scholarly journals Ultrasound-Assisted Synthesis and Crystal Structure of Novel 2D Cd (II) Metal–Organic Coordination Polymer with Nitrite End Stop Ligand as a Precursor for Preparation of CdO Nanoparticles

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 197
Author(s):  
Younes Hanifehpour ◽  
Jaber Dadashi ◽  
Babak Mirtamizdoust

In the present research, a sonochemical approach was applied to prepare new cadmium(II) coordination 2D polymer, [Cd(L)(NO2)2]n (L = 1,2-bis(1-(pyridin-3-yl)ethylidene)hydrazine) and structurally characterized with various spectroscopic techniques including XRD, elemental analysis, SEM, and IR spectroscopy. The coordination number of cadmium (II) ions is seven (CdN2O5) by two nitrogen atoms from two organic Schiff base ligand and five oxygen of nitrite anions. The 2D sheet structures ended by nitrite anions and the nitrite anion displayed the end-stop role. The comprehensive system showed a three-dimensional structure with several weak interactions. The high-intensity ultrasound is regarded as an easy, environmentally-friendly, and flexible synthetic instrument for the compounds of coordination. CdO NPs was obtained by thermolysing 1 at 180 °C with oleic acid (as a surfactant). Further, the size and morphology of the produced CdO nanoparticles were investigated through SEM.

2019 ◽  
Author(s):  
Isaiah R. Speight ◽  
Igor Huskić ◽  
Mihails Arhangelskis ◽  
Hatem M. Titi ◽  
Robin Stein ◽  
...  

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.


2019 ◽  
Author(s):  
Isaiah R. Speight ◽  
Igor Huskić ◽  
Mihails Arhangelskis ◽  
Hatem M. Titi ◽  
Robin Stein ◽  
...  

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.


Agronomy ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 56 ◽  
Author(s):  
Eric Bertoft

Starch is a major food supply for humanity. It is produced in seeds, rhizomes, roots and tubers in the form of semi-crystalline granules with unique properties for each plant. Though the size and morphology of the granules is specific for each plant species, their internal structures have remarkably similar architecture, consisting of growth rings, blocklets, and crystalline and amorphous lamellae. The basic components of starch granules are two polyglucans, namely amylose and amylopectin. The molecular structure of amylose is comparatively simple as it consists of glucose residues connected through α-(1,4)-linkages to long chains with a few α-(1,6)-branches. Amylopectin, which is the major component, has the same basic structure, but it has considerably shorter chains and a lot of α-(1,6)-branches. This results in a very complex, three-dimensional structure, the nature of which remains uncertain. Several models of the amylopectin structure have been suggested through the years, and in this review two models are described, namely the “cluster model” and the “building block backbone model”. The structure of the starch granules is discussed in light of both models.


Author(s):  
Avijit Kumar Paul

The mixed-metal sulfate, KEu(SO4)2·H2O, has been obtained as a new polymorph using hydrothermal conditions. The crystal structure is isotypic with NaCe(SO4)2·H2O and shows a three-dimensional connectivity of the tetrahedral sulfate units with EuIII and KI ions. Tricapped trigonal–prismatic EuO9 units and square-antiprismatic KO8 units link the SO4 tetrahedra, building the three-dimensional structure. Topological analysis reveals the existence of two nodes with 6- and 10-connected nets. The compound was previously reported [Kazmierczak & Höppe (2010). J. Solid State Chem. 183, 2087–2094] in the monoclinic space group P21/c with a similar structural connectivity and coordination environments to the present compound.


MRS Advances ◽  
2016 ◽  
Vol 1 (29) ◽  
pp. 2155-2160
Author(s):  
Eri A. Takami ◽  
Folarin Erogbogbo

ABSTRACTLipid-polymer hybrid nanoparticles (LPHN) have great potential as drug delivery devices for treatment of serious medical issues such as cardiovascular disease, tuberculosis, and cancer. Nanoprecipitation is a commonly used method to synthesize LPHN in a low cost manner. However, this multi-step process proves to be difficult in consistently producing uniformly sized nanoparticles. Here we developed a microfluidic device that utilizes a three-channel pathway and mixer channel to synthesize uniformly sized LPHN in a controlled manner. Dynamic light scattering results of the microfluidic synthesized nanoparticles show decrease in diameter size from 140 nm to 40 nm as the Reynolds number of the channel inflow increases. Transmission electron microscopy confirms the size and morphology of the nanoparticles. Three dimensional structure of the LPHN were observed using atomic force microscopy. The production of higher quality nanoparticles using our microfluidics device can expedite the research and development process of drug delivering lipid polymer nanoparticles.


2018 ◽  
Vol 74 (2) ◽  
pp. 212-217 ◽  
Author(s):  
Shu-Ying Han ◽  
Xue Niu ◽  
Jia Wang ◽  
Guo-Xia Jin ◽  
Ai Liu ◽  
...  

A polydentate ligand bridged by a fluorene group, namely 9,9-bis(2-hydroxyethyl)-2,7-bis(pyridin-4-yl)fluorene (L), has been prepared under solvothermal conditions in acetonitrile. Crystals of the three-dimensional metal–organic framework (MOF) poly[[[μ3-9,9-bis(2-hydroxyethyl)-2,7-bis(pyridin-4-yl)fluorene-κ3 N:N′:O]bis(methanol-κO)(μ-sulfato-κ2 O:O′)nickel(II)] methanol disolvate], {[Ni(SO4)(C27H24N2O2)(CH3OH)]·2CH3OH} n , (I), were obtained by the solvothermal reaction of L and NiSO4 in methanol. The ligand L forms a two-dimensional network in the crystallographic bc plane via two groups of O—H...N hydrogen bonds and neighbouring two-dimensional planes are completely parallel and stack to form a three-dimensional structure. In (I), the NiII ions are linked by sulfate ions through Ni—O bonds to form inorganic chains and these Ni-containing chains are linked into a three-dimensional framework via Ni—O and Ni—N bonds involving the polydentate ligand L. With one of the hydroxy groups of L coordinating to the NiII atom, the torsion angle of the hydroxyethyl group changes from that of the uncoordinated molecule. In addition, the adsorption properties of (I) with carbon dioxide were investigated.


Author(s):  
Matjaz Mazaj ◽  
Venceslav Kaucic ◽  
Amalija Golobic ◽  
Natasa Zabukovec Logar

A new layered Ca–succinate coordination polymer, poly[μ3-succinato-calcium(II)], [Ca(C4H5O4)]n, was synthesized by reaction of CaCl2·2H2O and succinic acid in an aqueous medium under hydrothermal microwave conditions. The structure contains infinite layers of edge-sharing calcium pentagonal–bipyramidal polyhedra forming six-membered rings connected through succinate ligands. Such an assembly of inorganic building units is unique for calcium metal–organic framework-type structures. Adjacent layers are packed into a final pseudo-three-dimensional structure through weak C—H...O hydrogen bonds.


Author(s):  
Mayokun J. Ayodele ◽  
Travis C. Green ◽  
W. A. Chathuri V. Warsapperuma ◽  
Malcolm D. E. Forbes ◽  
Alexis D. Ostrowski

The title compound, [Cu2(C19H23N7O)(C2H3O2)4] n , was obtained via reaction of copper(II) acetate with the coordinating ligand, 6-ethoxy-N 2,N 4-bis[2-(pyridin-2-yl)ethyl]-1,3,5-triazine-2,4-diamine. The crystallized product adopts the monoclinic P21/c space group. The metal core exhibits a paddle-wheel structure typical for dicopper tetraacetate units, with triazine and pyridyl nitrogen atoms from different ligands coordinating to the two axial positions of the paddle wheel in an asymmetric manner. This forms a coordination polymer with the segments of the polymer created by the c-glide of the P21/c setting of the space group. The resulting chains running along the c-axis direction are held together by intramolecular N—H...O hydrogen bonding. These chains are further packed by dispersion forces, producing an extended three-dimensional structure.


Author(s):  
Barbara Modec

Single crystals of a triclinic polymorphic form ofmer-μ-oxalato-bis[chloridotripyridinecobalt(II)] pyridine disolvate, [Co2(C2O4)Cl2(C5H5N)6]·2C5H5N, have been prepared by solvothermal methods. The structure and geometric parameters strongly resemble those of the previously reported monoclinic polymorph [Bolte (2006).Acta Cryst.E62, m597–m598]. In both polymorphic forms, the dinuclear complex molecules are located on a crystallographic centre of inversion, with the CoIIcations in a distorted octahedral environment consisting of a chloride ligand, three pyridine ligands and a chelating bis-bidentate oxalate ligand. This last serves as a bridging ligand between two CoIIcations. The polymorphs differ in the mutual orientation of their pyridine ligands in the dinuclear molecules and in their intermolecular connectivity. In the triclinic polymorph, C—H...O, C—H...Cl, C—H...π and π–π interactions link the dinuclear molecules into a three-dimensional structure. Pyridine solvent molecules are attached to this structureviaweak interactions.


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