scholarly journals Synthesis, X-ray Structure, Conformational Analysis, and DFT Studies of a Giant s-Triazine bis-Schiff Base

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1418
Author(s):  
Zainab M. Almarhoon ◽  
Maha I. Al-Zaben ◽  
Abir Ben Bacha ◽  
Matti Haukka ◽  
Ayman El-Faham ◽  
...  
Keyword(s):  
Conformational Analysis ◽  
Unit Cell ◽  
Dft Studies ◽  
Orthorhombic Crystal ◽  
Stable Conformer ◽  
Cell Parameters ◽  
Crystal Stability ◽  
Crystal Unit Cell ◽  
Intermolecular Contacts ◽  
The One

The current work involves the synthesis of 2,2′-(6-(piperidin-1-yl)-1,3,5-triazine-2,4-diyl)bis(hydrazin-2-yl-1-ylidene))bis(methanylylidene))diphenol 4, characterization, and the DFT studies of the reported compound. The crystal unit cell parameters of 4 are a = 8.1139(2) Å, b = 11.2637(2) Å, c = 45.7836(8) Å. The unit cell volume is 4184.28(15) Å3 and Z = 4. It crystallized in the orthorhombic crystal system and Pbca space group. The O…H, N…H, C…H, H…H and C…C intermolecular contacts which affect the crystal stability were quantitatively analyzed using Hirshfeld calculations. Their percentages were calculated to be 9.8, 15.8, 23.7, 46.4, and 1.6% from the whole contacts occurred in the crystal, respectively. Conformational analysis was performed using DFT calculations for 17 suggested conformers and the most stable conformer was found to be the one which is stabilized by two intramolecular O-H…N hydrogen bonding interactions. This conclusion was further revealed by natural bond orbital calculations.

X-ray powder diffraction analysis of imipenem monohydrate

2012 ◽  
Vol 27 (1) ◽  
pp. 20-24
Author(s):  
F. Needham ◽  
C. E. Crowder ◽  
J. W. Reid ◽  
T. G. Fawcett ◽  
J. Faber
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Orthorhombic Crystal ◽  
X Ray ◽  
Cell Parameters ◽  
Pharmaceutical Agent ◽  
Structural Database

An experimental X-ray powder diffraction pattern was produced and analyzed for imipenem monohydrate, an antimicrobial pharmaceutical agent. Although there are no experimental powder patterns in the ICDD PDF-4/Organics Database, there is one powder pattern calculated with single-crystal X-ray diffraction data from the Cambridge Structural Database. Here, we report the refined experimental powder diffraction data for imipenem monohydrate. These data for imipenem monohydrate are consistent with an orthorhombic crystal system having reduced unit-cell parameters of a = 8.2534(3) Å, b = 11.1293(4) Å, and c = 15.4609(6) Å. The resulting unit-cell volume, 1420.15(15) Å3, indicates four formula units per unit cell. Observed peaks are consistent with the P212121 space group.

scholarly journals Synthesis of Enaminones-Based Benzo[d]imidazole Scaffold: Characterization and Molecular Insight Structure

Crystals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 955
Author(s):  
Saeed Alshahrani ◽  
Saied M. Soliman ◽  
Abdullah Saleh Alamary ◽  
Abdullah Mohammed Al-Majid ◽  
Matti Haukka ◽  
...  
Keyword(s):  
Unit Cell ◽  
Imidazole Derivative ◽  
Monoclinic Space Group ◽  
Asymmetric Unit ◽  
Unit Cell Parameters ◽  
Orthorhombic Crystal ◽  
One Pot ◽  
Dimethylformamide Dimethylacetal ◽  
Space Group ◽  
Cell Parameters

(E)-1-(1H-Benzo[d]imidazol-2-yl)-3-(dimethylamino)prop-2-en-1-one 2 was synthesized by one-pot synthesis protocol of 2-acetyl benzo[d]imidazole with dimethylformamide dimethylacetal (DMF-DMA) in xylene at 140 °C for 8 h. Reaction of enaminone derivative 1 with acetylacetone in the presence of AcOH/NH4OAc under reflux afforded the cyclized pyridino-benzo[d]imidazole derivative 3. The latter compound was converted into the corresponding β-enaminone 4 with DMF-DMA. The single crystal X-ray diffraction technique eventually confirmed the assigned chemical structure of the N-alkyl-β-enaminone 2 and pyridino-benzo[d]imidazole derivative 3. N-alkyl-β-enaminone 2 crystallized in the monoclinic space group P21/n with unit cell parameters of a = 9.8953(3) Å, b = 5.7545(2) Å, c = 21.7891(7) Å, and β =100.627(2)°, and with one molecule per asymmetric unit. On the other hand, compound 3 crystallized in the orthorhombic crystal system and space group P212121 with unit cell parameters of a = 6.82950(10) Å, b = 8.00540(10) Å, c = 22.4779(2) Å, and also with one molecule per asymmetric unit. Based on Hirshfeld analysis, the H...H (51.3%), O...H (10.0%), N...H (10.3%), and C...H (27.6%) contacts in 2 and the H...H (46.8%), O...H (9.9%), N...H (13.0%), and C...H (21.6%) in addition to the C…C (6.7%) interactions in 3 are the most important towards crystal stability via molecular packing. The main difference is the presence of π–π interaction among the molecular units of 3 but not in 2. The calculated 1H and 13C NMR chemical shifts showed good agreements with experimental data. Electronic properties and reactivity parameters of both compounds are also calculated and compared.

Albertiniite, Fe2+(SO3)·3H2O, a new sulfite mineral species from the Monte Falò Pb-Zn mine, Coiromonte, Armeno Municipality, Verbano Cusio Ossola Province, Piedmont, Italy

2016 ◽  
Vol 80 (6) ◽  
pp. 985-994 ◽  
Author(s):  
P. Vignola ◽  
G. D. Gatta ◽  
N. Rotiroti ◽  
P. Gentile ◽  
F. Hatert ◽  
...  
Keyword(s):  
Structure Refinement ◽  
Unit Cell ◽  
Iron Sulfides ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Calculated Density ◽  
Cell Parameters ◽  
Quartz Veins ◽  
Crystal Unit Cell ◽  
Brittle Fractures

AbstractAlbertiniite, Fe2+(SO3)·3H2O, is a new Fe2+ sulfite trihydrate, related chemically to gravegliaite. It occurs at the Monte Falò Pb-Zn mine near Coiromonte, in the Armeno Municipality, Verbano–Cusio–Ossola Province, Italy. It is an intermediate product of oxidation between iron sulfides and sulfates, forming monoclinic, colourless to pale yellow, transparent crystals with a vitreous lustre. The mineral occurs associated with stolzite, pyromorphite, hinsdalite, plumbogummite, gibbsite, scheelite and jarosite on brittle fractures of quartz veins or chlorite-schist. Albertiniite is optically biaxial (+) with 2V(meas) ≈ 40° and 2V(calc) = 66°. The measured refractive indices, using sodium light (589 nm) are: α = 1.612(2)°, β = 1.618(2)° and γ = 1.632(2)°. The optical axis plane is parallel to the perfect {010} cleavage plane. It is non-fluorescent under shortwave (254 nm) or longwave (366 nm) ultraviolet light. The calculated density is 2.469 g cm–3 (from the crystal-structure refinement), or 2.458 g cm–3 (from the chemical analysis and the single-crystal unit-cell parameters). The empirical formula is (average of 16 spots and based on 3 anhydrous oxygen apfu) (Ca0.001Mg0.001Na0.003)∑1.061(S0.971O3)·2.84H2O, with the H2O content calculated by difference to 100 wt.%. Albertiniite is monoclinic, with space group P21/n. Its unit-cell parameters are: a = 6.633(1), b = 8.831(1), c = 8.773(1) Å, β = 96.106(8)° and V = 511.0(1) Å3, with Z = 4. The eight strongest measured lines in the powder X-ray diffraction pattern are [d in Å, (I/I0), (hkl)]: 4.072 (100) (1̄11), 3.539 (93) (1̄12), 5.533 (27) (1̄01), 6.167 (14) (011), 2.830 (14) (211), 4.998 (14) (101), 4.353 (12) (111) and 3.897 (12) (012). The mineral, which has been approved by the CNMNC, number IMA2015-004, is named albertiniite in honour of Claudio Albertini, an Italian mineral collector and expert in the systematic mineralogy of the Alps and pegmatites.

scholarly journals Formation of an unexpected 3,3-diphenyl-3H-indazole through a facile intramolecular [2 + 3] cycloaddition of the diazo intermediate

2019 ◽  
Vol 15 ◽  
pp. 1347-1354
Author(s):  
Andrew T King ◽  
Hugh G Hiscocks ◽  
Lidia Matesic ◽  
Mohan Bhadbhade ◽  
Roger Bishop ◽  
...  
Keyword(s):  
Single Crystal ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
One Pot ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
X Ray Crystallography ◽  
The One ◽  
Close Contacts

The one-pot reaction of 2,6-bis(diphenylmethyl)-4-methoxyaniline with tert-butylnitrite, BTEAC and DABSO in the presence of CuCl2 provided an unexpected 3H-indazole product 8. The structure of the compound was determined by HRMS, IR, NMR and further confirmed by single crystal X-ray crystallography. The compound crystallises in the triclinic P-1 space group, with unit cell parameters a = 9.2107 (4), b = 10.0413 (5), c = 14.4363 (6) Å, α = 78.183 (2), β = 87.625 (2), γ = 71.975 (2)°. The formation of 8 proceeded through a facile intramolecular [2 + 3] cycloaddition of the diazo intermediate 9. The molecules of 8 are organised by edge–face Ar–H···π, face–face π···π, and bifurcated OCH2–H···N interactions. In addition to these, there are Ar–H···H–Ar close contacts, (edge–edge and surrounding inversion centres) arranged as infinite tapes along the a direction.

Synthesis and Characterization of A2CaCuO5(A=Nd, Sm)

1998 ◽  
Vol 12 (11) ◽  
pp. 427-431
Author(s):  
K. Jeyabalan ◽  
L. K. Kaliyaperumal ◽  
A. Sekar ◽  
J. Srinivas
Keyword(s):  
Diffraction Analysis ◽  
Unit Cell ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Orthorhombic Crystal ◽  
X Ray ◽  
Cell Parameters

Synthesis and characterization of A 2 CaCuO 5( A=Nd, Sm ) system is reported. Powder X-ray diffraction analysis shows that the compounds crystallizes in an orthorhombic crystal systems and the unit cell parameters are found to be a=6.399(9)Å, b=7.218(8) Å and c=12.167(17) Å for Nd 2 CaCuO 5 and a=5.872(8) Å, b=7.457(3) Å and c=12.682(18) Å for Sm 2 CaCuO 5.

scholarly journals X-ray, Hirshfeld surface analysis, spectroscopic and DFT studies of polycyclic aromatic hydrocarbons: Fluoranthene and acenaphthene

2015 ◽  
Vol 80 (12) ◽  
pp. 1489-1504 ◽  
Author(s):  
Wioleta Śmiszek-Lindert ◽  
Anna Michta ◽  
Aleksandra Tyl ◽  
Grzegorz Małecki ◽  
Elżbieta Chełmecka ◽  
...  
Keyword(s):  
Theoretical Calculations ◽  
Unit Cell ◽  
Computational Method ◽  
Orthorhombic Crystal ◽  
Monoclinic System ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Hirshfeld Surfaces ◽  
Polycyclic Aromatic

The X-ray structure, theoretical calculation, Hirshfeld surfaces analysis, IR and Raman spectra of fluoranthene and acenaphthene were reported. Acenaphthene crystallizes in the orthorhombic crystal system and space group P21ma, with crystal parameters a = 7.2053 (9) ?, b = 13.9800 (15) ?, c = 8.2638 (8) ?, Z = 4 and V = 832.41 (16) ?3. In turn, the grown crystals of fluoranthene are in monoclinic system with space group P21/n. The unit cell parameters are a = 18.3490 (2) ?, b = 6.2273 (5) ?, c = 19.8610 (2) ?, ? = 109.787 (13)?, Z = 8 and unit cell volume is 2135.50 (4) ?3. Theoretical calculations of the title compounds isolated molecule have been carried out using DFT at the B3LYP level. The intermolecular interactions in the crystal structure, for both the title PAHs, were analyzed using Hirshfeld surfaces computational method.

scholarly journals The Crystal Chemistry of Rathite Based on New Electron-Microprobe Data and Single-Crystal Structure Refinements: The Role of Thallium

Minerals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 466
Author(s):  
Dan Topa ◽  
Uwe Kolitsch
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Chemistry ◽  
Electron Microprobe ◽  
Mean Value ◽  
Unit Cell ◽  
Complex Spectrum ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Crystal Unit Cell

Crystal-structure refinements in space group P21/c were performed on five grains of rathite with different types and degrees of thallium, silver, and antimony substitutions, as well as quantitative electron-microprobe analyses of more than 800 different rathite samples. The results of these studies both enlarged and clarified the complex spectrum of cation substitutions and the crystal chemistry of rathite. The [Tl+ + As3+] ↔ 2Pb2+ scheme of substitution acts at the structural sites Pb1, Pb2, and Me6, the [Ag+ + As3+] ↔ 2Pb2+ substitution at Me5, and the Sb-for-As substitution at the Me3 site only. The homogeneity range of rathite was determined to be unusually large, ranging from very Tl-poor compositions (0.16 wt%; refined single-crystal unit-cell parameters: a = 8.471(2), b = 7.926(2), c = 25.186(5) Å, β = 100.58(3)°, V = 1662.4(6) Å3) to very Tl-rich compositions (11.78 wt%; a = 8.521(2), b = 8.005(2), c = 25.031(5) Å, β = 100.56(3)°, V = 1678.4(6) Å3). The Ag content is only slightly variable (3.1 wt%–4.1 wt%) with a mean value of 3.6 wt%. The Sb content is strongly variable (0.20 wt%–7.71 wt%) and not correlated with the Tl content. With increasing Tl content (0.16 wt%–11.78 wt%), a clear increase of the unit-cell parameters a, b, and V, and a slight decrease of c is observed, although this is somewhat masked by the randomly variable Sb content. The revised general formula of rathite may be written as AgxTlyPb16−2(x+y)As16+x+y−zSbzS40 (with 1.6 < x < 2, 0 < y < 3, 0 < z < 3.5). Based on Pb–S bond lengths, polyhedral characteristics and Pb-site bond-valence sums, we conclude that the Pb1 site is more affected by Tl substitution than the Pb2 site. When Tl substitution reaches values above 13 wt% (or 3 apfu), a new phase (“SR”), belonging to the rahite group, appears as lamellar exsolution intergrowths with Tl-rich rathite (11.78 wt%). Rathite is found only in the Lengenbach and Reckibach deposits, Binntal, Canton Wallis, Switzerland.

The incommensurately modulated crystal structure of roshchinite, Cu0.09Ag1.04Pb0.65Sb2.82As0.37S6.08

2018 ◽  
Vol 233 (3-4) ◽  
pp. 255-267 ◽  
Author(s):  
Emil Makovicky ◽  
Berthold Stöger ◽  
Dan Topa
Keyword(s):  
Crystal Structure ◽  
Crystal Lattice ◽  
Second Order ◽  
Unit Cell ◽  
Orthorhombic Crystal ◽  
Probable Reason ◽  
Structure Solution ◽  
Compositional Changes ◽  
Parallel Configuration ◽  
The One

AbstractThe Pb–Ag–Sb sulfide roshchinite, Cu0.09Ag1.04Pb0.65Sb2.82As0.37S6.08, is a lillianite homologue N=4 with a complex incommensurate superstructure in the 8.46 Å direction of the orthorhombic crystal lattice witha19.0804(1) Å,b8.4591(2) Å andc12.9451(3) Å, superspace groupPbcn(0σ20)00s,q=0.41458(3)b*. A structure solution and refinement in (3+1) superspace, based on 10,019 observed reflections and 437 refined parameters was terminated at Robs(wR) equal to 7.27 (8.07)% using satellites up to second order; Robsis 4.82 for main reflections only. The Pb atoms in trigonal coordination prisms on planes of unit-cell twinning are semiperiodically replaced by antimony. The marginal columns of (311)PbSslabs of the Sb–Ag based structure which is based on PbS-like topology contain Sb, Ag(Cu) and mixed Ag/Sb sites in a complicated sequence. Central portions of the slabs are occupied by Sb–S crankshaft chains, best exposed on the (100)PbSplanes, which run diagonally across the slabs. In these planes, in their majority the chains display Sb3S4form and two opposing orientations, zig-zagging along the [010] direction. Every six chains, a parallel configuration of two chains occurs, but occasionally this interval is reduced to five chains. This, together with related compositional changes in the Pb– and Ag–Sb column, explains the one-dimensionally incommensurate character of roshchinite. Modestly elevated contents of As replacing Sb are the probable reason of modulation and non-commensurability in roshchinite.

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