A catalytic role of surface silanol groups in CO2 capture on the amine-anchored silica support

A new mechanism of CO2 capture on the amine-functionalized silica support is demonstrated using density functional theory calculations, in which the silica surface not only acts as a support to anchor amines, but also can actively participate in the CO2 capture process through a facile proton transfer reaction with the amine groups.

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Thermodynamic, kinetic and structural investigation of the catalytic role of some protic solvents on the proton transfer reaction in hydantoin: Density functional theory study

Chemical Physics Letters ◽

10.1016/j.cplett.2019.136931 ◽

2020 ◽

Vol 739 ◽

pp. 136931

Author(s):

Zaki S. Safi ◽

Salama Omar ◽

Subhia J. Al Hasanat ◽

Nuha Wazzan ◽

Abdesslem Jedidi

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Structural Investigation ◽

Transfer Reaction ◽

Proton Transfer Reaction ◽

Density Functional Theory Study ◽

Functional Theory ◽

Protic Solvents ◽

Catalytic Role

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Mechanistic investigation of benzene esterification by K2CO3/TiO2: the catalytic role of the multifunctional interface

Chemical Communications ◽

10.1039/d1cc02513a ◽

2021 ◽

Author(s):

Jittima Meeprasert ◽

Guanna Li ◽

Evgeny A Pidko

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Efficient Catalyst ◽

Functional Theory ◽

Mechanistic Investigation ◽

Tio2 Support ◽

Catalytic Role ◽

Catalytic Reactivity

Potassium carbonate dispersed over defective TiO2 support (K2CO3/TiO2) is an efficient catalyst for benzene esterification with CO2 and CH3OH. Density functional theory calculations reveal that this unique catalytic reactivity originates...

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Role of Chemistry and Crystal Structure on the Electronic Defect States in Cs-Based Halide Perovskites

Materials ◽

10.3390/ma14041032 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1032

Author(s):

Anirban Naskar ◽

Rabi Khanal ◽

Samrat Choudhury

Keyword(s):

Crystal Structure ◽

Density Functional ◽

Covalent Bond ◽

Density Functional Theory Calculations ◽

Antisite Defect ◽

Defect States ◽

Functional Theory ◽

Electronic Defect ◽

Constituent Elements

The electronic structure of a series perovskites ABX3 (A = Cs; B = Ca, Sr, and Ba; X = F, Cl, Br, and I) in the presence and absence of antisite defect XB were systematically investigated based on density-functional-theory calculations. Both cubic and orthorhombic perovskites were considered. It was observed that for certain perovskite compositions and crystal structure, presence of antisite point defect leads to the formation of electronic defect state(s) within the band gap. We showed that both the type of electronic defect states and their individual energy level location within the bandgap can be predicted based on easily available intrinsic properties of the constituent elements, such as the bond-dissociation energy of the B–X and X–X bond, the X–X covalent bond length, and the atomic size of halide (X) as well as structural characteristic such as B–X–B bond angle. Overall, this work provides a science-based generic principle to design the electronic states within the band structure in Cs-based perovskites in presence of point defects such as antisite defect.

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DFT Studies of Graphene-Functionalised Derivatives of Capecitabine

Zeitschrift für Naturforschung A ◽

10.1515/zna-2017-0290 ◽

2017 ◽

Vol 72 (12) ◽

pp. 1131-1138 ◽

Cited By ~ 1

Author(s):

Mehdi Aramideh ◽

Mahmoud Mirzaei ◽

Ghadamali Khodarahmi ◽

Oğuz Gülseren

Keyword(s):

Density Functional ◽

Density Functional Theory Calculations ◽

Atomic Scale ◽

Phase System ◽

Molecular Models ◽

Functional Theory ◽

Atomic Properties ◽

Scale Properties ◽

Derivatives Of

AbstractCancer is one of the major problems for so many people around the world; therefore, dedicating efforts to explore efficient therapeutic methodologies is very important for researchers of life sciences. In this case, nanostructures are expected to be carriers of medicinal compounds for targeted drug design and delivery purposes. Within this work, the graphene (Gr)-functionalised derivatives of capecitabine (CAP), as a representative anticancer, have been studied based on density functional theory calculations. Two different sizes of Gr molecular models have been used for the functionalisation of CAP counterparts, CAP-Gr3 and CAP-Gr5, to explore the effects of Gr-functionalisation on the original properties of CAP. All singular and functionalised molecular models have been optimised and the molecular and atomic scale properties have been evaluated for the optimised structures. Higher formation favourability has been obtained for CAP-Gr5 in comparison with CAP-Gr3 and better structural stability has been obtained in the water-solvated system than the isolated gas-phase system for all models. The CAP-Gr5 model could play a better role of electron transferring in comparison with the CAP-Gr3 model. As a concluding remark, the molecular properties of CAP changed from singular to functionalised models whereas the atomic properties remained almost unchanged, which is expected for a carrier not to use significant perturbations to the original properties of the carried counterpart.

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The Role of SiH3 Diffusion in Determining the Surface Smoothness of Plasma-Deposited Amorphous Si Thin Films: An Atomic-Scale Analysis

MRS Proceedings ◽

10.1557/proc-862-a3.2 ◽

2005 ◽

Vol 862 ◽

Author(s):

Mayur S. Valipa ◽

Tamas Bakos ◽

Eray S. Aydil ◽

Dimitrios Maroudas

Keyword(s):

Thin Films ◽

Density Functional ◽

Activation Barrier ◽

Density Functional Theory Calculations ◽

Atomic Scale ◽

Functional Theory ◽

Weak Adsorption ◽

Dynamics Simulations ◽

Hydrogenated Amorphous

AbstractDevice-quality hydrogenated amorphous silicon (a-Si:H) thin films grown under conditions where the SiH3 radical is the dominant deposition precursor are remarkably smooth, as the SiH3 radical is very mobile and fills surface valleys during its diffusion on the a-Si:H surface. In this paper, we analyze atomic-scale mechanisms of SiH3 diffusion on a-Si:H surfaces based on molecular-dynamics simulations of SiH3 radical impingement on surfaces of a-Si:H films. The computed average activation barrier for radical diffusion on a-Si:H is 0.16 eV. This low barrier is due to the weak adsorption of the radical onto the a-Si:H surface and its migration predominantly through overcoordination defects; this is consistent with our density functional theory calculations on crystalline Si surfaces. The diffusing SiH3 radical incorporates preferentially into valleys on the a-Si:H surface when it transfers an H atom and forms a Si-Si backbond, even in the absence of dangling bonds.

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Theoretical Insights into the Role of Water Molecule in The Aqueous/Cu(111) Interface during Corrosion Pathway

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v19i4.275 ◽

2014 ◽

Vol 19 (4) ◽

pp. 235-240

Author(s):

Jun Hu ◽

Xiao-yong Fan ◽

Chao-Ming Wang

Keyword(s):

Water Molecule ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Adsorbed Water ◽

Dipole Interaction ◽

Hydrogen Atoms ◽

Functional Theory ◽

Adsorbed Water Molecule ◽

The One

The absorption and possible reaction paths during corrosion have been systematically identified at the molecular level by us-ing density functional theory calculations. The results show that the co-adsorbed water molecule has a two-fold impact on the corrosive kinetics process. The one is the solvation effect, where water molecule affects the various reactions through ion dipole interaction, without bond fracture and formation. Another is the H-transfer mediator, where the bond of co-adsorbed water molecule breaks and regenerates in order to transfer hydrogen atoms.

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