Substituent Effects in 3,3’ Bipyrazole Derivatives. X-ray Crystal Structures, Molecular Properties and DFT Analysis

The single crystal X-ray structure of new 1,1’-bis(2-nitrophenyl)-5,5’-diisopropyl-3,3’-bipyrazole, 1, is triclinic P I–, a = 7.7113(8), b = 12.3926(14), c = 12.9886(12) Å, α = 92.008(8), β = 102.251(8), γ = 99.655(9)°. The structural arrangement is compared to that of 5,5’-diisopropyl-3,3’-bipyrazole, 5, whose single crystal structure is found tetragonal I41/a, a = b = 11.684(1), c = 19.158(1) Å. The comparison is also extended to the structures previously determined for 1,1’-bis(2-nitrophenyl)-5,5’-propyl-3,3’-bipyrazole, 2, 1,1’-bis(4-nitrophenyl)-5,5’-diisopropyl-3,3’-bipyrazole, 3, and 1,1’-bis(benzyl)-5,5’-diisopropyl-3,3’-bipyrazole, 4. Density Functional Theory (DFT) calculations are used to investigate the molecular geometries and to determine the global reactivity parameters. The geometry of isolated molecules and the molecular arrangements in the solid state are analyzed according to the nature of the groups connected to the bipyrazole core.

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XRD Multi-Temperatures Study of N,N'-bis(2-Hydroxyethyl)Benzene-1,4-Dicarboxamide

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.163.256 ◽

2010 ◽

Vol 163 ◽

pp. 256-259

Author(s):

Gabriela Bednarek ◽

Maria Nowak ◽

Joachim Kusz ◽

Jerzy Ossowski

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Dft Calculations ◽

Chemical Reactions ◽

Title Compound ◽

Density Functional ◽

Temperature Analysis ◽

Functional Theory ◽

X Ray ◽

The Stability

N,N’ – bis – (2– hydroxy – ethylene) – terephthalamide (BHETA) has been obtained by aminolysis of polyethylene terephthalate (PET) using excess of monoethanoloamine and it has been physicochemically characterized [1]. In this paper there are shown the results of the multi-temperature X-ray measurement which were performed to provide information about the stability of the structure. Detailed temperature analysis of the crystal structure allows us to determine properties of the compound which is very important product of recycling PET wastes in order to use it for further chemical reactions. The structure of the title compound was also modelled by density functional theory (DFT) calculations.

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

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s205327331408557x ◽

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.

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Syntheses, crystal structures and density functional theory investigations of copper(ii) complexes bearing tridentate Schiff base ligands derived from 8-aminoquinoline

CrystEngComm ◽

10.1039/c5ce00809c ◽

2015 ◽

Vol 17 (30) ◽

pp. 5664-5671 ◽

Cited By ~ 10

Author(s):

Prasanta Kumar Bhaumik ◽

Antonio Bauzá ◽

Michael G. B. Drew ◽

Antonio Frontera ◽

Shouvik Chattopadhyay

Keyword(s):

Density Functional Theory ◽

Schiff Base ◽

Solid State ◽

Dft Calculations ◽

Crystal Structures ◽

Density Functional ◽

Schiff Base Complexes ◽

Schiff Base Ligands ◽

Functional Theory ◽

Tridentate Schiff Base

Three copper(ii) Schiff base complexes have been synthesized and characterized. Supramolecular assemblies in the solid state are analyzed by DFT calculations.

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Synthesis Single Crystal X-ray Structure DFT Studies and Hirshfeld Analysis of New Benzylsulfanyl-Triazolyl-Indole Scaffold

Crystals ◽

10.3390/cryst10080685 ◽

2020 ◽

Vol 10 (8) ◽

pp. 685 ◽

Cited By ~ 2

Author(s):

Ahmed T. A. Boraei ◽

Saied M. Soliman ◽

Sammer Yousuf ◽

Assem Barakat

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Single Crystal ◽

13C Nmr ◽

Density Functional ◽

Chemical Shifts ◽

Functional Theory ◽

X Ray ◽

Reactivity Descriptors ◽

Hirshfeld Analysis

Benzylsulfanyl-triazolyl-indole scaffold was synthesized through coupling of 4-amino-5-(1H-indol-2-yl)-1,2,4-triazol-3(2H)-thione and benzyl bromide in EtOH under basic conditions (K2CO3). The benzylation direction was deduced from the 13C NMR signal found at 35.09 ppm, assigned for the methylene carbon of the benzyl group, this value indicates that the benzyl group attacks sulfur, not nitrogen. 1H NMR, 13C NMR, COSY, HMQC, HRMS and X-ray single crystal diffraction analysis were used for structure assignment. The desired compound accomplished in good yield. Hirshfeld analysis revealed the importance of the short N...H (1.994–2.595 Ǻ), S…H (2.282 Ǻ) and C…H (2.670 Ǻ) contacts as well as the weak π-π stacking interactions in the molecular packing of benzylthio-triazolyl-indole scaffold. Its electronic and structural aspects were predicted using density functional theory (DFT) calculations and the reactivity descriptors as well. The Uv-Vis spectral bands were assigned based on the time-dependant density functional theory TD-DFT calculations, while the gauge-including atomic orbitals (GIAO) method was used to predict the 1H and 13C NMR chemical shifts.

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Structure and New Substructure of α-Ti2O3: X-ray Diffraction and Theoretical Study

Journal of Modern Materials ◽

10.21467/jmm.8.1.3-11 ◽

2021 ◽

Vol 8 (1) ◽

pp. 3-11

Author(s):

Soumia Merazka ◽

Lamia Hammoudi ◽

Mohammed Kars ◽

Mohamed Sidoumou ◽

Thierry Roisnel

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Dft Calculations ◽

Relative Stability ◽

Density Functional ◽

Theoretical Study ◽

X Ray Diffraction ◽

Functional Theory ◽

X Ray ◽

High Coordination

The Crystal structure of both α-Ti2O3 and its new substructure with a halved c-axis has been investigated by single-crystal X-ray diffraction and density functional theory (DFT) calculations. The α-Ti2O3 substructure described in the R-3m space group, reveals an unusual 12-fold high coordination of Ti atoms forming edge and face-sharing distorted hexagonal prisms TiO12 stacking along the c-axis. The Hubbard-corrections predict a close bandgap for both α-Ti2O3 and its substructure; whereas a comparative study of their relative stability indicates that the substructure is thermodynamically less stable.

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Synthesis and properties of tetracyanoquinodimethane derivatives

Heterocyclic Communications ◽

10.1515/hc-2018-0136 ◽

2018 ◽

Vol 24 (5) ◽

pp. 249-254 ◽

Cited By ~ 1

Author(s):

Lei Zhu ◽

Haizhen Chang ◽

Christopher L. Vavallo ◽

Jianhui Jiang ◽

Zebing Zeng ◽

...

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Single Crystal ◽

Organic Semiconductor ◽

Density Functional ◽

Semiconductor Materials ◽

X Ray Diffraction ◽

Functional Theory ◽

X Ray ◽

Organic Semiconductor Materials

Abstract Two new aza-acenequinone derivatives 4 and 5 were prepared by cyclocondensation of diamines 2 and 3 with bis(triisopropylsilyl)-dialkynyl-l,2-dione 1. Further reactions of compounds 4 and 5 with malononitrile using the Lehnert reagent afforded corresponding tetracyanoquinodimethane (TCNQ) derivatives 6 and 7. Compounds 4, 6 and 7 were characterized by single crystal X-ray diffraction techniques. Compounds 6 and 7 were studied electrochemically and photochemically. Density functional theory (DFT) calculations on compounds 6 and 7 indicate that both compounds have the potential to be candidates for organic semiconductor materials.

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Polymorphs of Rb3ScF6: X-ray and Neutron Diffraction, Solid-State NMR, and Density Functional Theory Calculations Study

Inorganic Chemistry ◽

10.1021/acs.inorgchem.1c00485 ◽

2021 ◽

Vol 60 (8) ◽

pp. 6016-6026

Author(s):

Aydar Rakhmatullin ◽

Maxim S. Molokeev ◽

Graham King ◽

Ilya B. Polovov ◽

Konstantin V. Maksimtsev ◽

...

Keyword(s):

Density Functional Theory ◽

Solid State ◽

Neutron Diffraction ◽

Solid State Nmr ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

X Ray

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Iron(II) complexes of dimethyltriazacyclophane

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229618015255 ◽

2018 ◽

Vol 74 (12) ◽

pp. 1641-1649

Author(s):

Wei-Tsung Lee ◽

Matthias Zeller ◽

David Upp ◽

Yuliya Politanska ◽

Doug Steinman ◽

...

Keyword(s):

Density Functional Theory ◽

Solid State ◽

Dft Calculations ◽

Density Functional Calculations ◽

Density Functional ◽

Coordination Mode ◽

Functional Theory ◽

Metal Centers ◽

Bonding Interaction

Treatment of the ortho-triazacyclophane 1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-triene [(C6H5)3(NH)(NCH3)2, L1] with Fe[N(SiMe3)2]2 yields the dimeric iron(II) complex bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)bis[(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)iron(II)], [Fe(C20H18N3)4] or Fe2(L1)4 (9). Dissolution of 9 in tetrahydrofuran (THF) results in solvation by two THF ligands and the formation of a simpler monoiron complex, namely bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido-κN 7)bis(tetrahydrofuran-κO)iron(II), [Fe(C20H18N3)2(C4H8O)2] or (L1)2Fe(THF)2 (10). The reaction is reversible and 10 reverts in vacuo to diiron complex 9. In the structures of both 9 and 10, the monoanionic triazacyclophane ligand L1− is observed in only the less-symmetric saddle conformation. No bowl-shaped crown conformers are observed in the solid state, thus preventing chelating κ3-coordination to the metal as had been proposed earlier based on density functional theory (DFT) calculations. Instead, the L1− ligands are bound in either a η2-chelating fashion through the amide and one amine donor (for one of the four ligands of 9), or solely through their amide N atoms in an even simpler monodentate η1-coordination mode. Density functional calculations on dimer 9 revealed nearly full cationic charges on each Fe atom and no bonding interaction between the two metal centers, consistent with the relatively long Fe...Fe distance of 2.912 (1) Å observed in the solid state.

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