Magnetic Switching in Vapochromic Oxalato-Bridged 2D Copper(II)- Pyrazole Compounds for Biogenic Amine Sensing

A new two-dimensional (2D) coordination polymer of the formula {Cu(ox)(4-Hmpz)·1/3H2O}n (1) (ox = oxalate and 4-Hmpz = 4-methyl-1H-pyrazole) has been prepared, and its structure has been determined by single-crystal X-ray diffraction. It consists of corrugated oxalato-bridged copper(II) neutral layers featuring two alternating bridging modes of the oxalate group within each layer, the symmetric bis-bidentate (μ-κ2O1,O2:κ2O2′,O1′) and the asymmetric bis(bidentate/monodentate) (μ4-κO1:κ2O1,O2:κO2′:κ2O2′,O1′) coordination modes. The three crystallographically independent six-coordinate copper(II) ions that occur in 1 have tetragonally elongated surroundings with three oxygen atoms from two oxalate ligands, a methylpyrazole-nitrogen defining the equatorial plane, and two other oxalate-oxygen atoms occupying the axial positions. The monodentate 4-Hmpz ligands alternatively extrude above and below each oxalate-bridged copper(II) layer, and the water molecules of crystallization are located between the layers. Compound 1 exhibits a fast and selective adsorption of methylamine vapors to afford the adsorbate of formula {Cu(ox)(4-Hmpz)·3MeNH2·1/3H2O}n (2), which is accompanied by a concomitant color change from cyan to deep blue. Compound 2 transforms into {Cu(ox)(4-Hmpz)·MeNH2·1/3H2O}n (3) under vacuum for three hours. The cryomagnetic study of 1–3 revealed a unique switching from strong (1) to weak (2 and 3) antiferromagnetic interactions. The external control of the optical and magnetic properties along this series of compounds might make them suitable candidates for switching optical and magnetic devices for chemical sensing.

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Synthesis and Complexation Properties of 2-Hydroxy-5-methoxyphenylphosphonic Acid (H3L1). Crystal Structure of the [Cu(H2L1)2(Н2О)2] Complex

Russian Journal of General Chemistry ◽

10.1134/s1070363221110074 ◽

2021 ◽

Vol 91 (11) ◽

pp. 2176-2186

Author(s):

G. S. Tsebrikova ◽

Yu. I. Rogacheva ◽

I. S. Ivanova ◽

A. B. Ilyukhin ◽

V. P. Soloviev ◽

...

Keyword(s):

Crystal Structure ◽

Hydrogen Bond ◽

Methoxy Group ◽

Protonation Constants ◽

Water Molecules ◽

X Ray Diffraction ◽

X Ray ◽

The Stability ◽

Intramolecular Hydrogen ◽

Oxygen Atoms

Abstract 2-Hydroxy-5-methoxyphenylphosphonic acid (H3L1) and the complex [Cu(H2L1)2(H2O)2] were synthesized and characterized by IR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The polyhedron of the copper atom is an axially elongated square bipyramid with oxygen atoms of phenolic and of monodeprotonated phosphonic groups at the base and oxygen atoms of water molecules at the vertices. The protonation constants of the H3L1 acid and the stability constants of its Cu2+ complexes in water were determined by potentiometric titration. The protonation constants of the acid in water are significantly influenced by the intramolecular hydrogen bond and the methoxy group. The H3L1 acid forms complexes CuL‒ and CuL24‒ with Cu2+ in water.

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A Rare Example of a Dinuclear Cobalt(II) Complex with Dipicolinate and Bridging 2-Aminopyrazine Ligands. Preparation, Structural, Spectroscopic and Thermal Characterization

Zeitschrift für Naturforschung B ◽

10.1515/znb-2011-0805 ◽

2011 ◽

Vol 66 (8) ◽

pp. 813-818 ◽

Cited By ~ 2

Author(s):

Masoumeh Tabatabaee ◽

Boris-Marko Kukovec ◽

Vajieh Razavimahmoudabadi

Keyword(s):

Dipicolinic Acid ◽

3D Structure ◽

Thermal Characterization ◽

Water Molecules ◽

X Ray Diffraction ◽

Coordination Environment ◽

Distorted Octahedral ◽

Elemental Analyses ◽

Coordinated Water ◽

Oxygen Atoms

A dinuclear cobalt(II) complex, [Co2(H2O)4(dipic)2(μ-apyz)] (dipicH2 = pyridine-2,6-dicarboxylic (dipicolinic) acid, apyz = 2-aminopyrazine) (1), has been hydrothermally synthesized and characterized by elemental analyses, spectroscopic methods (IR, UV/Vis), thermal analysis as well as by X-ray diffraction studies. The dinuclear complex is composed of two cobalt(II) ions bridged by a 2-aminopyrazine molecule. Each cobalt(II) ion is coordinated by one nitrogen and two oxygen atoms of the tridentate dipicolinate anion, one heterocyclic nitrogen atom of the 2-aminopyrazine and two oxygen atoms of coordinated water molecules. The resulting geometry for the CoN2O4 coordination environment can be described as distorted octahedral. Various hydrogen bonds of the type O-H···O and N-H···O are also present in the crystal structure. This arrangement leads to the formation of a 3D structure.

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X-ray structure of 1D-coordination polymer of copperII bearing 1,4-pyrazine-2,3-dicarboxylic acid and 2-aminopyrimidine

Journal of the Serbian Chemical Society ◽

10.2298/jsc101115153m ◽

2012 ◽

Vol 77 (1) ◽

pp. 67-73 ◽

Cited By ~ 3

Author(s):

Masoud Mirzaei ◽

Hossein Eshtiagh-Hosseini ◽

Azam Hassanpoor ◽

Victor Barba

Keyword(s):

Coordination Polymer ◽

Dicarboxylic Acid ◽

Supramolecular Assembly ◽

Axial Position ◽

Water Molecules ◽

X Ray Diffraction ◽

Double Chain ◽

X Ray ◽

1D Coordination Polymer ◽

Oxygen Atoms

The new 1D-coordination polymer of CuII ion, {(2- apymH)2[Cu(pyzdc)2] .6H2O}n, (2-apym = 2-aminopyrimidine, pyzdcH2 = 1,4- pyrazine-2,3-dicarboxylic acid), was synthesized based on proton transfer mechanism and characterized by elemental analysis, infrared spectroscopy, and single crystal X-ray diffraction. The coordination polymer consists of infinite anionic chains of [Cu(pyzdc)2]2- anion bridged crossing double chain running along a-axis and discrete (2-apymH)+ fragment. The CuII ion is located on inversion centre in the basal plane of an elongated octahedron and two oxygen atoms from adjacent (pyzdc)2-ligands occupy axial position. The interaction between oxygen atoms of water molecules along with the dicarboxylic acid play an important role in the overall supramolecular assembly.

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The crystal structures of sjögrenite and pyroaurite

Mineralogical Magazine and Journal of the Mineralogical Society ◽

10.1180/minmag.1967.036.280.01 ◽

1967 ◽

Vol 36 (280) ◽

pp. 465-479 ◽

Cited By ~ 125

Author(s):

L. Ingram ◽

H. F. W. Taylor

Keyword(s):

Crystal Structures ◽

Three Dimensional ◽

Water Molecules ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

Approximate Composition ◽

Oxygen Atoms

SummaryThe crystal structures of sjögrenite and pyroaurite, two stacking modifications of approximate composition Mg6Fe2(OH)16(CO3).4H2O, have been determined by X-ray diffraction using three-dimensional methods. Sjögrenite is hexagonal, with a 3·13, c 15·66 Å, space group P63/mmc , Z = ¼; pyroaurite is rhombohedral, with aH 3·13, cH 23·49 Å, space group R3̄m or R3m, Z = ⅜. Both structures are based on brucite-like layers, with magnesium and iron distributed among the octahedral positions. The cations appear to be largely disordered, although ordered regions may occur in some crystals. Between the brucite-like layers are the water molecules and carbonate groups. These are statistically arranged, with their oxygen atoms distributed among a larger number of possible sites.

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The X-ray structure of a sodium peroxide hydrate, Na2O2•8H2O, and its reactions with carbon dioxide: relevance to the brightening of mechanical pulps

Canadian Journal of Chemistry ◽

10.1139/v97-006 ◽

1997 ◽

Vol 75 (1) ◽

pp. 46-51 ◽

Cited By ~ 7

Author(s):

Geoffrey S. Hill ◽

David G. Holah ◽

Stephen D. Kinrade ◽

Todd A. Sloan ◽

Vincent R. Magnuson ◽

...

Keyword(s):

Water Molecules ◽

Monoclinic Space Group ◽

Sodium Peroxide ◽

X Ray Diffraction ◽

X Ray ◽

Mechanical Pulps ◽

Main Component ◽

Key Words Sodium ◽

Centrosymmetric Structure ◽

Oxygen Atoms

The main component of the solid originally believed to be a peroxosilicate with pulp-brightening properties has been shown to be Na2O2•8H2O. The solid crystallizes in the monoclinic space group C2/c, with an empirical formula H8O5Na, and with a = 14.335(3), b = 6.461(1), c = 11.432(2) Å, β = 118.28(3)°, and Z = 8. The centrosymmetric structure consists of a peroxide anion with an O—O distance of 1.499(2) Å. Each of these oxygen atoms is at the apex of an approximate square-based pyramid, the base of which consists of four oxygen atoms of water molecules. The bases of the two pyramids are staggered when viewed down the peroxide bond. Each sodium is at the centre of an approximate octahedron of water molecules, four of which bridge other sodium atoms and two bridge to the peroxide anions. One hydrogen atom of each of these two water molecules is terminal and the other two are hydrogen bonded to peroxide oxygen atoms. The compound reacts very rapidly with CO2 in moist air to form Na2CO3, but in drier conditions, formation of the carbonate can take many days and proceeds via a percarbonate, believed to be Na2CO4. This has been identified by infrared spectroscopy and X-ray powder diffraction and can persist for long periods in dry air. Key words: sodium peroxide hydrate, sodium percarbonate, pulp brightening, X-ray diffraction, infrared.

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{Co(H2O)2[C6(COO)6]}n4n— — Ein neuartiges kettenförmiges Polyanion in Co3[C6(COO)6]·18H2O (Tricobalt(II)mellitat Octadecahydrat) / {Co(H2O)2[C6(COO)6]}n4n— – A Novel Chain-Like Polyanion in Co3[C6(COO)6]·18 H2O (Tricobalt(II) Mellitate Octadeca Hydrate)

Zeitschrift für Naturforschung B ◽

10.1515/znb-1991-0909 ◽

1991 ◽

Vol 46 (9) ◽

pp. 1188-1192 ◽

Cited By ~ 24

Author(s):

Christian Robl ◽

Stephanie Hentschel

Keyword(s):

Crystal Structure ◽

Single Crystals ◽

Ligand Exchange ◽

Negative Charge ◽

Water Molecules ◽

Carboxylate Oxygen ◽

Deep Blue ◽

Carboxylate Groups ◽

Excess Negative Charge ◽

Oxygen Atoms

Red orthorhombic single crystals of Co3[C6(COO)6]·18 H2O were grown in aqueous silica gel (space group Pbca, a = 852.7(2), b = 2015.6(3), c = 1712.3(3) pm, 269 parameters, 2675 reflections, Rg = 0.0217). The Co2+ ions are coordinated octahedrally by water molecules and oxygen atoms of carboxylate groups. Co(1) is bound to five water molecules and one carboxylate oxygen atom, Co(2) is situated on a crystallographic center of symmetry and coordinated by four carboxylate oxygen atoms and two water molecules. Folded chains extending parallel to [100] made up by Co(2) and mellitate hexaanions with composition {Co(H2O)2[C6(COO)6]}n4n— are the main feature of the crystal structure. The excess negative charge is compensated for by Co(1) cations bound to these chains via carboxylate groups related by a center of symmetry. Hydrogen bonds connect neighbouring chains primarily with carboxylate oxygen atoms which are not bound to Co2+ as the proton acceptors. Endothermic loss of water was observed to commence at 120 °C, followed (in air) by a further exothermic two step decomposition at 370 and 450 °C to yield Co3O4 as a crystalline residue. With (CH3)2SO a topotactical ligand exchange occurs without destruction of the single crystals causing the colour of the compound to change to deep-blue.

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On the Structure in Aqueous Superconcentrated Calcium Nitrate

Zeitschrift für Naturforschung A ◽

10.1515/zna-1981-0808 ◽

1981 ◽

Vol 36 (8) ◽

pp. 831-835 ◽

Cited By ~ 1

Author(s):

R. Caminiti ◽

A. Musinu ◽

G. Paschina ◽

G. Piccaluga ◽

G. Pinna

Keyword(s):

Experimental Data ◽

Calcium Ions ◽

Calcium Nitrate ◽

Water Molecules ◽

X Ray Diffraction ◽

X Ray ◽

Crystalline Hydrates ◽

Oxygen Atoms

Abstract Liquid hydrous calcium nitrate of composition Ca(NO3)2 · 3.5 H2O was investigated by X-ray diffraction. Experimental data were interpreted in terms of geometrical models suggested by the structure of the crystalline hydrates Ca (NO3)2 · 3H2O and Ca(NO3)2 · 4H2O, in which calcium ions are coordinated to nine oxygen atoms, partly coming from water molecules, partly from NO3-ions.

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Synthesis, Structural Characterization, and Antibacterial Activity of Novel Erbium(III) Complex Containing Antimony

Bioinorganic Chemistry and Applications ◽

10.1155/2018/4313197 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9

Author(s):

Ting Liu ◽

Rong-Gui Yang ◽

Guo-Qing Zhong

Keyword(s):

Ethylenediaminetetraacetic Acid ◽

Antimicrobial Activities ◽

Diffusion Method ◽

Water Molecules ◽

Equatorial Position ◽

X Ray Diffraction ◽

Monoclinic System ◽

Adjacent Layer ◽

X Ray ◽

Oxygen Atoms

The novel 3D edta-linked heterometallic complex [Sb2Er(edta)2(H2O)4]NO3·4H2O (H4edta = ethylenediaminetetraacetic acid) was synthesized and characterized by elemental analyses, single-crystal X-ray diffraction, powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermal analysis. The complex crystallizes in the monoclinic system with space group Pm. In the complex, each erbium(III) ion is connected with antimony(III) ions bridging by four carboxylic oxygen atoms, and in each [Sb(edta)]− anion, the antimony(III) ion is hexacoordinated by two nitrogen atoms and four oxygen atoms from the edta4− ions, together with a lone electron pair at the equatorial position. The erbium(III) ion is octacoordinated by four oxygen atoms from four different edta4− ions and four oxygen atoms from the coordinated water molecules. The carboxylate bridges between antimony and erbium atoms form a planar array, parallel to the (1 0 0) plane. There is an obvious weak interaction between antimony atom and oxygen atom of the carboxyl group from the adjacent layer. The degradation of the complex proceeds in several steps and the water molecules and ligands are successively emitted, and the residues of the thermal decomposition are antimonous oxide and erbium(III) oxide. The complex was evaluated for its antimicrobial activities by agar diffusion method, and it has good activities against the test bacterial organisms.

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Synthesis and Structural Characterization of the Tetranuclear Iron(Iii) Cluster with Salicylic Acid

Chemistry Journal of Moldova ◽

10.19261/cjm.2020.758 ◽

2020 ◽

Vol 15 (2) ◽

pp. 62-68

Author(s):

Viorina Gorinchoy

Keyword(s):

Salicylic Acid ◽

Diffraction Analysis ◽

Structural Characterization ◽

Spectroscopic Method ◽

Water Molecules ◽

X Ray Diffraction ◽

X Ray ◽

Ir Spectroscopic ◽

Oxygen Atoms

A new tetra-homonuclear iron(III) cluster, [Fe4O2(Sal)4(H2O)6]·4DMA·0.75H2O, where Sal= salicylic acid and DMA= N,N-dimethylacetamide consolidated via two µ3-oxo- and four salicylate-bridges was synthesized and characterized by IR spectroscopic method as well as by single crystal X-ray diffraction analysis. The structure of the obtained tetranuclear compound consists of four FeIII atoms in a “butterfly” arrangement. The coordination sphere of each of the two central FeIII atoms is generated by two μ3-oxo-bridging atoms and four oxygen atoms provided by the tridentate-bridging Sal2- ligands, while the coordination polyhedron of another two iron atoms involve six oxygen atoms from three water molecules, two salicylic and one μ3-oxigen atom. The Fe-O distances within Fe-O-Fe bridge are of 2.102(3) Å (for wing-body) and 2.038(3) Å (for body-body).

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Triazolite, NaCu2(N3C2H2)2(NH3)2Cl3·4H2O, a new mineral species containing 1,2,4-triazolate anion, from a guano deposit at Pabellón de Pica, Iquique Province, Chile

Mineralogical Magazine ◽

10.1180/minmag.2017.081.088 ◽

2018 ◽

Vol 82 (4) ◽

pp. 1007-1014 ◽

Cited By ~ 4

Author(s):

Nikita V. Chukanov ◽

Natalia V. Zubkova ◽

Gerhard Möhn ◽

Igor V. Pekov ◽

Dmitriy I. Belakovskiy ◽

...

Keyword(s):

Direct Methods ◽

New Mineral ◽

Water Molecules ◽

X Ray Diffraction ◽

Orthorhombic Space Group ◽

Ammine Complex ◽

X Ray ◽

Deep Blue ◽

New Mineral Species ◽

Mohs Hardness

ABSTRACTThe new mineral triazolite is found in a guano deposit located on the Pabellón de Pica Mountain, Iquique Province, Tarapacá Region, Chile. Associated minerals are salammoniac, halite, dittmarite, joanneumite, chanabayaite, nitratine, natroxalate and möhnite. Triazolite occurs as deep blue prismatic crystals up to 0.1 mm × 0.15 mm × 0.75 mm and their radial aggregates up to 1.5 mm across. The mineral is brittle. Its Mohs hardness is 2.Dcalc= 2.028 g cm–3. The infrared spectrum shows the presence of 1,2,4-triazolate anion and ammonia and water molecules. Triazolite is optically biaxial (–), α = 1.582(4), β = 1.625(3), γ = 1.625(3) and 2Vmeas= 5(3)°. The chemical composition (electron-microprobe data for Cl, Na, Fe and Cu; H, C, N and S contents were measured by gas chromatography of products of ignition at 1200°C; wt.%) is: Na 4.91, Fe 1.51, Cu 22.06, Cl 19.80, S 1.4, C 7.7, H 4.4, N 24.2, O (calc.) 12.83, total 98.81. The empirical formula is Na1.14(Cu1.86Fe0.14)(Cl2.99S0.23)N9.23C3.43H23.34O4.29. The idealized formula is NaCu2(N3C2H2)2(NH3)2Cl3·4H2O. Triazolite is a metalorganic ammine complex in which 1,2,4-triazolate anion and ammonia molecule are ligands coordinating Cu2+. The crystal structure was solved by direct methods and refined toR= 0.0242 based on 4210 unique reflections withI> 2σ(I). Triazolite is orthorhombic, space groupP212121,a= 19.3575(5),b= 7.15718(19),c= 12.5020(4) Å,V= 1732.09(8) Å3andZ= 4. The eight strongest reflections of the powder X-ray diffraction pattern [d, Å (I,%) (hkl)] are: 10.22 (97) (101), 6.135 (40) (011), 5.696 (17) (301), 5.182 (59) (202), 5.119 (100) (211), 4.854 (19) (400), 3.752 (16) (312, 501), 3.294 (18) (221). Triazolite is named for the presence of 1,2,4-triazolate anion.

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