scholarly journals Heteronuclear Dirhodium-Gold Anionic Complexes: Polymeric Chains and Discrete Units

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1868
Author(s):  
Estefania Fernandez-Bartolome ◽  
Paula Cruz ◽  
Laura Abad Galán ◽  
Miguel Cortijo ◽  
Patricia Delgado-Martínez ◽  
...  
Keyword(s):  
Room Temperature ◽  
Silver Complexes ◽  
Metathesis Reaction ◽  
One Dimensional ◽  
Polymeric Chains ◽  
Polymeric Compounds ◽  
Anionic Complexes ◽  
The One ◽  
Silver Atoms

In this article, we report on the synthesis and characterization of the tetracarboxylatodirhodium(II) complexes [Rh2(μ–O2CCH2OMe)4(THF)2] (1) and [Rh2(μ–O2CC6H4–p–CMe3)4(OH2)2] (2) by metathesis reaction of [Rh2(μ–O2CMe)4] with the corresponding ligand acting also as the reaction solvent. The reaction of the corresponding tetracarboxylato precursor, [Rh2(μ–O2CR)4], with PPh4[Au(CN)2] at room temperature, yielded the one-dimensional polymers (PPh4)n[Rh2(μ–O2CR)4Au(CN)2]n (R = Me (3), CH2OMe (4), CH2OEt (5)) and the non-polymeric compounds (PPh4)2{Rh2(μ–O2CR)4[Au(CN)2]2} (R = CMe3 (6), C6H4–p–CMe3 (7)). The structural characterization of 1, 3·2CH2Cl2, 4·3CH2Cl2, 5, 6, and 7·2OCMe2 is also provided with a detailed description of their crystal structures and intermolecular interactions. The polymeric compounds 3·2CH2Cl2, 4·3CH2Cl2, and 5 show wavy chains with Rh–Au–Rh and Rh–N–C angles in the ranges 177.18°–178.69° and 163.0°–170.4°, respectively. A comparative study with related rhodium-silver complexes previously reported indicates no significant influence of the gold or silver atoms in the solid-state arrangement of these kinds of complexes.

A Note on Hidden Transient Chaos in the Lorenz System

2017 ◽  
Vol 18 (5) ◽  
pp. 427-434 ◽  
Author(s):  
Quan Yuan ◽  
Fang-Yan Yang ◽  
Lei Wang
Keyword(s):  
Rayleigh Number ◽  
Lorenz System ◽  
Critical Value ◽  
Transient Chaos ◽  
Topological Horseshoe ◽  
One Dimensional ◽  
Dynamical Behaviors ◽  
The Lorenz System ◽  
The One

AbstractIn this paper, the classic Lorenz system is revisited. Some dynamical behaviors are shown with the Rayleigh number $\rho $ somewhat smaller than the critical value 24.06 by studying the basins characterization of attraction of attractors and tracing the one-dimensional unstable manifold of the origin, indicating some interesting clues for detecting the existence of hidden transient chaos. In addition, horseshoes chaos is verified in the famous system for some parameters corresponding to the hidden transient chaos by the topological horseshoe theory.

scholarly journals Lipoarabinomannans: characterization of the multiacylated forms of the phosphatidyl-myo-inositol anchor by NMR spectroscopy

1999 ◽  
Vol 337 (3) ◽  
pp. 453-460 ◽  
Author(s):  
Jérôme NIGOU ◽  
Martine GILLERON ◽  
Germain PUZO
Keyword(s):  
Molecular Basis ◽  
Quantum Correlation ◽  
Analytical Approach ◽  
31P Nmr ◽  
Multiple Quantum ◽  
Double Negative ◽  
Bacillus Calmette Guerin ◽  
One Dimensional ◽  
The One

Lipoarabinomannans, which exhibit a large spectrum of immunological activities, emerge as the major antigens of mycobacterial envelopes. The lipoarabinomannan structure is based on a phosphatidyl-myo-inositol anchor whose integrity has been shown to be crucial for lipoarabinomannan biological activity and particularly for presentation to CD4/CD8 double-negative αβT cells by CD1 molecules. In this report, an analytical approach was developed for high-resolution 31P-NMR analysis of native, i.e. multiacylated, lipoarabinomannans. The one-dimensional 31P spectrum of cellular lipoarabinomannans, from Mycobacterium bovis Bacillus Calmette–Guérin, exhibited four 31P resonances typifying four types of lipoarabinomannans. Two-dimensional 1H-31P heteronuclear multiple-quantum-correlation/homonuclear Hartmann–Hahn analysis of the native molecules showed that these four types of lipoarabinomannan differed in the number and localization of fatty acids (from 1 to 4) esterifying the anchor. Besides the three acylation sites previously described, i.e. positions 1 and 2 of glycerol and 6 of the mannosyl unit linked to the C-2 of myo-inositol, we demonstrate the existence of a fourth acylation position at the C-3 of myo-inositol. We report here the first structural study of native multiacylated lipoarabinomannans, establishing the structure of the intact phosphatidyl-myo-inositol anchor. Our findings would help gain more understanding of the molecular basis of lipoarabinomannan discrimination in the binding process to CD1 molecules.

scholarly journals Solutions of the nonlinear paraxial equation due to laser plasma–interactions

2004 ◽  
Vol 22 (1) ◽  
pp. 69-74 ◽  
Author(s):  
F. OSMAN ◽  
R. BEECH ◽  
H. HORA
Keyword(s):  
Laser Plasma ◽  
Theoretical Study ◽  
Semiclassical Limit ◽  
General Setting ◽  
One Dimension ◽  
One Dimensional ◽  
Laser Plasma Interactions ◽  
Weak Limits ◽  
The One

This article presents a numerical and theoretical study of the generation and propagation of oscillation in the semiclassical limit ħ → 0 of the nonlinear paraxial equation. In a general setting of both dimension and nonlinearity, the essential differences between the “defocusing” and “focusing” cases are observed. Numerical comparisons of the oscillations are made between the linear (“free”) and the cubic (defocusing and focusing) cases in one dimension. The integrability of the one-dimensional cubic nonlinear paraxial equation is exploited to give a complete global characterization of the weak limits of the oscillations in the defocusing case.

scholarly journals Synthesis and Structural Characterization of a Series of One-Dimensional Heteronuclear Dirhodium-Silver Coordination Polymers

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 111 ◽  
Author(s):  
Paula Cruz ◽  
Estefania Fernandez-Bartolome ◽  
Miguel Cortijo ◽  
Patricia Delgado-Martínez ◽  
Rodrigo González-Prieto ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Coordination Polymers ◽  
Structural Characterization ◽  
Similar Reaction ◽  
Molecular Compound ◽  
Silver Complexes ◽  
One Dimensional ◽  
Wavy Structure ◽  
Solvent Molecules

Herein, we describe the preparation of heteronuclear dirhodium-silver complexes by reaction between molecular Rh(II)-Rh(II) compounds [Rh2(μ-O2CR)4L2] (R = Me, Ph (1), CH2OEt (2); L = solvent molecules) with paddlewheel structure and PPh4[Ag(CN)2]. One-dimensional coordination polymers of (PPh4)n[Rh2(μ-O2CR)4Ag(CN)2]n (R = Me (3), Ph (4), CH2OEt (5)) formula have been obtained by replacement of the two labile molecules in the axial positions of the paddlewheel structures by a [Ag(CN)2]− bridging unit. The crystal structures of 3–5 display a similar arrangement, having anionic chains with a wavy structure and bulky (PPh4)+ cations placed between the chains. The presence of the (PPh4)+ cations hinders the existence of intermolecular Ag-Ag interactions although several C-H····π interactions have been observed. A similar reaction between [Rh2(μ-O2CCMe3)4(HO2CCMe3)2] and PPh4[Ag(CN)2] led to the molecular compound (PPh4)2{Rh2(μ-O2CCMe3)4[Ag(CN)2]2} (6) by replacement of the axial HO2CCMe3 ligands by two [Ag(CN)2]− units. The trimethylacetate ligand increases the solubility of the complex during the crystallization favouring the formation of discrete heteronuclear species.

scholarly journals Observation of broad-band water waveguiding in shallow water: a revival

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Fabián Sepúlveda-Soto ◽  
Diego Guzmán-Silva ◽  
Edgardo Rosas ◽  
Rodrigo A. Vicencio ◽  
Claudio Falcón
Keyword(s):  
Shallow Water ◽  
Water Waves ◽  
Open Channel ◽  
Fluid Layer ◽  
Broad Band ◽  
Shallow Water Waves ◽  
One Dimensional ◽  
The One ◽  
Complex Phenomena

Abstract We report on the observation and characterization of broad-band waveguiding of surface gravity waves in an open channel, in the shallow water limit. The waveguide is constructed by changing locally the depth of the fluid layer, which creates conditions for surface waves to propagate along the generated guide. We present experimental and numerical results of this shallow water waveguiding, which can be straightforwardly matched to the one-dimensional water wave equation of shallow water waves. Our work revitalizes water waveguiding research as a relevant and controllable experimental setup to study complex phenomena using waveguide geometries.

Lewis-Base Adducts of Group 11 Metal(I) Compounds. LXXIV Synthesis and Structure of the 1 : 1 Adduct of Silver(I) Nitrate with Triphenylstibine

1997 ◽  
Vol 50 (6) ◽  
pp. 671 ◽  
Author(s):  
Effendy ◽  
John D. Kildea ◽  
Allan H. White
Keyword(s):  
Single Crystal ◽  
Structure Determination ◽  
Related Species ◽  
Room Temperature ◽  
Structural Data ◽  
Lewis Base ◽  
One Dimensional ◽  
X Ray ◽  
The One

The synthesis and room-temperature single-crystal X-ray structure determination of the 1 : 1 adduct of silver(I) nitrate with triphenylstibine, AgNO3/SbPh3 (1 : 1), is recorded, being monoclinic, Cc,a 12·824(2), b 15·794(4),c 9·796(2) Å, β 117·50(1)°, Z= 4; conventional R on F was 0·030 for 2881 independent ‘observed’ (I > 3σ(I)) reflections. The complex is a one-dimensional polymer with bridging nitrate groups, resembling in this respect its phosphine and arsine analogues. The completion of this study, along with related species recorded in accompanying papers, means that full structural data are now available for the complete array AgNO3/EPh3 (1 : n), E = P, As, Sb, n = 1–4, with the one exception of E = Sb, n = 2.

ESR Study of Electrochemically Doped Chalcogenide Nanotubes

2003 ◽  
Vol 775 ◽  
Author(s):  
Denis Arcon ◽  
Andrej Zorko ◽  
Pavel Cevc ◽  
Ales Mrzel ◽  
Maja Remskar ◽  
...  
Keyword(s):  
Room Temperature ◽  
Electrochemical Activity ◽  
Chain Model ◽  
Heisenberg Chain ◽  
One Dimensional ◽  
Narrow Component ◽  
Broad Component ◽  
X Band ◽  
Heavily Doped ◽  
The One

AbstractElectrochemical activity of differently pretreated single-wall subnanometer-diameter molybdenum disulfide tubes (nMoS2) was tested and compared with layered MoS2 material. In as prepared and de-iodized nMoS2 samples a significant increase in the charge capacity has been found compared to the one measured in dispersed nMoS2 or layered MoS2. Enhanced electrochemical activity has been attributed to a particular one-dimensional topology of nanotubes bundles. Electrochemically doped samples were then studied with X-band ESR. While undoped nMoS2 show no X-band ESR signal between room temperature and 4 K we found in heavily doped nMoS2 samples two distinct ESR components: a narrow component with a linewidth of few Guass and a broad component with a linewidth of more than 800 G. The broad ESR component is characteristic of Mo d-orbital-derived band. The temperature dependence of the ESR spin susceptibility and the linewidth of the broad ESR component can be discussed either in terms of conducting electrons coupled to defects or in terms of random-exchange Mo Heisenberg chain model.

High-pressure effect on the chain-like crystal structure of the semiconductors TlFeSe2 and TlFeS2

2015 ◽  
Vol 29 (08) ◽  
pp. 1550024 ◽  
Author(s):  
E. B. Asgerov ◽  
N. T. Dang ◽  
D. I. Ismayilov ◽  
S. E. Kichanov ◽  
R. N. Mehdiyeva ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Room Temperature ◽  
Structural Parameters ◽  
Monoclinic Crystal ◽  
One Dimensional ◽  
Monoclinic Crystal Structure ◽  
Anisotropic Lattice ◽  
The One ◽  
Lattice Compression

The crystal structure of the semiconductors TlFeSe 2 and TlFeS 2 has been studied by mean of neutron diffraction at room temperature and high pressure up to 4.2 GPa and 5.2 GPa, respectively. The chain-like monoclinic crystal structure with space group C2/m remains unchanged in both compounds in the entire pressure range. The anisotropic lattice compression and the large difference in the bulk modulus and the compressibility coefficients of the structural parameters of the two compounds have been observed. The mechanism of the observed phenomena was discussed. The enhancement of the one-dimensional antiferromagnetic and metallic character was predicted.

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