scholarly journals Crystal Structure Determination of 4-[(Di-p-tolyl-amino)-benzylidene]-(5-pyridin-4-yl-[1,3,4]thiadiazol-2-yl)-imine along with Selected Properties of Imine in Neutral and Protonated Form with Camforosulphonic Acid: Theoretical and Experimental Studies

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1952
Author(s):  
Agnieszka Dylong ◽  
Karolina Dysz ◽  
Krzysztof A. Bogdanowicz ◽  
Wojciech Przybył ◽  
Krzysztof A. Konieczny ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Density Functional ◽  
Experimental Studies ◽  
Protonated Form ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Thermographic Camera

The crystal structure was determined for the first time for 4-[(di-p-tolyl-amino)benzylidene]-(5-pyridin-4-yl-[1,3,4]thiadiazol-2-yl)-imine (trans-PPL9) by X-ray diffraction. The imine crystallized in the monoclinic P21/n space group with a = 18.9567(7) Å, b = 6.18597(17) Å, c = 22.5897(7) Å, and β = 114.009(4)°. Intermolecular interactions in the PPL9 crystal were only weak C−H∙∙∙N hydrogen bonds investigated using the Hirshfeld surface. The electronic and geometric structure of the imine were investigated by the density functional theory and the time-dependent density-functional theory. The properties of the imine in neutral and protonated form with camforosulphonic acid (CSA) were investigated using cyclic voltammetry, UV–vis and 1H NMR spectroscopy. Theoretical and experimental studies showed that for the 1:1 molar ratio the protonation occured on nitrogen in pyridine in the PPL9 structure, as an effect of Brönsted acid–base interactions. Thermographic camera was used to defined defects in constructed simple devices with ITO/PPL9 (or PPL9:CSA)/Ag/ITO architecture. In conclusion, a thermally stable imine was synthesized in crystalline form and by CSA doping, a modification of absorption spectra together with reduction of overheating process was observed, suggesting its potential application in optoelectronics.

Density-functional-theory-predicted symmetry lowering from cubic to tetragonal in nickel hexacyanoferrate

2020 ◽  
Vol 53 (1) ◽  
pp. 117-126 ◽  
Author(s):  
Seyedayat Ghazisaeed ◽  
Md Minuddin ◽  
Heinz Nakotte ◽  
Boris Kiefer
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Density Functional ◽  
Magnetic Measurements ◽  
Hydration Shell ◽  
Strong Support ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
Nickel Hexacyanoferrate ◽  
Nickel Cation

Density-functional-theory (DFT) computations on a Prussian blue analogue (PBA), nickel hexacyanoferrate, Ni2+ 3[Fe3+(CN)6]2·nH2O, predict the existence of a tetragonal (P 4 m2) crystal structure that is energetically degenerate with the previously reported cubic (F 43m) structure for this PBA. The proposed tetragonal structure satisfies observations, such as X-ray diffraction and magnetic measurements, that have been reported previously. A van der Waals corrected exchange-correlation functional is used in the DFT+U computations for an improved description of hydrogen bonding. The results provide strong support for a revised and simplified crystallographic description of Ni2+ 3[Fe3+(CN)6]2·nH2O, and show how H2O molecules stabilize the crystal structure and affect its magnetic and electronic properties. The symmetry lowering in nickel hexacyanoferrate is attributed to the hydration shell of the interstitial nickel cation. Calculations strongly suggest a maximum of n = 7 interstitial H2O molecules per formula unit for nickel hexacyanoferrate at room temperature, and a higher water content at temperatures below T ≃ 200 K. Since the symmetry lowering relies on the presence of interstitial H2O molecules, this revised crystallographic description may be applicable more generally to the large class of F 43m-structured PBAs.

Synthesis of [Re2Cl4(O)2(µ-O)(3,5-lut)4] and investigation of its structure via X-ray and spectroscopic measurements and DFT calculations

2014 ◽  
Vol 68 (5) ◽  
Author(s):  
Sławomir Michalik ◽  
Jan Małecki ◽  
Natalia Młynarczyk
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Computational Study ◽  
Dft Method ◽  
Time Dependent ◽  
Electronic Transitions ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
The Density Functional Theory

AbstractA combined experimental and computational study of the dinuclear rhenium(V) complex containing (ReO)2(µ-O) core is presented in this article. The solid-state [Re2Cl4(O)2(µ-O)(3,5-lut)4] (3,5-lut = 3,5-dimethylpyridine) complex was characterised structurally (by single crystal X-ray diffraction) and spectroscopically (by IR, NMR, UV-VIS). The electronic structure was examined using the density functional theory (DFT) method. The spin-allowed electronic transitions were calculated using the time-dependent DFT method, and the UV-VIS spectrum was discussed.

scholarly journals Selective CO2 Sorption Using a Compartmentalized Coordination Polymer with Discrete Voids

2020 ◽  
Author(s):  
Eugenia Miguel-Casañ ◽  
Eduardo Andres-Garcia ◽  
Joaquin Calbo ◽  
Dr. Mónica Giménez Marqués ◽  
Guillermo Minguez Espallargas
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Coordination Polymer ◽  
Adsorption Isotherms ◽  
Density Functional ◽  
Loading Capacity ◽  
Functional Theory ◽  
Co2 Sorption ◽  
The Density Functional Theory ◽  
Gas Molecules

We report a novel Fe(II) compartmentalized coordination polymer (CCP) capable of physisorbing gas molecules in a selective manner. The crystal structure was modelled theoretically under the Density Functional Theory revealing the presence of discrete voids of 380 Å3, significantly larger than those reported for its predecesors. Adsorption isotherms of pure N2, CH4 and CO2 were measured, obtaining a loading capacity of 0.6, 1.7 and 2.2 molecules/void at 10 bar and at 298 K. Dynamic breakthrough gas experiments have been performed at different fluxes and temperatures, showing efficient adsorption and excellent selectivities for CO2 in gas mixtures with methane and nitrogen.

scholarly journals Ab initio and DFT study on Cu (II) complex salicylate derivative

2014 ◽  
Vol 70 (a1) ◽  
pp. C1442-C1442
Author(s):  
Karthikeyan Natarajan ◽  
Sathya Duraisamy ◽  
Sivakumar Kandasamy
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Single Crystal ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Density Functional ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray

X -ray diffraction becomes a routine process these decades for determining crystal structure of the materials. Most of the crystal structures solved nowadays is based on single crystal X-ray diffraction because it solves the crystal and molecular structures from small molecules to macro molecules without much human intervention. However it is difficult to grow single crystals of sufficient size and quality for conventional single-crystal X-ray diffraction studies. In such cases it becomes essential that structural information can be determined from powder diffraction data. With the recent developments in the direct-space approaches for structure solution, ab initio crystal structure analysis of molecular solids can be accomplished from X-ray powder diffraction data. It should be recalled that crystal structure determination from laboratory X-ray powder diffraction data is a far more difficult task than that of its single-crystal counterpart, particularly when the molecule possesses considerable flexibility or there are multiple molecules in the asymmetric unit. Salicylic acid and its derivatives used as an anti-inflammatory drug are known for its numerous medicinal applications. In our study, we synthesized mononuclear copper (II) complex of salicylate derivative. The structural characterization of the prepared compound was carried out using powder X-ray diffraction studies. Crystal structure of the compound has been solved by direct-space approach and refined by a combination of Rietveld method using TOPAS Academic V4.1. Density Functional Theory (DFT) calculations have to be carried in the solid state for the compound using GaussianW9.0 in the frame work of a generalized-gradient approximation (GGA). The geometry optimization was to be performed using B3LYP density functional theory. The atomic coordinates were taken from the final X-ray refinement cycle.

Crystal Structure, Optical Properties of Molecular Crystals 1, 3-propanediol Bis(4-aminobenzoate)

2014 ◽  
Vol 1052 ◽  
pp. 207-211
Author(s):  
Rui Ting Xue ◽  
Wei Song Sun ◽  
Si Rong Yu
Keyword(s):  
Crystal Structure ◽  
Optical Properties ◽  
Density Functional ◽  
Molecular Crystals ◽  
Density Functional Theory Method ◽  
Theory Method ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
The Density Functional Theory

The crystal structure of 1, 3-propanediol bis (4-aminobenzoate) has been determined by single crystal X-ray diffraction. The UV-vis spectra have been characterized experimentally. The nonlinear optical properties were investigated with the density functional theory method. The calculated first hyperpolarizability values are 7.69×10-30, 14.22×10-30 and 26.66×10-30 esu for the monomer, dimmer and trimer structure of the compound. The results show that the compound has high hyperpolarizability and the hyperpolarizability multipled along with the increasing number of the molecules.

The Crystal Structure of Dibromonitrotoluen (DBNT) C7Br2H5 NO2

2011 ◽  
Vol 324 ◽  
pp. 209-212
Author(s):  
Mohamed Larbi Medjroubi ◽  
Ouarda Brihi ◽  
Noudjoud Hamdouni ◽  
Ali Boudjada ◽  
Jean Meinnel
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Molecular Conformation ◽  
Dynamic Properties ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Calculation Results ◽  
Experimental Spectroscopy ◽  
Good Probe

The crystal structure of Dibromonitrotoluen (DBNT) obtained at the ambient temperature 293k from the X-ray diffraction crystallizes in the space group P-1 with 2 molecules by mesh. The crystal growth is made along the a axis. In parallel with this study, a theoretical calculation of molecular conformation from the density functional theory (DFT) carried out using the Gaussian03 chain program in the case of isolated molecule, led to results of Optimization very close to the experiment. The molecular conformation calculations were made from two different functional the B3LYP and MPW1PW91. The values of bond lengths obtained from the functional MPW1PW91 and base set 6-311G are very close to the experiment with a gap of 1.25% (2.14% for the B3LYP) while for bond angles, calculation results are better for functional B3LYP (Lan2DZ) 0.95% and 1.02% for MPW1PW91.In this work a study of internal modes of Dibromonitrotoluen (DBNT) is presented, while comparing the infrared spectroscopic experimental results and the DFT studies of the isolated molecule. This material is a good probe to test the model precision and the calculated methods used to interpret dynamic properties by experimental spectroscopy.

scholarly journals Selective CO2 Sorption Using a Compartmentalized Coordination Polymer with Discrete Voids

2020 ◽  
Author(s):  
Eugenia Miguel-Casañ ◽  
Eduardo Andres-Garcia ◽  
Joaquin Calbo ◽  
Dr. Mónica Giménez Marqués ◽  
Guillermo Minguez Espallargas
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Coordination Polymer ◽  
Adsorption Isotherms ◽  
Density Functional ◽  
Loading Capacity ◽  
Functional Theory ◽  
Co2 Sorption ◽  
The Density Functional Theory ◽  
Gas Molecules

We report a novel Fe(II) compartmentalized coordination polymer (CCP) capable of physisorbing gas molecules in a selective manner. The crystal structure was modelled theoretically under the Density Functional Theory revealing the presence of discrete voids of 380 Å3, significantly larger than those reported for its predecesors. Adsorption isotherms of pure N2, CH4 and CO2 were measured, obtaining a loading capacity of 0.6, 1.7 and 2.2 molecules/void at 10 bar and at 298 K. Dynamic breakthrough gas experiments have been performed at different fluxes and temperatures, showing efficient adsorption and excellent selectivities for CO2 in gas mixtures with methane and nitrogen.

The hydrolysis mechanism of polyglycolic acid under tensile mechanical loading: a density functional theory study

RSC Advances ◽  
2014 ◽  
Vol 4 (68) ◽  
pp. 35862-35867 ◽  
Author(s):  
Shin-Pon Ju ◽  
Wei-Chun Huang ◽  
Chien-Chia Chen
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Mechanical Loading ◽  
Density Functional ◽  
Experimental Studies ◽  
Polyglycolic Acid ◽  
Density Functional Theory Study ◽  
Functional Theory ◽  
Hydrolysis Mechanism ◽  
The Density Functional Theory

The hydrolysis mechanisms of polyglycolic acid (PGA) under tensile mechanical loading were studied by the density functional theory (DFT) calculations for illustrating the enhancement of PGA hydrolysis by external mechanical loading found in previous experimental studies (Iran. Polym. J., 2008, 17(9), 691–701).

A revisit to the structure of Au20(SCH2CH2Ph)16: a cubic nanocrystal-like gold kernel

Nanoscale ◽  
2018 ◽  
Vol 10 (22) ◽  
pp. 10357-10364 ◽  
Author(s):  
Pu Wang ◽  
Xiangxiang Sun ◽  
Xia Liu ◽  
Lin Xiong ◽  
Zhongyun Ma ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional Theory ◽  
Dft Calculations ◽  
Density Functional ◽  
Structural Form ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Total Energies

A new stable structural form of Au20(SR)16 cluster is theoretically predicted. The density functional theory (DFT) calculations with the inclusion of dispersion corrections indicated the nanocrystal-like isomer (Au20-Iso1) has comparable and even lower total energies compared to the non-fcc crystal structure of Au20(SPh-tBu)16.

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