An ultrafast spectroscopic and quantum mechanical investigation of multiple emissions in push–pull pyridinium derivatives bearing different electron donors

2015 ◽  
Vol 17 (32) ◽  
pp. 20981-20989 ◽  
Author(s):  
B. Carlotti ◽  
E. Benassi ◽  
A. Cesaretti ◽  
C. G. Fortuna ◽  
A. Spalletti ◽  
...  
Keyword(s):  
Density Functional ◽  
Theoretical Study ◽  
Electron Donors ◽  
Quantum Mechanical ◽  
Mechanical Investigation

An interconversion between rotamers in S1 was evidenced for a cationic push–pull pyrenyl derivative through a joint femtosecond fluorescence up-conversion and density functional theoretical study.

Theoretical study of NO3− interacting with carbon nanotube

Open Physics ◽  
2008 ◽  
Vol 6 (1) ◽  
Author(s):  
Silvete Guerini ◽  
David Azevedo ◽  
Maria Lima ◽  
Ivana Zanella ◽  
Josué Filho
Keyword(s):  
Density Functional ◽  
Theoretical Study ◽  
Quantum Mechanical ◽  
Mechanical Interaction ◽  
Electronic Density ◽  
Functional Theory ◽  
Consistent Field ◽  
The Density Functional Theory ◽  
Self Consistent Field ◽  
Field Form

AbstractThis paper deals with quantum mechanical interaction of no 3− with (5,5) and (8,0) swcnts. To perform this we have made an ab initio calculation based on the density functional theory. In these framework the electronic density plays a central role and it was obtained of a self-consistent field form. It was observed through binding energy that NO3− molecule interacts with each nanotube in a physisorption regime. We propose these swcnts as a potential filter device due to reasonable interaction with NO3− molecule. Besides this type of filter could be reusable, therefore after the filtering, the swcnts could be separated from NO3− molecule.

scholarly journals A quantum-mechanical investigation of oxygen vacancies and copper doping in the orthorhombic CaSnO3 perovskite

2018 ◽  
Vol 20 (32) ◽  
pp. 20970-20980 ◽  
Author(s):  
Jefferson Maul ◽  
Iêda Maria Garcia dos Santos ◽  
Julio Ricardo Sambrano ◽  
Silvia Casassa ◽  
Alessandro Erba
Keyword(s):  
Density Functional Theory ◽  
Oxygen Vacancy ◽  
Electronic Properties ◽  
Density Functional ◽  
Oxygen Vacancies ◽  
Quantum Mechanical ◽  
Functional Theory ◽  
Copper Doping ◽  
Oxygen Vacancy Formation ◽  
Mechanical Investigation

In this study we explore the implications of oxygen vacancy formation and of copper doping in the orthorhombic CaSnO3 perovskite, by means of density functional theory, focusing on energetic and electronic properties.

Comparative experimental and theoretical study of the rotational excitation of CO by collision with ortho- and para-D2 molecules

2017 ◽  
Vol 19 (1) ◽  
pp. 189-195 ◽  
Author(s):  
T. Stoecklin ◽  
A. Faure ◽  
P. Jankowski ◽  
S. Chefdeville ◽  
A. Bergeat ◽  
...  
Keyword(s):  
Theoretical Study ◽  
Inelastic Collisions ◽  
Quantum Mechanical ◽  
Rotational Excitation ◽  
Mechanical Investigation

A joint crossed beam and quantum mechanical investigation of the rotationally inelastic collisions of CO with ortho- and para-D2 molecules is reported.

Quantum Mechanical Investigation of Geometrical Structure and Dynamic Behavior of h-BNNT (9,9-5) and h-AlNNT (9,9-5)Single-Walled Nanotubes: NBO Analysis

2019 ◽  
Vol 16 (9) ◽  
pp. 705-717
Author(s):  
Mehrnoosh Khaleghian ◽  
Fatemeh Azarakhshi
Keyword(s):  
Carbon Nanotubes ◽  
Density Functional ◽  
Structural Parameters ◽  
Energy Levels ◽  
Nbo Analysis ◽  
Electronic Energy ◽  
Boron Nitride Nanotubes ◽  
Basis Set ◽  
B3lyp Method ◽  
Mechanical Investigation

In the present research, B45H36N45 Born Nitride (9,9) nanotube (BNNT) and Al45H36N45 Aluminum nitride (9,9) nanotube (AlNNT) have been studied, both having the same length of 5 angstroms. The main reason for choosing boron nitride nanotubes is their interesting properties compared with carbon nanotubes. For example, resistance to oxidation at high temperatures, chemical and thermal stability higher rather than carbon nanotubes and conductivity in these nanotubes, unlike carbon nanotubes, does not depend on the type of nanotube chirality. The method used in this study is the density functional theory (DFT) at Becke3, Lee-Yang-Parr (B3LYP) method and 6-31G* basis set for all the calculations. At first, the samples were simulated and then the optimized structure was obtained using Gaussian 09 software. The structural parameters of each nanotube were determined in 5 layers. Frequency calculations in order to extract the thermodynamic parameters and natural bond orbital (NBO) calculations have been performed to evaluate the electron density and electrostatic environment of different layers, energy levels and related parameters, such as ionization energy and electronic energy, bond gap energy and the share of hybrid orbitals of different layers.

scholarly journals Theoretical Study of Zirconium Isomorphous Substitution into Zeolite Frameworks

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4466
Author(s):  
Duichun Li ◽  
Bin Xing ◽  
Baojun Wang ◽  
Ruifeng Li
Keyword(s):  
Acid Site ◽  
Density Functional ◽  
Theoretical Study ◽  
Atomic Radius ◽  
Acid Sites ◽  
Isomorphous Substitution ◽  
Dispersion Correction ◽  
Brønsted Acidity ◽  
Functional Theory ◽  
Brönsted Acidity

Systematic periodic density functional theory computations including dispersion correction (DFT-D) were carried out to determine the preferred location site of Zr atoms in sodalite (SOD) and CHA-type topology frameworks, including alumino-phosphate-34 (AlPO-34) and silico-alumino-phosphate-34 (SAPO-34), and to determine the relative stability and Brönsted acidity of Zr-substituted forms of SOD, AlPO-34, and SAPO-34. Mono and multiple Zr atom substitutions were considered. The Zr substitution causes obvious structural distortion because of the larger atomic radius of Zr than that of Si, however, Zr-substituted forms of zeolites are found to be more stable than pristine zeolites. Our results demonstrate that in the most stable configurations, the preferred favorable substitutions of Zr in substituted SOD have Zr located at the neighboring sites of the Al-substituted site. However, in the AlPO-34 and SAPO-34 frameworks, the Zr atoms are more easily distributed in a dispersed form, rather than being centralized. Brönsted acidity of substituted zeolites strongly depends on Zr content. For SOD, substitution of Zr atoms reduces Brönsted acidity. However, for Zr-substituted forms of AlPO-34 and SAPO-34, Brönsted acidity of the Zr-O(H)-Al acid sites are, at first, reduced and, then, the presence of Zr atoms substantially increased Brönsted acidity of the Zr-O(H)-Al acid site. The results in the SAPO-34-Zr indicate that more Zr atoms substantially increase Brönsted acidity of the Si-O(H)-Al acid site. It is suggested that substituted heteroatoms play an important role in regulating and controlling structural stability and Brönsted acidity of zeolites.

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