Self-assembly and X-ray structure of a ten-component, three-dimensional metallosupramolecular cage

1997 ◽  
pp. 541-542 ◽  
Author(s):  
Chris M. Hartshorn ◽  
Peter J. Steel
Keyword(s):  
Self Assembly ◽  
Three Dimensional ◽  
X Ray

Construction of a three-dimensional supramolecular framework based on an anionic cadmium(II) coordination network and protonated dipyridine organic cations

2018 ◽  
Vol 74 (8) ◽  
pp. 889-893
Author(s):  
Qian-Kun Zhou ◽  
Lin Wang ◽  
Dong Liu
Keyword(s):  
Hydrogen Bonding ◽  
Self Assembly ◽  
Title Compound ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
X Ray ◽  
Coordination Network ◽  
Hydrogen Bonding Interactions ◽  
Point Symbol

As a class of multifunctional materials, crystalline supramolecular complexes have attracted much attention because of their unique architectures, intriguing topologies and potential applications. In this article, a new supramolecular compound, namely catena-poly[4,4′-(buta-1,3-diene-1,4-diyl)dipyridin-1-ium [(μ4-benzene-1,2,4,5-tetracarboxylato-κ6 O 1,O 1′:O 2:O 4,O 4′:O 5)cadmium(II)]], {(C14H14N2)[Cd(C10H2O8)]} n or {(1,4-H2bpbd)[Cd(1,2,4,5-btc)]} n , has been prepared by the self-assembly of Cd(NO3)2·4H2O, benzene-1,2,4,5-tetracarboxylic acid (1,2,4,5-H4btc) and 1,4-bis(pyridin-4-yl)buta-1,3-diene (1,4-bpbd) under hydrothermal conditions. The title compound has been structurally characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. Each CdII centre is coordinated by six O atoms from four different (1,2,4,5-btc)4− tetraanions. Each CdII cation, located on a site of twofold symmetry, binds to four carboxylate groups belonging to four separate (1,2,4,5-btc)4− ligands. Each (1,2,4,5-btc)4− anion, situated on a position of \overline{1} symmetry, binds to four crystallographically equivalent CdII centres. Neighbouring CdII cations interconnect bridging (1,2,4,5-btc)4− anions to form a three-dimensional {[Cd(1,2,4,5-btc)]2−} n anionic coordination network with infinite tubular channels. The channels are visible in both the [1\overline{1}0] and the [001] direction. Such a coordination network can be simplified as a (4,4)-connected framework with the point symbol (4284)(4284). To balance the negative charge of the metal–carboxylate coordination network, the cavities of the network are occupied by protonated (1,4-H2bpbd)2+ cations that are located on sites of twofold symmetry. In the crystal, there are strong hydrogen-bonding interactions between the anionic coordination network and the (1,4-H2bpbd)2+ cations. Considering the hydrogen-bonding interactions, the structure can be further regarded as a three-dimensional (4,6)-connected supramolecular architecture with the point symbol (4264)(42687·84). The thermal stability and photoluminescence properties of the title compound have been investigated.

Collagen: the organic matrix of bone

1984 ◽  
Vol 304 (1121) ◽  
pp. 455-477 ◽  
Keyword(s):  
Self Assembly ◽  
Hexagonal Lattice ◽  
Three Dimensional ◽  
Organic Matrix ◽  
Calcium Hydroxyapatite ◽  
Collagen Molecule ◽  
Crystalline Region ◽  
X Ray ◽  
Molecular Arrangement ◽  
Diffraction Patterns

Collagen is the principal organic matrix in bone. The triple helical region of the molecule is 1014 amino acids long. In fibrils these molecules are staggered axially by integers of 234 residues or 68 nm ( D ). This axial shift occurs by self-assembly and can be understood in terms of a periodicity in the occurrence of apolar and polar residues in the amino acid sequence. Because the molecular length L = 4.47 D , there are gaps 1.5 x 36.5 nm regularly arrayed throughout the fibrils. The three-dimensional molecular arrangement is a quasi-hexagonal lattice with three distinct values for the principal interplanar spacings. Analysis of the intensity distribution in the medium-angle X -ray diffraction patterns from tendons has produced the following picture of the molecular arrangement in fibrils (Fraser et al . 1983). The molecular helices have a coherent length of 32 nm and are tilted parallel to a specific place within the lattice. A regular azimuthal interaction exists between these helices. This crystalline region could be the overlap region with a non-crystalline gap region. However, the gap is still regular axially and the molecular helices retain their structure; their lateral packing is perturbed although they retain a ‘gap’. Neutron and X -ray scattering experiments have shown that calcium hydroxyapatite crystals occur in the gap and are nucleated at a specific though unknown location within the gap. The c -axis of the apatite crystals is parallel to the fibril axis and its length c = 0.688 nm is close to the axial periodicity in a protein with an extended β-conformation. If the telopeptides at the end of a collagen molecule do have this conformation they would either have a highly heterogeneous conformation or exist in a folded manner because the overall length of the telopeptides is shorter than a regular collagen repeat of 0.029 nm would allow.

X-ray characterization of contact holes for block copolymer lithography

2019 ◽  
Vol 52 (1) ◽  
pp. 106-114
Author(s):  
Daniel F. Sunday ◽  
Florian Delachat ◽  
Ahmed Gharbi ◽  
Guillaume Freychet ◽  
Christopher D. Liman ◽  
...  
Keyword(s):  
Self Assembly ◽  
Low Cost ◽  
Ion Beam ◽  
Three Dimensional ◽  
Incident Beam ◽  
Residual Layer ◽  
Processing Conditions ◽  
Dimensional Metrology ◽  
Grid Pattern ◽  
X Ray

The directed self-assembly (DSA) of block copolymers (BCPs) is a promising low-cost approach to patterning structures with critical dimensions (CDs) which are smaller than can be achieved by traditional photolithography. The CD of contact holes can be reduced by assembling a cylindrical BCP inside a patterned template and utilizing the native size of the cylinder to dictate the reduced dimensions of the hole. This is a particularly promising application of the DSA technique, but in order for this technology to be realized there is a need for three-dimensional metrology of the internal structure of the patterned BCP in order to understand how template properties and processing conditions impact BCP assembly. This is a particularly challenging problem for traditional metrologies owing to the three-dimensional nature of the structure and the buried features. By utilizing small-angle X-ray scattering and changing the angle between the incident beam and sample we can reconstruct the three-dimensional shape profile of the empty template and the residual polymer after self-assembly and removal of one of the phases. A two-dimensional square grid pattern of the holes results in scattering in both in-plane directions, which is simplified by converting to a radial geometry. The shape is then determined by simulating the scattering from a model and iterating that model until the simulated and experimental scattering profiles show a satisfactory match. Samples with two different processing conditions are characterized in order to demonstrate the ability of the technique to evaluate critical features such as residual layer thickness and sidewall height. It was found that the samples had residual layer thicknesses of 15.9 ± 3.2 nm and 4.5 ± 2.2 nm, which were clearly distinguished between the two different DSA processes and in good agreement with focused ion beam scanning transmission electron microscopy (FIBSTEM) observations. The advantage of the X-ray measurements is that FIBSTEM characterizes around ten holes, while there are of the order of 800 000 holes illuminated by the X-ray beam.

Two new isostructural mercury(II) complexes involving the N-heterocyclic 1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole ligand: syntheses, structures and properties

2017 ◽  
Vol 73 (4) ◽  
pp. 314-318 ◽  
Author(s):  
Xu Wei ◽  
Jian-Hua Li ◽  
Qiu-Ying Huang ◽  
Xiang-Ru Meng
Keyword(s):  
Solid State ◽  
Hydrogen Bonds ◽  
Ir Spectra ◽  
Self Assembly ◽  
Three Dimensional ◽  
The Self ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heterocyclic Ligand ◽  
Structures And Properties

The unsymmetrical N-heterocyclic ligand 1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole (bmi) has three potential N-atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1-[(benzotriazol-1-yl)methyl]-1H-1,3-imidazole-κN3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self-assembly of bmi with HgBr2or HgI2. Single-crystal X-ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgIIions in monodentate modes. In the solid state, both complexes display three-dimensional networks formed by a combination of hydrogen bonds and π–π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded.

Assembly of a Flexible 2,2ʹ-Oxydibenzoate and Silver(I) Ions to a Novel 3D Supramolecular Framework: Syntheses, Structure and Properties

2012 ◽  
Vol 67 (11) ◽  
pp. 1191-1196 ◽  
Author(s):  
Chong-Zhen Mei ◽  
Kai-Hui Li ◽  
Hai-Hua Li
Keyword(s):  
Hydrogen Bonding ◽  
Elemental Analysis ◽  
Self Assembly ◽  
Three Dimensional ◽  
Stacking Interactions ◽  
Supramolecular Architecture ◽  
Supramolecular Framework ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
X Ray

Self-assembly of silver(I) cations, flexible 2,2ʹ-oxydibenzoate anions (L2-), and 1,2-bis(4- pyridyl)ethane (bpa) ligands affords a new three-dimensional supramolecular architecture, {[Ag2(L)(bpa)2]⋅(H2O)4}n (1), which has been characterized by elemental analysis, IR, TGA, PXRD, and single-crystal X-ray diffraction. Complex 1exhibits layers further connected through hydrogen bonding and π...π stacking interactions. Its photoluminescence was also investigated.

scholarly journals Self-Assembly of Antiferromagnetically-Coupled Copper(II) Supramolecular Architectures with Diverse Structural Complexities

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5549 ◽  
Author(s):  
Santokh S. Tandon ◽  
Scott D. Bunge ◽  
Neil Patel ◽  
Esther C. Wang ◽  
Laurence K. Thompson
Keyword(s):  
Schiff Base ◽  
Self Assembly ◽  
Three Dimensional ◽  
The Self ◽  
Basic Building Block ◽  
Schiff Base Ligands ◽  
X Ray ◽  
Supramolecular Architectures ◽  
Hydroxy Groups ◽  
New Discovery

The self-assembly of 2,6-diformyl-4-methylphenol (DFMP) and 1-amino-2-propanol (AP)/2-amino-1,3-propanediol (APD) in the presence of copper(II) ions results in the formation of six new supramolecular architectures containing two versatile double Schiff base ligands (H3L and H5L1) with one-, two-, or three-dimensional structures involving diverse nuclearities: tetranuclear [Cu4(HL2−)2(N3)4]·4CH3OH·56H2O (1) and [Cu4(L3−)2(OH)2(H2O)2] (2), dinuclear [Cu2(H3L12−)(N3)(H2O)(NO3)] (3), polynuclear {[Cu2(H3L12−)(H2O)(BF4)(N3)]·H2O}n (4), heptanuclear [Cu7(H3L12−)2(O)2(C6H5CO2)6]·6CH3OH·44H2O (5), and decanuclear [Cu10(H3L12−)4(O)2(OH)2(C6H5CO2)4] (C6H5CO2)2·20H2O (6). X-ray studies have revealed that the basic building block in 1, 3, and 4 is comprised of two copper centers bridged through one μ-phenolate oxygen atom from HL2− or H3L12−, and one μ-1,1-azido (N3−) ion and in 2, 5, and 6 by μ-phenoxide oxygen of L3− or H3L12− and μ-O2− or μ3-O2− ions. H-bonding involving coordinated/uncoordinated hydroxy groups of the ligands generates fascinating supramolecular architectures with 1D-single chains (1 and 6), 2D-sheets (3), and 3D-structures (4). In 5, benzoate ions display four different coordination modes, which, in our opinion, is unprecedented and constitutes a new discovery. In 1, 3, and 5, Cu(II) ions in [Cu2] units are antiferromagnetically coupled, with J ranging from −177 to −278 cm−1.

Structure of the collagen fibril: some variations on a theme of tetragonally packed dimers

1980 ◽  
Vol 209 (1175) ◽  
pp. 275-297 ◽  
Keyword(s):  
Self Assembly ◽  
Collagen Fibril ◽  
Three Dimensional ◽  
Local Property ◽  
Square Lattice ◽  
Dimensional Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Variations On A Theme ◽  
Overlap Region

A theory of the three-dimensional structure of the collagen fibril outlined by Woodhead-Galloway (1977) is discussed in greater detail and an account of the low angle X-ray diffraction pattern (Miller & Wray 1971) is obtained. Square-packed dimers form the overlap region of the fibril. In the gap region, clusters of four dimers at each of the points of a square lattice of side 3.8 nm provide the structure. Molecules are parallel to the axis of the fibril in the overlap region and tilted from the axis by a few degrees in the gap region. A brief discussion of some aspects of the self assembly of such a structure is included. In particular, it is noted that the axially projected D ( ═ 66.8 nm) period, which is a property of the Whole fibril, is not necessarily also a local property; there may be no well defined and finite small grouping of molecules that is itself D -periodic, such as is proposed in the microfibril model of the fibril (Smith 1968). On the other hand, there is strong circumstantial evidence of a D -periodic crystallographic unit cell.

Syntheses, Structures and Electrochemical Properties of Two New Copper(II) Complexes Based on Isomeric Bis(pyridylformyl)piperazine Ligands and Rigid=Flexible Organic Dicarboxylates

2013 ◽  
Vol 68 (2) ◽  
pp. 138-146 ◽  
Author(s):  
Hong-Yan Lin ◽  
Peng Liu ◽  
Xiu-Li Wang ◽  
Chuang Xu ◽  
Guo-Cheng Liu
Keyword(s):  
Electrochemical Properties ◽  
Self Assembly ◽  
Three Dimensional ◽  
Supramolecular Network ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
Pyridyl Nitrogen ◽  
X Ray ◽  
Network Complex ◽  
Polymeric Framework

Two new copper(II) complexes, [Cu2(3-bpfp)(2,6-PDA)2(H2O)2] (1) and [Cu(4-bpfp)0:5 (glu)]·H2O (2), have been hydrothermally synthesized by self-assembly of isomeric bis(pyridylformyl)piperazine ligands [3-bpfp=bis(3-pyridylformyl)piperazine, 4-bpfp=bis(4- pyridylformyl)piperazine], rigid pyridine-2,6-dicarboxylic acid (2,6-H2PDA) or flexible glutaric acid (H2glu), and copper(II) chloride. Single-crystal X-ray diffraction analysis reveals that two adjacent CuII ions are connected by the 3-bpfp ligand to build a dinuclear unit in complex 1, in which 2,6-PDA serves as a terminal chelating ligand. Adjacent dinuclear units are further linked by hydrogen bonding and π-π stacking interactions to form a three-dimensional (3D) supramolecular network. Complex 2 is a 3D coordination polymeric framework based on a layer polymer [Cu(glu)]n and bridging 4-bpfp ligands with 6-connected (44.610.8) topology. In 1 and 2, the ligands 3-bpfp and 4-bpfp adopt a μ2-bridging coordination mode (via ligation of pyridyl nitrogen atoms). The thermal stability and the electrochemical properties of the title complexes have been studied.

Construction and photoluminescence properties of a three-dimensional ZnII coordination network based on naphthalene-1,4-dicarboxylic acid and 1,6-bis(pyridin-3-yl)-1,3,5-hexatriene

2018 ◽  
Vol 74 (9) ◽  
pp. 1053-1057 ◽  
Author(s):  
Qian-Kun Zhou ◽  
Lin Wang ◽  
Yun Xu ◽  
Ni-Ya Li
Keyword(s):  
Dicarboxylic Acid ◽  
Self Assembly ◽  
Three Dimensional ◽  
Square Lattice ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
X Ray ◽  
Pyridyl Ligands ◽  
Connected Node

In recent years, coordination polymers constructed from multidentate carboxylate and pyridyl ligands have attracted much attention because these ligands can adopt a rich variety of coordination modes and thus lead to the formation of crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[μ2-1,6-bis(pyridin-3-yl)-1,3,5-hexatriene-κ2 N:N′](μ3-naphthalene-1,4-dicarboxylato-κ4 O 1,O 1′:O 4:O 4′)zinc(II)], [Zn(C12H6O4)(C16H14N2)] n , has been prepared by the self-assembly of Zn(NO3)2·6H2O, naphthalene-1,4-dicarboxylic acid (1,4-H2ndc) and 1,6-bis(pyridin-3-yl)-1,3,5-hexatriene (3,3′-bphte) under hydrothermal conditions. The title compound has been structurally characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. Each ZnII ion is six-coordinated by four O atoms from three 1,4-ndc2− ligands and by two N atoms from two 3,3′-bphte ligands, forming a distorted octahedral ZnO4N2 coordination geometry. Pairs of ZnII ions are linked by 1,4-ndc2− ligands, leading to the formation of a two-dimensional square lattice (sql) layer extending in the ab plane. In the crystal, adjacent layers are further connected by 3,3′-bphte bridges, generating a three-dimensional architecture. From a topological viewpoint, if each dinuclear zinc unit is considered as a 6-connected node and the 1,4-ndc2− and 3,3′-bphte ligands are regarded as linkers, the structure can be simplified as a unique three-dimensional 6-connected framework with the point symbol 446108. The thermal stability and solid-state photoluminescence properties have also been investigated.

scholarly journals Supramolecular Hydrogen Bonded 3D Molecular Self Assembly Constructed from [(Co (nicotinamide)2(thiocyanate)2(H2O)2] Complex Showing Anti-ferromagnetic Character

2014 ◽  
Vol 10 (6) ◽  
pp. 2864-2874
Author(s):  
Deepanjali Pandey ◽  
Shahid S.Narvi ◽  
Siddhartha Chaudhuri
Keyword(s):  
Self Assembly ◽  
Three Dimensional ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Spin Orbital ◽  
Space Group ◽  
X Ray ◽  
Susceptibility Data ◽  
Ferromagnetic Character ◽  
Hydrogen Bonded

A new three dimensional hydrogen bonded cobalt frame work from [Co(nicotinamide)2(thiocyanate)2(H2O)2] was synthesized and characterized by X-ray diffraction, magnetism ,TGA and IR spectroscopy. The compound crystallizes in Triclinic space group P-1 with a = 7.5475(19), b = 8.054(2), c =8.932(2). Alpha=73.347(4), beta=70.067(4), gamma=66.559(4) with space group P-1 Z = 1, 'C14 H16 N6 Co O4 S2', Mr =455.38, F(000) = 233 and μ(MoKα) =0.71073 mm-1. The final R = 0.0497 and wR = 0.1461 for 4185 observed reflections with I > 2σ(I) and R = 0.0721 and wR = 0.1619 for all data. X-ray diffraction analyses revealed that Co(1) is linked by the nicotinamide ligands to form the ladder shape along the c axis, which is further extended into two-dimensional networks via the joint of Co(2) along the a axis. Moreover, these two dimensional motifs are interconnected by the thiocyanate S...H bridges to form a complicated 3-D polymeric framework. The magnetic susceptibility data at 1000Oe external field in the temperature range 2-300 K obeys the Curie-Weiss law, giving θ = -24.12 K and C =2.43  thus indicating a dominant strong antiferromagnetic interaction and/or spin orbital coupling between the Co (II) ions. 

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