher stoichiometry (UO2.33 (U3O7)). Chapter 5 is an investigation of layered U2O5, where it emerges that the Np2O5 structure is more stable than δ-U2O5 and all uranium ions are in the U5+ oxidation state. Next Chapter 6 considers layered U3O8, which is structurally oxygen rich U2O5, where it is found that U5+ and U6+ ions exist in pentagonal bipyramidal and octahedral coordination respectively. The final set of results in Chapter 7 concern the polymorphs of UO3, where it is found that U6+ adopts a range of coordination environments and the predicted relative stability of each modification matches well with experiment. Finally the conclusions are presented in Chapter 8 along with plans for future work.
APA, Harvard, Vancouver, ISO, and other styles
10

Reinhold, Meike. "A DFT study of organometallic reaction mechanisms." Thesis, University of York, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247161.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Density Functional Theory - DFT/B3LYP"

1

Eriksson, Olle, Anders Bergman, Lars Bergqvist, and Johan Hellsvik. Density Functional Theory. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198788669.003.0001.

Full text
Abstract:
Density functional theory (DFT) has established itself as a very capable platform for modelling from first principles electronic, optical, mechanical and structural properties of materials. Starting out from the Dirac equation for the many-body system of electrons and nuclei, an effective theory has been developed allowing for materials specific and parameter free simulations of non-magnetic and magnetic solid matter. In this Chapter an introduction will be given to DFT, the Hohenberg-Kohn theorems, the Kohn-Sham equation, and the formalism for how to deal with non-collinear magnetism.
APA, Harvard, Vancouver, ISO, and other styles
2

Launay, Jean-Pierre, and Michel Verdaguer. Basic concepts. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198814597.003.0001.

Full text
Abstract:
The electronic structure of molecules is described, starting from qualitative Molecular Orbital (MO) theory. After the case of simple atoms and molecules, one treats molecular solids and develops the relation between Molecular Orbital theory and band theory. In both cases, one shows that the electronic structure can influence the geometrical structure, through Jahn–Teller effects or Peierls distortion. The effect of interelectronic repulsion, the central problem of Quantum Chemistry, is put in perspective by a synthetic presentation of different approaches: Hartree–Fock Self-Consistent Field with treatment of electron correlation, Valence Bond models, and finally Density Functional Theory methods (DFT). The last section is devoted to quantum tunnelling and its dynamical aspects.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Density Functional Theory - DFT/B3LYP"

1

Gulati, Archa, and Rita Kakkar. "6. DFT studies on storage and adsorption capacities of gases on MOFs." In Density Functional Theory, edited by Ponnadurai Ramasami, 83–112. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110568196-006.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Palafox, M. Alcolea. "10. DFT computations on vibrational spectra: Scaling procedures to improve the wavenumbers." In Density Functional Theory, edited by Ponnadurai Ramasami, 147–92. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110568196-010.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Dhar, Namrata, and Debnarayan Jana. "5. A DFT perspective analysis of optical properties of defected germanene mono-layer." In Density Functional Theory, edited by Ponnadurai Ramasami, 65–82. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110568196-005.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

de Boeij, P. L. "Solids from Time-Dependent Current DFT." In Time-Dependent Density Functional Theory, 287–300. Berlin, Heidelberg: Springer Berlin Heidelberg, 2006. http://dx.doi.org/10.1007/3-540-35426-3_19.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Chowdhury, Suman, and Debnarayan Jana. "1. Optical properties of monolayer BeC under an external electric field: A DFT approach." In Density Functional Theory, edited by Ponnadurai Ramasami, 1–18. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110568196-001.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Sahni, Viraht. "Application of Q-DFT to Atoms in Excited States." In Quantal Density Functional Theory II, 249–62. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92229-2_13.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Sahni, Viraht. "Application of Q-DFT to the Metal–Vacuum Interface." In Quantal Density Functional Theory II, 303–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92229-2_17.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Sahni, Viraht. "Application of the Q-DFT Hartree Uncorrelated Approximation to Atoms." In Quantal Density Functional Theory II, 167–86. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92229-2_9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Kavitha, Helen P., Lydia Rhyman, and Ponnadurai Ramasami. "8. Molecular structure and vibrational spectra of 2-(4-bromophenyl)-3-(4-hydroxyphenyl) 1,3-thiazolidin-4-one and its selenium analogue: Insights using HF and DFT methods." In Density Functional Theory, edited by Ponnadurai Ramasami, 123–34. Berlin, Boston: De Gruyter, 2018. http://dx.doi.org/10.1515/9783110568196-008.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Sahni, Viraht. "Application of the Q-DFT Fully Correlated Approximation to the Helium Atom." In Quantal Density Functional Theory II, 275–88. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92229-2_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Density Functional Theory - DFT/B3LYP"

1

Andrade, Maria Andreizi Monteiro de, Iran da Luz Sousa, and Régis Casimiro Leal. "Heats of Formation for Iodine Compounds: A DFT Study." In VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020181.

Full text
Abstract:
The heat formation of 33 molecules for the iodine compounds were performed using the functional density theory (DFT) (B3LYP, M06-2X and WB97XD), and the basis sets (6-311G (d, p) and cc-pVQZ + d). The best agreement with experimental data was achieved by using B3LYP/cc-pVQZ+d, WB97XD/6-311G (d,p) and MP2/6-311G (d,p).
APA, Harvard, Vancouver, ISO, and other styles
2

Carvalho, Francisco Dheyson de Quadro, and Estevão Bombonato Pereira. "Estudo fotofísico do Luminol." In VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020138.

Full text
Abstract:
The 5-Amino-2,3-dihydro-1,4-phthalazinedione known as Luminol is used mainly in hidden blood investigations. Therefore, the objective of this work is to develop a calculations routine using computational chemistry methods that properly describe the structure of luminol and its derivatives. Posteriorly, this routine will be used for the analysis and the proposition of new structures comparing the results with experimental data obtained in appropriate literature. Firstly, the Density Functional Theory (DFT) was used with the functional B3LYP/G, and the base function def2-TZVP in the ORCA program for modeling the structures. Thus, was verified the interference of the presence of solvent molecules close to the luminol molecule, the use of solvent as a dielectric continuum, the combination of both for a description of the solvent effect, and the use of relativistic functions to optimize results. Therefore, having obtained the preliminary results, we did the comparison with experimental data collected by other researchers.
APA, Harvard, Vancouver, ISO, and other styles
3

Yanagida, Shozo, and Takeko Matsumura. "Quantum chemistry molecular modeling for radio-frequency and microwave- frequency thermo-upconversion heating of metal oxides of NiO and Fe2O3." In Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.10234.

Full text
Abstract:
Under irradiance of 1kW-MW, nickel oxide (Ni(II)O, 25 gr)) can heat up to 1,300°C in 6 min, while ferric oxide (Fe(III)2O3, 25gr) up to 88°C in 30 min. Since Ni(II) and Fe(III) have unpaired electron (spin) of respective 2 and 5, the big difference in the MW heating speed must be explained by thermo-upconversion mechanism as recently verified for quick MW heating of water clusters.1) MW heating power by magnetic loss factor of magnetic metal oxides with unpaired electron, i.e., spin dcould not rationalize such heating-speed and temperature difference. Density functional theory-based molecular modeling(DFT/MM, B3LYP, 6-31G*) of NiO-tetramer of [(NiO)2]2 is successfully carried out with negative heat of formation, giving effective absorption in both FIR and IR regions, which verifies that Ni(II)O should be heated up through thermo-upconversion to the IR region via radio-, MW- and FIR-absorption, i.e., FIR/IR absorption and thermal IR dissipation
APA, Harvard, Vancouver, ISO, and other styles
4

Shafagh, I., K. J. Hughes, M. Pourkashanian, and A. Williams. "Application of Ab Initio Quantum Mechanical Calculations to Investigate Oxidation of C-7 and C-14 Methyl Esters: An Alternative Fuel." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11255.

Full text
Abstract:
Using Gaussian 03 [1] program the electronic structure of the C-14 methyl ester, C14H28O2 (methyl tridecanoate), one of the components of biodiesel and the species involved in the unimolecular and bimolecular decompositions of it were estimated. For the electronic calculations the density functional theory (DFT) at B3LYP/6-311G(d, p) level and complete basis set (CBS-QB3) were applied. Using the KHIMERA program [2], contributions from energies, harmonic vibrational frequencies and moments of inertia were utilized to construct modified Arrhenius rate expressions for bimolecular reactions. C7H14O2 was selected as a surrogate for the C14H28O2 fuel in order to study the bimolecular reactions with flame radicals. In the present work reactions of carbons number 5 and 6 of C7H14O2, where carbon number 1 is the one single bonded to oxygen atom, with flame reactive radicals such as CH3, HO2 and H were studied. The rate expressions for the cited reactions were estimated using transition state theory as implemented in KHIMERA, over the temperature 500–2000 K. Heat of reactions for unimolecular decompositions were also calculated and compared to those from Methyl Butanoate (MB).
APA, Harvard, Vancouver, ISO, and other styles
5

Kazemiabnavi, Saeed, Prashanta Dutta, and Soumik Banerjee. "Ab Initio Modeling of the Electron Transfer Reaction Rate at the Electrode-Electrolyte Interface in Lithium-Air Batteries." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-40239.

Full text
Abstract:
Lithium-air batteries are very promising energy storage systems for meeting current demands in electric vehicles. However, the performance of these batteries is highly dependent on the electrochemical stability and physicochemical properties of the electrolyte such as ionic conductivity, vapor pressure, static and optical dielectric constant, and ability to dissolve oxygen and lithium peroxide. Room temperature ionic liquids, which have high electrical conductivity, wide electrochemical stability window and also low vapor pressure, are considered potential electrolytes for these batteries. Moreover, since the physicochemical and electrochemical properties of ionic liquids are dependent on the structure of their constitutive cations and anions, it is possible to tune these properties by choosing from various combinations of cations and anions. One of the important factors on the performance of lithium-air batteries is the local current density. The current density on each electrode can be obtained by calculating the rate constant of the electron transfer reactions at the surface of the electrode. In lithium-air batteries, the oxidation of pure lithium metal into lithium ions happens at the anode. In this study, Marcus theory formulation was used to calculate the rate constant of the electron transfer reaction in the anode side using the respective thermodynamics data. The Nelsen’s four-point method of separating oxidants and reductants was used to evaluate the inner-sphere reorganization energy. In addition, the Conductor-like Screening Model (COSMO) which is an approach to dielectric screening in solvents has been implemented to investigate the effect of solvent on these reaction rates. All calculations were done using Density Functional Theory (DFT) at B3LYP level of theory with a high level 6-311++G** basis set which is a Valence Triple Zeta basis set with polarization and diffuse on all atoms (VTZPD) that gives excellent reproducibility of energies. Using this methodology, the electron transfer rate constant for the oxidation of lithium in the anode side was calculated in an ionic liquids electrolyte. Our results present a novel approach for choosing the most appropriate electrolyte(s) that results in enhanced current densities in these batteries.
APA, Harvard, Vancouver, ISO, and other styles
6

Mattsson, Thomas R., Rudolph J. Magyar, Mark Elert, Michael D. Furnish, William W. Anderson, William G. Proud, and William T. Butler. "DENSITY FUNCTIONAL THEORY (DFT) SIMULATIONS OF SHOCKED LIQUID XENON." In SHOCK COMPRESSION OF CONDENSED MATTER 2009: Proceedings of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP, 2009. http://dx.doi.org/10.1063/1.3295261.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Tachikawa, Hiroto, Tetsuji Iyama, and Hiroshi Kawabata. "Molecular design of functionalized fullerenes and graphenes: Density functional theory (DFT) study." In 2016 Compound Semiconductor Week (CSW) [Includes 28th International Conference on Indium Phosphide & Related Materials (IPRM) & 43rd International Symposium on Compound Semiconductors (ISCS)]. IEEE, 2016. http://dx.doi.org/10.1109/iciprm.2016.7528697.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Dincer, S., M. S. Dincer, H. Duzkaya, and S. S. Tezcan. "Analysis of Molecular Orbital Properties of SF6 with Density Functional Theory (DFT)." In 2019 3rd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT). IEEE, 2019. http://dx.doi.org/10.1109/ismsit.2019.8932772.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Iyama, Tetsuji, Hiroshi Kawabata, Takahiro Fukuzumi, and Hiroto Tachikawa. "Electronic states of organic radical-functionalized graphenes and fullerenes: Density functional theory (DFT) study." In 2016 Compound Semiconductor Week (CSW) [Includes 28th International Conference on Indium Phosphide & Related Materials (IPRM) & 43rd International Symposium on Compound Semiconductors (ISCS)]. IEEE, 2016. http://dx.doi.org/10.1109/iciprm.2016.7528698.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Huang, Lulu, Andrew Shabaev, Samuel G. Lambrakos, Noam Bernstein, Verne L. Jacobs, Daniel Finkenstadt, and Lou Massa. "Dielectric Response of β-HMX at THz Frequencies Calculated by Density Functional Theory." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-47669.

Full text
Abstract:
We present calculations of ground state resonance structure associated with the high explosives β-HMX using density functional theory (DFT), which is for the construction of parameterized dielectric response functions for excitation by electromagnetic waves at compatible frequencies. These dielectric functions provide for different types of analyses concerning the dielectric response of explosives. In particular, these dielectric response functions provide quantitative initial estimates of spectral response features for subsequent adjustment with respect to additional information such as laboratory measurements and other types of theory based calculations. With respect to qualitative analysis, these spectra provide for the molecular level interpretation of response structure. The DFT software GAUSSIAN was used for the calculations of ground state resonance structure presented here.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Density Functional Theory - DFT/B3LYP"

1

Root, Seth, John H. Carpenter, Kyle Robert Cochrane, and Thomas Kjell Rene Mattsson. Equation of state of CO2 : experiments on Z, density functional theory (DFT) simulations, and tabular models. Office of Scientific and Technical Information (OSTI), October 2012. http://dx.doi.org/10.2172/1055894.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Carpenter, John H., Seth Root, Kyle Robert Cochrane, Dawn G. Flicker, and Thomas Kjell Rene Mattsson. Equation of state of argon : experiments on Z, density functional theory (DFT) simulations, and wide-range model. Office of Scientific and Technical Information (OSTI), August 2012. http://dx.doi.org/10.2172/1055655.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Miller, Michael E. A Density Functional Theory (DFT) Study of the Proposed Insensitive High Energy Density Material (IHEDM) 2-(Nitroaminomethylene)-4,5-Dinitrocyclopenta-3,5-Di-Nitroamine (NDDN). Fort Belvoir, VA: Defense Technical Information Center, October 2011. http://dx.doi.org/10.21236/ada551809.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Weinlandt, Thomas, Dan Kaplan, and Venkataraman Swaminathan. A Method to Formulate the Unit Cell for Density Functional Theory (DFT) Calculations of the Electronic Band Structure of Heterostructures of Two-dimensional Nanosheets. Fort Belvoir, VA: Defense Technical Information Center, April 2015. http://dx.doi.org/10.21236/ada623945.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography