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Tytuł:
A Hybrid Density Functional Study on PuN
Autorzy:
Yang, Rong
Tang, Bin
Gao, Tao
Powiązania:
https://bibliotekanauki.pl/articles/1029819.pdf
Data publikacji:
2018-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
plutonium mononitride
density-functional theory
hybrid functional
Opis:
The structural, magnetic, electronic, dynamical and thermodynamic properties of PuN have been studied within the frameworks of the density-functional theory, DFT+U and hybrid DFT. The calculations have been performed using the full-potential-linearized augmented plane-wave method. The ferromagnetic and antiferromagnetic configurations are considered in this work. The lattice constants, bulk moduli, densities of states, and thermodynamic data have been computed and compared to available experimental data and other theoretical calculations published in the literature. Total energy results obtained with DFT+U and hybrid DFT indicate that the ground state of PuN is antiferromagnetic, in agreement with experiment. The chemical bonds between Pu and N have a mixture of covalent and ionic components, but the ionic character is stronger than covalent character. The phonon dispersion curves and the optical-mode frequencies are also reported. At last, the effect of spin-orbit coupling on the structural, magnetic, and electronic properties of PuN has been discussed.
Źródło:
Acta Physica Polonica A; 2018, 133, 1; 32-38
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adsorption of hydrated Fe(OH)2+ on the kaolinite surface: A density functional theory study
Autorzy:
Wu, Hongqiang
Miao, Yuqi
Long, Qibang
Yan, Huashan
Li, Yong
Qiu, Sen
Wu, Hao
Zhao, Guanfei
Qiu, Tingsheng
Powiązania:
https://bibliotekanauki.pl/articles/27323639.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
kaolinite
adsorption
Fe
density functional theory
Opis:
The present study employed density functional theory (DFT) to analyze the adsorption configuration and mechanism of Fe(OH)2+ on the kaolinite (001) surface. The findings demonstrated that Fe(OH)2(H2O)4+ is the main type in which hydrated Fe(OH)2+ can be found in aqueous solution. On the surface of kaolinite, Fe(OH)2(H2O)4+ will be adsorbed. There are two forms of adsorption: outer-sphere and inner-sphere coordination (monodentate/bidentate) adsorption. Fe(OH)2(H2O)4+ has a moderate propensity to adsorb on the alumina octahedral sheet of kaolinite when the outer-sphere coordination adsorption takes place. In cases of inner-sphere coordination adsorption, Fe exhibits a tendency to form monodentate adsorption compounds in conjunction with Ou atoms. Additionally, it prefers to create bidentate adsorption compounds through coordination with both Ot and Ou atoms. The adsorption mechanism analysis results show that the ionic property of Fe atom decreases after outer-sphere coordination adsorption. After inner-sphere coordination adsorption, some electrons of Fe atom are transferred to the surface O atom. The presence of electrons between the Fe and O atoms enhances the formation of bonds, hence enhancing the covalent nature of the Fe-O bond. Theoretical FT-IR (Fourier transform infrared spectroscopy) calculations show that the formation of Fe-O chemical bonds. Because of the lower adsorption energy and more chemical bonds, hydrate Fe(OH)2+ is more likely to be bidentate adsorbed on the kaolinite surface.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 6; art. no. 174415
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Theoretical Studies of a New High Explosive, N,N,-Bis(3-aminofurazan-4-yl)-4,4´-diamino- 2,2´,3,3´,5,5´,6,6´-octanitroazobenzene
Autorzy:
Jing, S.
Liu, Y.
Liu, D.
Guo, J.
Powiązania:
https://bibliotekanauki.pl/articles/358642.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
BAFDAONAB
density functional theory
detonation properties
Opis:
A new high energy, low sensitivity material N,N,-bis(3-aminofurazan- 4-yl)-4,4´-diamino-2,2´,3,3´,5,5´,6,6´-octanitroazobenzene (BAFDAONAB) was synthesized from 4-chlorobenzoic acid and diaminofurazan. The structure of BAFDAONAB was characterized by FT-IR, NMR and Elemental Analyses and its purity was determined by HPLC. The optimized structure and thermodynamic parameters were obtained at the DFT- B3LYP/6-31+G** theoretical level. Its detonation properties were also predicted by the formulae of Kamlet-Jacobs and the Monte-Carlo method. The results show that the density, heat of formation, detonation velocity, detonation pressure, impact sensitivity and purity were 1.93 g/cm3, 4487.44 kJ/mol, 9.01 km/s, 35.03 GPa, 63 cm and 99.3%, respectively. In addition, the compound was an insensitive high explosive which could meet the requirements of high energetic materials.
Źródło:
Central European Journal of Energetic Materials; 2015, 12, 4; 745-755
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Density functional simulation of metal oxides: $Al_2O_3$ and $Fe_3O_4$
Autorzy:
Łodziana, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2028983.pdf
Data publikacji:
2004
Wydawca:
Politechnika Gdańska
Tematy:
density functional theory
metal oxides
alumina
magnetite
Opis:
The study of the metal oxides is a rapidly developing area of research. Below a theoretical method based on the density functional theory, common in studying ceramics, is briefly presented. Application of the theory to the surface and the bulk properties of alumina and magnetite are presented. Relaxation mechanism of two different surfaces of alumina and the (100) surface of Fe3O4 are shown. The mutual stability of the ? and ? phases of Al2O3 is calculated.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2004, 8, 4; 561-572
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Density functional theory study of H2O adsorption on different sphalerite surfaces
Autorzy:
Deng, Zheng-bin
Tong, Xiong
Huang, Ling-yun
Xie, Xian
Powiązania:
https://bibliotekanauki.pl/articles/110593.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
density functional theory
sphalerite
water adsorption
hydrophobicity
Opis:
Effects of In, Ge, Fe substitution in the lattice of sphalerite on wettability were usually ignored, therefore the optimal flotation condition could be difficult to find due to lacking of sufficient theoretical study on water adsorption, resulting lower recoveries of different sphalerites. Adsorption of H2O on different sphalerite surfaces was studied using density functional theory (DFT) method. All computational models were built in a vacuum environment to eliminate the effects of oxygen and other factors. H2O molecule prefers to stay with ideal sphalerite, indium-beard sphalerite, germanium-beard sphalerite and marmatite surfaces rather than water. Compared with ideal sphalerite surface, Fe atom improves the hydrophilicity of surface, while In and Ge atoms reduce the hydrophilicity.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 1; 82-88
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Insights into the interaction between octyl hydroxamic acid and the rutile surface activated by lead ion
Autorzy:
Cao, Qinbo
Chen, Xiumin
Zou, Heng
Yu, Xingcai
Powiązania:
https://bibliotekanauki.pl/articles/1845214.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
flotation
rutile
activation
density functional theory
adsorption
Opis:
The flotation of rutile can be enhanced using lead ion as an activator. However, the binding behavior of collector on the activated rutile surface is still not fully understood. In this work, flotation and theoretical calculation approaches were employed to evaluate the activation behavior of lead ion in the flotation of rutile with octyl hydroxamic acid (OHA). Flotation results indicated that the activation flotation with lead ion should be conducted at pH 6.5. The binding features of OHA molecule on the inactivated and Pb-activated rutile surfaces were both investigated by density functional theory (DFT) studies. The OHA molecule may dissociate into OHA− anion on the inactivated rutile surface, generating a new Ti–O bond. Differently, the chelate complex of Pb-OHA anion was generated on the activated rutile surface, producing two Pb–O bonds. The adsorption of OHA onto the activated rutile surface was more stable than that on the inactivated rutile surface, due to the formation of more chemical bonds on the activated rutile surface. The DFT calculation results delineated the role of Pb2+ in the rutile flotation with OHA.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 5; 928-938
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Flotation separation of cervantite from quartz
Autorzy:
Wang, J.
Hua, Y.
Yu, S.
Xiao, J.
Xu, L.
Wang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/110941.pdf
Data publikacji:
2017
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cervantite
quartz
dodecylamine
flotation
density functional theory
Opis:
Flotation separation of cervantite (Sb2O4) from quartz was investigated using dodecylamine (DDA) as a collector. Experiments were conducted on single minerals and on a synthetic mixture of quartz and cervantite. Flotation separation mechanisms were investigated using the zeta potential technique, solution chemistry principles, density functional calculations and Fourier Transform Infrared (FT-IR) spectroscopy. The results indicated that DDA, primarily in the form of molecules, exhibited excellent performance in flotation of cervantite and quartz at pH 10.5. The adsorption energy of the DDA molecules on the cervantite surface was greater than the adsorption energy of water molecules, while the adsorption energy of DDA on the quartz surface was less than the adsorption energy of water molecules. DDA molecules can be adsorbed on the quartz surface to a certain extent, but it was difficult for the same molecule to be adsorbed on the cervantite surface in the pulp. This resulted in flotation of quartz. DDA molecules were adsorbed on quartz not only through physical adsorption but also by hydrogen bonding. However, cervantite could not be floated at pH 10.5 since adsorption of DDA molecules occurred through weak physical bonds on cervantite.
Źródło:
Physicochemical Problems of Mineral Processing; 2017, 53, 2; 1119-1132
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interaction of sulfuric acid with dolomite (104) surface and its impact on the adsorption of oleate anion: a DFT study
Autorzy:
Cao, Qinbo
Zou, Heng
Chen, Xiumin
Yu, Xingcai
Powiązania:
https://bibliotekanauki.pl/articles/1449558.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
dolomite
adsorption
oleate
depressor
density functional theory
Opis:
Sulfuric acid $(H_2SO_4)$ is a specific depressor for apatite rather than for dolomite. The $H_2SO_4$ treated dolomite can still be floated effectively by oleate. However, the role of $H_2SO_4$ in the adsorption of oleate onto dolomite surface remains unclear. In this work, density functional theory calculations were conducted to probe the interactions among sulfate anion ($SO_4^{2−}$), oleate anion and the dolomite surface. The adsorption behaviors of $SO_4^{2−}$ anion onto the perfect and $CO_3$-defect dolomite surfaces were compared. Such results show that $SO_4^{2−}$ anion could only adsorb onto the defective dolomite surface, where it bonded with a $Ca$ atom. The remaining $Ca$ and $Mg$ atoms at the defect site could further react with the oleate anion, generating new $Ca$/$Mg–O$ ionic bond. In this regard, oleate and $SO_4^{2−}$ anions may both present on the dolomite surface. This phenomenon accounts for the flotation of $H_2SO_{4-}$treated dolomite.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 34-42
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of flocculation performance and mechanism of ultrafine montmorillonite particles with NPAM
Autorzy:
Wang, Lujun
Min, Fanfei
Chen, Jun
Wang, Ting
Zhou, Zhuang
Powiązania:
https://bibliotekanauki.pl/articles/2146901.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
montmorillonite
flocculant
nonionic polyacrylamide
density functional theory
Opis:
Ultrafine montmorillonite particles are the main clay minerals in industrial wastewater. In order to explore the flocculation performance and mechanism of flocculant with montmorillonite, the effects of nonionic polyacrylamide (NPAM) dosage and molecular weight on flocculation effect were studied using a flocculation sedimentation experiment. The morphology of flocs was observed by metallographic microscope and scanning electron microscope, and the microscopic adsorption mechanism was studied utilizing density functional theory (DFT). The results show that the best reagent system for the montmorillonite sample is that the molecular weight of NPAM is 14 million and the added amount is 100 g/t. The floc size increases with rising NPAM dosage, forming a unique multi-level compact space network structure through polymer bridging. The adsorption energy of acrylamide on the Na-(001) surface of montmorillonite is -108.81 kJ/mol, which is significantly higher than -50.66 kJ/mol on the None-(001) surface. Hydrogen bonding is not the main reason for the adsorption of acrylamide on the montmorillonite surface. NPAM mainly causes the flocculation and sedimentation of montmorillonite through the processes of polymer bridging and electrostatic attraction. This study can provide a theoretical basis for the design and synthesis of new flocculants.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 3; art. no. 147790
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Aminonitronaphthalenes as Possible High Energy Density Materials
Autorzy:
Murawski, R. J.
Ball, D. W.
Powiązania:
https://bibliotekanauki.pl/articles/358002.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
high energy density materials
aminonitronaphthalenes
density functional theory calculations
Opis:
As part of a series of studies evaluating the thermodynamic properties of new potential high energy materials, a series of calculations was performed on a variety of naphthalene molecules having amino and nitro groups. Calculations on seven aminonitronaphthalene molecules were performed, determining their minimum-energy geometries, vibrational frequencies, and energies. Enthalpies of formation were determined using atomization reactions, and subsequently enthalpies of combustion or decomposition were determined. Specific enthalpies of decomposition ranged from 4.1-4.8 kJ/g, while specific enthalpies of combustion ranged more widely, from 13 to almost 21 kJ/g. Some detonation properties of some of the derivatives rival those of current HEDMs.
Źródło:
Central European Journal of Energetic Materials; 2015, 12, 1; 3-12
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hydrogen storage on graphene sheet: physisorption, diffusion and chemisorbed pathways by first principles calculations
Magazynowanie wodoru na arkuszu grafenu: analiza ścieżek fizykosorpcji, dyfuzji i chemisorpcji metodą obliczeń ab initio
Autorzy:
Costanzo, F.
Silvestrelli, P.L.
Ancilotto, F.
Powiązania:
https://bibliotekanauki.pl/articles/356177.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
density functional theory
first principles
physisorption and chemisorption
Opis:
Hydrogen is frequently touted as the "fuel of the future" because of its huge potential as clean energy source, although the large-scale adoption of this technology has yet to be realized. One of the remaining barriers to the utilization of hydrogen energy is an efficient and inexpensive means of hydrogen storage. In this work we investigate the nature of this process by first principle calculation. In particular, we study the way in which the H2 molecule can interact with graphene sheet through physisorption and chemisorption mechanism. The first mechanism involves the condensation of the hydrogen molecule on the graphene as a result of weak van der Waals forces, while the chemisorption mechanism involves the preliminary dissociation of the H2 molecule and the subsequent reaction of hydrogen atoms with the unsatured C-C bonds to form C-H bonds. To study carefully the possible physisorbed configurations on the graphene sheet, we take in to account van der Waals (vdW) interactions in DFT using the new method (DFT/vdW-WF) recently developed in our group and based on the concept of maximally localized Wannier functions. There are three possible way in which the H2 molecule can adapt to the structure of graphene: the hollow, the bridge and the top site called H, B and T configurations, respectively. We find the hollow site to be most stable physisorbed state with a binding energy of -50 meV. This value, in agreement with experimental results, is also compared with other vdW-correction methods as described in the following paper. Diffusion of the physisorbed configurations on the graphene sheet and activated reaction pathways in which the molecule starts from a physisorbed configuration to end up in a chemisorbed configurations have also been studied.
Ze względu na możliwość magazynowania wodoru na arkuszu grafenu, badamy nature tego procesu metoda obliczeń ab initio. Cząsteczka H2 może oddziaływać z grafenem na dwa sposoby: fizykosorpcje i chemisorpcje. Mechanizm fizykosorpcji polega na kondensacji cząsteczki wodoru na grafenie na skutek słabych oddziaływań van der Waalsa, podczas gdy mechanizm chemisorpcji polega na wstępnej dysocjacji cząsteczki H2 i następnie reakcji atomów wodoru z niewysyconymi wiązaniami C-C co umożliwia tworzenie wiązań C-H. W celu zobrazowania mechanizmu fizykosorpcji cząsteczek H2 na arkuszu grafenu, analizujemy oddziaływania van der Waalsa (vdW) stosujac teorie funkcjonału gestości (DFT) za pomocą nowej metody (DFT/vdW-WF) niedawno opracowanej w naszej grupie na podstawie koncepcji maksymalnie zlokalizowanych funkcji Wanniera. Analizujemy możliwość absorpcji w różnych miejscach siatki grafenu i orientacje cząsteczki H2 w stosunku do płaszczyzny siatki grafenu. Najbardziej stabilnym miejscem fizykosorbcji jest wnętrze pierścienia grafenu z energia wiązania -50 meV. Wartość ta, zgodna z wynikami doświadczeń, jest także porównywana wartości uzyskanych innymi metodami korekcji vdW. Typowe bariery energetyczne charakteryzujące ścieżkę dyfuzji, są rzędu ∼10 meV. Sytuacja jest inna, gdy cząsteczki wodoru pokonują barierę energetyczna i chemisorbują jako jeden atom wodoru na powierzchni grafenu. Bariery energetyczne w tym przypadku wynoszą około 2-3 eV, w zależności od wybranej ścieżki reakcji.
Źródło:
Archives of Metallurgy and Materials; 2012, 57, 4; 1075-1080
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An atomic scale investigation of the adsorption of sodium oleate on Ca2+ activated quartz surface
Autorzy:
Gong, Guichen
Liu, Jie
Han, Yuexin
Zhu, Yimin
Powiązania:
https://bibliotekanauki.pl/articles/949736.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quartz
sodium oleate
Ca(OH)+
density functional theory
Opis:
In this study, the surface properties and flotation behavior of quartz with NaOl as a collector in the presence of Ca2+ ions were investigated using density functional theory (DFT) calculations in conjunction with flotation tests, adsorption experiments, zeta potential measurements, and solution chemistry calculations. The results of the flotation and adsorption tests proved that Ca2+ promoted the flotation recovery and the adsorption density of sodium oleate on quartz at pH > 8. Zeta potential analyses and solution chemistry calculations demonstrated that Ca(OH)+ was the functional species which activated quartz. DFT calculations indicated that O atoms dominated the quartz (101) surface, and great electrostatic repulsion and space resistance existed between the surface and oleate anion.The spontaneous adsorption of H2O and OH- on the (101) surface made quartz surfaces hydrated and hydroxylated, and resulted in the hydrophilicity of quartz. The adsorption of Ca(OH)+ on quartz (101) surface was more favorable and able to repulse the water film, which decreased the electrostatic repulsion and space resistance, and further facilitated the adsorption of oleate anion. During the activating and collecting adsorption processes, electron transition occurred along the O1—Ca—O2 path, implying Ca(OH)+ acted as an intermediary and electron donator in the activation process.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 2; 426-436
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Simulation of optical spectra of novel Tl4CdI6 and Tl4HgI6 optoelectronic crystals
Autorzy:
Franiv, V
Bovgyra, O
Kushnir, O
Franiv, A
Plucinski, K J
Powiązania:
https://bibliotekanauki.pl/articles/173547.pdf
Data publikacji:
2014
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
density functional theory
band structure
density of states
optical properties
Opis:
The results of calculations using local density approximation and generalized gradient approximation: the total energy depending on the volume of the unit cell, the distribution of the total density of states and the partial contributions of electronic orbitals in the band structure of Tl4CdI6 and Tl4HgI6 crystals are shown in this paper. The spectra of the real part of the dielectric permittivity, the spectra of the imaginary part of permittivity, the reflection spectra and the absorption coefficient of both crystals are obtained using the Kramers–Kronig method. A comparative analysis of theoretical calculations with experimental data is carried out. Substantial influence of electron–phonon broadening is shown.
Źródło:
Optica Applicata; 2014, 44, 2; 317-326
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Theoretical Study of Polyethylene Glycol Polynitrates as Potential Highly Energetic Plasticizers for Propellants
Autorzy:
Wang, Guixiang
Xu, Yimin
Zhang, Wenjing
Gong, Xuedong
Powiązania:
https://bibliotekanauki.pl/articles/358877.pdf
Data publikacji:
2019
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
polyethylene glycol polynitrates
density functional theory
density
specific impulse
stability
Opis:
Polyethylene glycol polynitrates may be used as plasticizers in propellants. In this study, ten derivatives of ethylene glycol dinitrate were investigated using the density functional theory method. The fitted densities (ρ’exp.) were obtained and were very close to the experimental values. The detonation properties were predicted using the modified Kamlet-Jacobs equations and the specific impulse (Is) was evaluated according to the largest exothermic principle. A new indicator, K = Is · ρ’exp., is proposed to evaluate the energetic characteristics of the plasticizers. Thermal stability is discussed by calculating the bond dissociation energies or energy barriers. The O−NO2 bond is the trigger bond for all of the compounds studied. Considering the energetic properties and stability, diethylene glycol tetranitrate, triethylene glycol hexanitrate, tetraethylene glycol octanitrate, pentaethylene glycol decanitrate and hexaethylene glycol dodecanitrate are potential energetic plasticizers for solid propellants. The influences of the −O−CH2−CH2− and −O−CH(ONO2)−CH(ONO2)− groups are also discussed, which will be helpful for the design of new highly energetic plasticizers by modifying the structures as required.
Źródło:
Central European Journal of Energetic Materials; 2019, 16, 2; 194-215
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DFT studies on the electronic structures of 4-methoxybenzonitrile dye for Dye-Sensitized Solar Cell
Autorzy:
Prakasam, A
Sakthi, D
Anbarasan, P.M.
Powiązania:
https://bibliotekanauki.pl/articles/412205.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Dye sensitizer
density functional theory
electronic structure
absorption spectrum
Opis:
The geometries, electronic structures, polarizabilities and hyperpolarizabilities of organic dye sensitizer 4-methoxybenzonitrile was studied based on ab initio HF and Density Functional Theory (DFT) using the hybrid functional B3LYP. Ultraviolet-visible (UV-Vis) spectrum was investigated by Time Dependent DFT (TDDFT). Features of the electronic absorption spectrum in the visible and near-UV regions were assigned based on TDDFT calculations. The absorption bands are assigned to π→π* transitions. Calculated results suggest that the three excited states with the lowest excited energies in 4-methoxybenzonitrile is due to photoinduced electron transfer processes. The interfacial electron transfer between semiconductor TiO2 electrode and dye sensitizer 4-methoxybenzonitrile, is due to an electron injection process from excited dye to the semiconductor’s conduction band. The role of nitro group in 4-methoxybenzonitrile in geometries, electronic structures, and spectral properties were analyzed.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 7, 1; 8-22
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 44

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