Crystal structure of Cd5(CN)10(H2O)4.cntdot.4C6H11OH studied by x-ray diffraction and solid-state cadmium-113 NMR. A new type of cristobalite-like framework host with a site interacting with cyclohexanol by hydrogen bonding

The crystal structure of naphthazarin C has been determined by neutron diffraction at 60 and 300 K (λ ═ 0.895 Å; 1 Å ═ 10 -10 m ═ 10 -1 nm) and X-ray diffraction at 300 K. The space group is Pc at 60 K, but P 2 1 /c at 300 K. There are small but significant differences in cell dimensions at the two temperatures: a ═ 7.664 (7.915), b ═ 7.304 (7.262), c ═ 15.16 (15.284) Å; β ═ 114.60 (114.20)°; Z ═ 4; U ═ 771.6 (801.3) Å 3 (values at 300 K in parentheses). Neutron diffraction shows that the Pc and P 2 1 /c structures are related by an order-disorder transition at 110±1 K. Structure analysis (1771 reflections; R F ═ 0.035; R W ═ 0.036) showed that the hydroxyl hydrogens are largely ordered at 60 K, the appropriate molecular formula being 5, 8-dihydroxy-1, 4-naphthadione. Neutron diffraction measurements at 300 K (1769 reflections; R F ═ 0.052) indicated a disordered molecular model with one-half of an hydrogen atom attached to each oxygen. X -ray diffraction measurements on naphthazarin C at 300 K (two independent sets of intensity measurements, one with CuKα and the other with MoKα) support this disordered model. The molecular dimensions for naphthazarin A and B also fit this model. Comparison of the crystal structure of naphthazarin C with those of the A and B polymorphs shows that only the former has intermolecular O─H • • • O hydrogen bonding. The diffraction results combined with the available solid-state n. m. r. data show that there is at room temperature a rapid intramolecular exchange of hydroxylic protons between each pair of oxygen atoms in all three naphthazarin polymorphs. Many 1, 3-diketones exist in an enol form in the solid. These enol forms have been reported to be disordered for about twenty molecules at room temperature (this total includes one molecule studied at 108 K, and four amino-imino systems) and ordered systems have been reported for about fifteen molecules. Intermolecular hydrogen bonding occurs only in a few of these crystals.

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Crystal structure of an inclusion complex between chiral monoaza-15-crown-5 and S(–)-1-phenyl-ethyl ammonium percholorate

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.218.5.381.20734 ◽

2003 ◽

Vol 218 (5) ◽

Cited By ~ 5

Author(s):

Süheyla Özbey ◽

F. B. Kaynak ◽

M. Toğrul ◽

N. Demirel ◽

H. Hoşgören

Keyword(s):

Crystal Structure ◽

Inclusion Complex ◽

Single Crystal ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

New Type

AbstractA new type of inclusion complex, S(–)-1 phenyl ethyl ammonium percholorate complex of R-(–)-2-ethyl - N - benzyl - 4, 7, 10, 13 - tetraoxa -1- azacyclopentadecane, has been prepared and studied by NMR, IR and single crystal X-ray diffraction techniques. The compound crystallizes in space group

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A 2-D Zn(II) coordination polymer based on 4,5-imidazoledicarboxylate and bis(benzimidazole) ligands: synthesis, crystal structure and fluorescence properties

Zeitschrift für Naturforschung B ◽

10.1515/znb-2021-0003 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Xinzhao Xia ◽

Lixian Xia ◽

Geng Zhang ◽

Yuxuan Jiang ◽

Fugang Sun ◽

...

Keyword(s):

Crystal Structure ◽

Coordination Polymer ◽

Zigzag Chain ◽

Supramolecular Framework ◽

X Ray Diffraction ◽

Hydrothermal Conditions ◽

Hydrogen Bond Interaction ◽

X Ray ◽

New Type ◽

Solid State Fluorescence

Abstract In this work, a new type of zinc(II) coordination polymer {[Zn(HIDC)(BBM)0.5]·H2O} n (Zn-CP) was synthesized using 4,5-imidazoledicarboxylic acid (H3IDC) and 2,2-(1,4-butanediyl)bis-1,3-benzimidazole (BBM) under hydrothermal conditions. Its structure has been characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction analysis. The Zn(II) ion is linked by the HIDC2− ligand to form a zigzag chain by chelating and bridging, and then linked by BBM to form a layered network structure. Adjacent layers are further connected by hydrogen bond interaction to form a 3-D supramolecular framework. The solid-state fluorescence performance of Zn-CP shows that compared with free H3IDC ligand, its fluorescence intensity is significantly enhanced.

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Exploring the Structural Chemistry of Pyrophosphoramides: N,N′,N″,N‴-Tetraisopropylpyrophosphoramide

Chemistry ◽

10.3390/chemistry3010013 ◽

2021 ◽

Vol 3 (1) ◽

pp. 149-163

Author(s):

Duncan Micallef ◽

Liana Vella-Zarb ◽

Ulrich Baisch

Keyword(s):

Crystal Structure ◽

Mass Spectrometry ◽

Nuclear Magnetic Resonance ◽

Hydrogen Bonding ◽

Nmr Spectroscopy ◽

Ir Spectroscopy ◽

Room Temperature ◽

Intermolecular Hydrogen Bonding ◽

X Ray Diffraction ◽

X Ray

N,N′,N″,N‴-Tetraisopropylpyrophosphoramide 1 is a pyrophosphoramide with documented butyrylcholinesterase inhibition, a property shared with the more widely studied octamethylphosphoramide (Schradan). Unlike Schradan, 1 is a solid at room temperature making it one of a few known pyrophosphoramide solids. The crystal structure of 1 was determined by single-crystal X-ray diffraction and compared with that of other previously described solid pyrophosphoramides. The pyrophosphoramide discussed in this study was synthesised by reacting iso-propyl amine with pyrophosphoryl tetrachloride under anhydrous conditions. A unique supramolecular motif was observed when compared with previously published pyrophosphoramide structures having two different intermolecular hydrogen bonding synthons. Furthermore, the potential of a wider variety of supramolecular structures in which similar pyrophosphoramides can crystallise was recognised. Proton (1H) and Phosphorus 31 (31P) Nuclear Magnetic Resonance (NMR) spectroscopy, infrared (IR) spectroscopy, mass spectrometry (MS) were carried out to complete the analysis of the compound.

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A MOF based on a lead(II) 2-oxido-6-methylpyridine-4-carboxylate network

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0208 ◽

2020 ◽

Vol 75 (4) ◽

pp. 365-369

Author(s):

Long Tang ◽

Yu Pei Fu ◽

Na Cui ◽

Ji Jiang Wang ◽

Xiang Yang Hou ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Carboxylic Acid ◽

Thermogravimetric Analysis ◽

Metal Organic Framework ◽

X Ray Diffraction ◽

X Ray ◽

Connected Node ◽

Metal Organic ◽

Solid State Fluorescence

AbstractA new metal-organic framework, [Pb(hmpcaH)2]n (1), has been hydrothermally synthesized from Pb(OAc)2 · 3H2O and 2-hydroxy-6-methylpyridine-4-carboxylic acid (hmpcaH2; 2), and characterized by IR spectroscopy, elemental and thermogravimetric analysis, and single-crystal X-ray diffraction. In complex 1, each hmpcaH− ligand represents a three-connected node to combine with the hexacoordinated Pb(II) ions, generating a 3D binodal (3,6)-connected ant network. The crystal structure of 2 was determined. The solid-state fluorescence properties of 1 and 2 were investigated.

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Crystal Structure Refinements of Four Monazite Samples from Different Localities

Minerals ◽

10.3390/min10111028 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1028 ◽

Cited By ~ 1

Author(s):

M. Mashrur Zaman ◽

Sytle M. Antao

Keyword(s):

Crystal Structure ◽

Electron Probe ◽

Unit Cell Volume ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Large Unit Cell ◽

A Site

This study investigates the crystal chemistry of monazite (APO4, where A = Lanthanides = Ln, as well as Y, Th, U, Ca, and Pb) based on four samples from different localities using single-crystal X-ray diffraction and electron-probe microanalysis. The crystal structure of all four samples are well refined, as indicated by their refinement statistics. Relatively large unit-cell parameters (a = 6.7640(5), b = 6.9850(4), c = 6.4500(3) Å, β = 103.584(2)°, and V = 296.22(3) Å3) are obtained for a detrital monazite-Ce from Cox’s Bazar, Bangladesh. Sm-rich monazite from Gunnison County, Colorado, USA, has smaller unit-cell parameters (a = 6.7010(4), b = 6.9080(4), c = 6.4300(4) Å, β = 103.817(3)°, and V = 289.04(3) Å3). The a, b, and c unit-cell parameters vary linearly with the unit-cell volume, V. The change in the a parameter is large (0.2 Å) and is related to the type of cations occupying the A site. The average <A-O> distances vary linearly with V, whereas the average <P-O> distances are nearly constant because the PO4 group is a rigid tetrahedron.

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Investigation of Solvatomorphism and Its Photophysical Implications for Archetypal Trinuclear Au3(1-Methylimidazolate)3

Molecules ◽

10.3390/molecules26154404 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4404

Author(s):

Shengyang Guan ◽

David C. Mayer ◽

Christian Jandl ◽

Sebastian J. Weishäupl ◽

Angela Casini ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Density Functional ◽

Bulk Material ◽

Variable Temperature ◽

Active Phase ◽

Solvent Free ◽

X Ray Diffraction ◽

X Ray ◽

Aurophilic Interactions

A new solvatomorph of [Au3(1-Methylimidazolate)3] (Au3(MeIm)3)—the simplest congener of imidazolate-based Au(I) cyclic trinuclear complexes (CTCs)—has been identified and structurally characterized. Single-crystal X-ray diffraction revealed a dichloromethane solvate exhibiting remarkably short intermolecular Au⋯Au distances (3.2190(7) Å). This goes along with a dimer formation in the solid state, which is not observed in a previously reported solvent-free crystal structure. Hirshfeld analysis, in combination with density functional theory (DFT) calculations, indicates that the dimerization is generally driven by attractive aurophilic interactions, which are commonly associated with the luminescence properties of CTCs. Since Au3(MeIm)3 has previously been reported to be emissive in the solid-state, we conducted a thorough photophysical study combined with phase analysis by means of powder X-ray diffraction (PXRD), to correctly attribute the photophysically active phase of the bulk material. Interestingly, all investigated powder samples accessed via different preparation methods can be assigned to the pristine solvent-free crystal structure, showing no aurophilic interactions. Finally, the observed strong thermochromism of the solid-state material was investigated by means of variable-temperature PXRD, ruling out a significant phase transition being responsible for the drastic change of the emission properties (hypsochromic shift from 710 nm to 510 nm) when lowering the temperature down to 77 K.

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