scholarly journals New Pair of 2-Amino-naphthoxazoles Derived from β-Lapachone: Synthesis, Spectral Evaluation and Crystal Structure

2021 ◽  
Author(s):  
Leonardo Silva ◽  
Emanoel Hottes ◽  
Ari da Silva ◽  
Luan Freire ◽  
Guilherme Guedes ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Condensation Reaction ◽  
Correlation Coefficients ◽  
Basic Medium ◽  
Synthetic Approach ◽  
Spectroscopic Techniques ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
Spectral Evaluation

This work describes a novel synthetic route for obtaining 2-amino-naphthoxazoles derived from β-lapachone, which consists of a condensation reaction between β-lapachone and thiourea in a basic medium. This synthetic approach can be seen as a potential route for obtaining 2-amino-oxazoles from quinones. The obtained amino-naphthoxazoles were characterized by spectroscopic techniques and the crystal structure of one of them was resolved by X-ray diffraction. The experimental results were compared to that obtained through density functional theory (DFT) calculations, revealing high correlation coefficients.

On tungstates of divalent cations (III) – Pb5O2[WO6]

2020 ◽  
Vol 235 (8-9) ◽  
pp. 311-317
Author(s):  
Stephan G. Jantz ◽  
Florian Pielnhofer ◽  
Henning A. Höppe
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Quantum Chemical ◽  
Density Functional ◽  
Divalent Cations ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
First Results ◽  
Electrostatic Calculations

Abstract${\text{Pb}}_{5}{\text{O}}_{2}\left[{\text{WO}}_{6}\right]$ was discovered as a frequently observed side phase during our investigation on lead tungstates. Its crystal structure was solved by single-crystal X-ray diffraction ($P{2}_{1}/n$, $a=7.4379\left(2\right)$ Å, $b=12.1115\left(4\right)$ Å, $c=10.6171\left(3\right)$ Å, $\beta =90.6847\left(8\right)$°, $Z=4$, ${R}_{\text{int}}=0.038$, ${R}_{1}=0.020$, $\omega {R}_{2}=0.029$, 4188 data, 128 param.) and is isotypic with ${\text{Pb}}_{5}{\text{O}}_{2}\left[{\text{Te}}_{6}\right]$. ${\text{Pb}}_{5}{\text{O}}_{2}\left[{\text{WO}}_{6}\right]$ comprises a layered structure built up by non-condensed [WO6]${}^{6-}$ octahedra and ${\left[{\text{O}}_{4}{\text{Pb}}_{10}\right]}^{12+}$ oligomers. The compound was characterised by spectroscopic measurements (Infrared (IR), Raman and Ultraviolet–visible (UV/Vis) spectra) as well as quantum chemical and electrostatic calculations (density functional theory (DFT), MAPLE) yielding a band gap of 2.9 eV fitting well with the optical one of 2.8 eV. An estimation of the refractive index based on the Gladstone-Dale relationship yielded $n\approx 2.31$. Furthermore first results of the thermal analysis are presented.

A mononuclear cobalt(III) 3-(2-pyridyl)-5-phenyl-1,2,4-triazolato complex: hydrothermal synthesis, crystal structure, thermostability, and DFT calculations

2015 ◽  
Vol 70 (9) ◽  
pp. 631-636 ◽  
Author(s):  
Huaixian Liu ◽  
Lin Sun ◽  
Huiliang Zhou ◽  
Peipei Cen ◽  
Xiaoyong Jin ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Free Ligand ◽  
Supramolecular Network ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Functional Theory ◽  
X Ray ◽  
Mononuclear Cobalt

AbstractStarting with 1H-3-phenyl-5-(pyridin-2-yl)-1,2,4-triazole (1-Hppt), a Co(III) complex, [Co(ppt)3] (1), has been synthesized by reaction with CoF3 under hydrothermal conditions and characterized by its infrared spectrum and elemental analysis. The structure was determined by single-crystal and powder X-ray diffraction. Density functional theory (DFT) was employed to determine the optimized geometry and preferred conformation of the free ligand. A supramolecular network is formed via π–π stacking interactions. The conformation and geometry of the ligands correspond with the calculated results.

scholarly journals Crystal structure and DFT study of (E)-N-[2-(1H-indol-3-yl)ethyl]-1-(anthracen-9-yl)methanimine

2017 ◽  
Vol 73 (9) ◽  
pp. 1329-1332
Author(s):  
Md. Serajul Haque Faizi ◽  
Necmi Dege ◽  
Sergey Malinkin ◽  
Tetyana Yu. Sliva
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Density Functional ◽  
Condensation Reaction ◽  
Ring System ◽  
Two Dimensional ◽  
Indole Ring ◽  
Functional Theory ◽  
Compound C ◽  
The Density Functional Theory

The title compound, C25H20N2, (I), was synthesized from the condensation reaction of anthracene-9-carbaldehyde and tryptamine in dry ethanol. The indole ring system (r.m.s. deviation = 0.016 Å) makes a dihedral angle of 63.56 (8)° with the anthracene ring (r.m.s. deviation = 0.023 Å). There is a short intramolecular C—H...N interaction present, and a C—H...π interaction involving the two ring systems. In the crystal, the indole H atom forms an intermolecular N—H...π interaction, linking molecules to form chains along theb-axis direction. There are also C—H...π interactions present, involving the central and terminal rings of the anthracene unit, linking the chains to form an overall two-dimensional layered structure, with the layers parallel to thebcplane. The density functional theory (DFT) optimized structure, at the B3LYP/6-311 G(d,p) level, is compared with the experimentally determined molecular structure in the solid state.

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.

scholarly journals Crystal structure and DFT study of (E)-2,6-di-tert-butyl-4-{[2-(pyridin-2-yl)hydrazin-1-ylidene)methyl}phenol

2017 ◽  
Vol 73 (10) ◽  
pp. 1449-1452
Author(s):  
Md. Serajul Haque Faizi ◽  
Ashanul Haque ◽  
Mustafa Dege ◽  
Necmi Dege ◽  
Maria L. Malysheva
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Density Functional Theory ◽  
Hydrogen Bond ◽  
Density Functional ◽  
Condensation Reaction ◽  
Monoclinic Space Group ◽  
Functional Theory ◽  
Compound C ◽  
Ring Motif

The title compound, C20H27N3O, was synthesized by condensation reaction of 3,5-di-tert-butyl-4-hydroxybenzaldehyde and 2-hydrazinylpyridine, and crystallizes in the centrosymmetric monoclinic space groupC2/c. The conformation about the C=N bond isE. The dihedral angle between the rings is 18.1 (3)°. An intermolecular N—H...N hydrogen bond generates anR22(8) ring motif. In the crystal, N—H...N hydrogen bonds connect pairs of molecules, forming dimers. Density functional theory (DFT) optimized structures at the B3LYP/6–311 G(d,p) level are compared with the experimentally determined molecular structure in the solid state.

The crystal structure of Zr2NiD4.5

2006 ◽  
Vol 62 (6) ◽  
pp. 972-978 ◽  
Author(s):  
M. H. Sørby ◽  
A. E. Gunnæs ◽  
O. M. Løvvik ◽  
H. W. Brinks ◽  
H. Fjellvåg ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Neutron Diffraction Data ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
X Ray ◽  
Tetrahedral Sites ◽  
Powder Neutron Diffraction ◽  
Powder Neutron Diffraction Data

The crystal structure of Zr2NiD4.5 has been determined by a combination of synchrotron radiation powder X-ray diffraction, electron diffraction and powder neutron diffraction data. Deuterium ordering results in a triclinic supercell given by a super = 6.81560 (7), b super = 8.85137 (9), c super = 8.88007 (10) Å, αsuper = 79.8337 (8), βsuper = 90.0987 (9), γsuper = 90.3634 (9)°, which relates to the non-super unit cell as a super = −a, b super = −b − c, c super = −b + c. The centrosymmetric and fully ordered deuterium sublattice was determined by simulated annealing and Rietveld refinement. Deuterium was found to occupy three types of tetrahedral sites: two that are coordinated by four Zr atoms and one that is coordinated by three Zr atoms and one Ni atom. All D—D distances are longer than 2 Å. The feasibility of the crystal structure was supported by density functional theory calculations.

Powder X-ray diffraction of pazopanib hydrochloride Form 1, C21H24N7O2SCl

2021 ◽  
pp. 1-3
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Powder Diffraction ◽  
Density Functional ◽  
Lattice Energy ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Powder Diffraction File ◽  
Functional Theory ◽  
X Ray

The crystal structure of pazopanib hydrochloride Form 1 has been refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Pazopanib hydrochloride crystallizes in space group P-1 (#2) with a = 8.45008(6), b = 8.71310(12), c = 16.05489(35) Å, α = 79.5996(9), β = 86.4784(5), γ = 87.3764(3)°, V = 1159.724(9) Å3, and Z = 2. The crystal structure is essentially identical to that of CSD Refcode CEVYEK. There are four strong N–H⋯Cl hydrogen bonds to the chloride anion. Several additional weaker N–H⋯Cl and C–H⋯Cl hydrogen bonds are also present. A variety of C–H⋯O, C–H⋯N, and N–H⋯S hydrogen bonds also contribute to the lattice energy. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.

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.

Crystal Structure of Cs2Zn(NO2)4: Influence of Steric Crowding on Nitrite Coordination

2005 ◽  
Vol 58 (3) ◽  
pp. 224 ◽  
Author(s):  
Susan G. Oates ◽  
Michael A. Hitchman ◽  
Brian W. Skelton ◽  
Robert Stranger ◽  
Horst Stratemeier ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Density Functional ◽  
Density Functional Theory Calculations ◽  
Energy Curve ◽  
X Ray Diffraction ◽  
Nitrite Ion ◽  
Ligand Interaction ◽  
Functional Theory ◽  
X Ray ◽  
Steric Crowding

The crystal structure of Cs2[Zn(NO2)4] has been determined by X-ray diffraction. Each nitrite ion in the Zn(NO2)42− group forms one short [2.080(3) Å] and one long [2.516(3) Å] Zn–O bond, the metal–ligand interaction being intermediate between symmetrical chelation and syn-unidentate nitrito coordination. It seems likely that this unsymmetrical geometry is adopted in order to minimize ligand–ligand repulsions, though density functional theory calculations suggest a very shallow potential energy curve for the complex.

Sign in / Sign up

Export Citation Format

Share Document