New One-Dimensional Commensurate and Incommensurate Structural Forms of Sr-Co Oxide

1996 ◽  
Vol 453 ◽  
Author(s):  
R. Christoffersen ◽  
A. J. Jacobson ◽  
S. L. Hegwood ◽  
L. Liu
Keyword(s):  
Mixed Layer ◽  
Excess Oxygen ◽  
Slow Cooling ◽  
One Dimensional ◽  
Vacancy Ordering ◽  
Structural Modulation ◽  
Hexagonal Perovskites ◽  
Trigonal Prismatic ◽  
Oxygen Atoms

AbstractNew forms of Sr-Co oxide with one-dimensional structures related to mixed-layer hexagonal perovskites have been synthesized and characterized by TEM. Crystals of Sr5Co2O12 grown from molten KOH flux and oxidized under slow cooling have structures based on a 3/2 ratio of mixed [Sr3CoO6] and [Sr3O9] layers. This is the first known structure with layers of this type stacked in a non-integer ratio, yielding chains of face-sharing octahedral and trigonal prismatic Co-sites with a 3 + 1 sequence along the c-axis. In oxygen-deficient Sr5Co2O12−x, the {110} structural modulation of the stoichiometric 5:4 phase becomes rotated to an irrational orientation, possibly in association with vacancy ordering, forming an incommensurate superstructure. For the compound Sr6Co5O15, previously known to have a 1/1 ratio of [Sr3CoO6] and [Sr3O9] layers with a 4 + 1 octahedral/trigonal prismatic site sequence, introduction of excess oxygen atoms leads to formation of a commensurate rhombohedral superlattice in which c is doubled relative to the stoichiometric 6:5 phase.

scholarly journals Crystal structure of the BaII-based CoII-containing one-dimensional coordination polymer poly[[aqua{μ4-2,2′-[(4,10-dimethyl-1,4,7,10-tetraazacyclododecane-1,7-diyl)bis(methylidene)]bis(4-oxo-4H-pyran-3-olato)}perchloratocobaltbarium] perchlorate]

2017 ◽  
Vol 73 (12) ◽  
pp. 1806-1811 ◽  
Author(s):  
Paola Paoli ◽  
Eleonora Macedi ◽  
Patrizia Rossi ◽  
Luca Giorgi ◽  
Mauro Formica ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Coordination Polymer ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Title Compound ◽  
Macrocyclic Ligand ◽  
Asymmetric Unit ◽  
One Dimensional ◽  
Trigonal Prismatic ◽  
Oxygen Atoms

The title compound, {[Ba{Co(H-2L1)}(ClO4)(H2O)]ClO4}n,L1 =4,10-bis[(3-hydroxy-4-pyron-2-yl)methyl]-1,7-dimethyl-1,4,7,10-tetraazacyclododecane, is a one-dimensional coordination polymer. The asymmetric unit consists of a {Ba[Co(H–2L1)](ClO4)(H2O)}+cationic fragment and a non-coordinating ClO4−anion. In the neutral [Co(H–2L1)] moiety, the cobalt ion is hexacoordinated in a trigonal–prismatic fashion by the surrounding N4O2donor set. The Ba2+ion is nine-coordinated and exhibits a distorted [BaO9] monocapped square-antiprismatic geometry, the six oxygen atoms coming from three distinct [Co(H–2L1)] moieties, while the remaining three vertices are occupied by the oxygen atoms of a bidentate perchlorate anion and a water molecule. A barium–μ2-oxygen motif develops along theaaxis, connecting symmetry-related dinuclear BaII–CoIIcationic fragments in a wave-like chain, forming a one-dimensional metal coordination polymer. Non-coordinating ClO4−anions are located in the space between the chains. Weak C—H...O hydrogen bonds involving both coordinating and non-coordinating perchlorate anions build the whole crystal architecture. To our knowledge, this is the first example of a macrocyclic ligand forming a BaII-based one-dimensional coordination polymer, containing CoIIions surrounded by a N4O2donor set.

On the numerical study of thermohydrodynamics and biochemistry of inland water bodies

2021 ◽  
Author(s):  
Daria Gladskikh ◽  
Evgeny Mortikov ◽  
Victor Stepanenko
Keyword(s):  
Mixed Layer ◽  
Numerical Study ◽  
Three Dimensional ◽  
Water Bodies ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
One Dimensional ◽  
Lake Model ◽  
Upper Mixed Layer ◽  
The One

<p>The study of thermodynamic and biochemical processes of inland water objects using one- and three-dimensional RANS numerical models was carried out both for idealized water bodies and using measurements data. The need to take into account seiche oscillations to correctly reproduce the deepening of the upper mixed layer in one-dimensional (vertical) models is demonstrated. We considered the one-dimensional LAKE model [1] and the three-dimensional model [2, 3, 4] developed at the Research Computing Center of Moscow State University on the basis of a hydrodynamic code combining DNS/LES/RANS approaches for calculating geophysical turbulent flows. The three-dimensional model was supplemented by the equations for calculating biochemical substances by analogy with the one-dimensional biochemistry equations used in the LAKE model. The effect of mixing processes on the distribution of concentration of greenhouse gases, in particular, methane and oxygen, was studied.</p><p>The work was supported by grants of the RF President’s Grant for Young Scientists (MK-1867.2020.5, MD-1850.2020.5) and by the RFBR (19-05-00249, 20-05-00776). </p><p>1. Stepanenko V., Mammarella I., Ojala A., Miettinen H., Lykosov V., Timo V. LAKE 2.0: a model for temperature, methane, carbon dioxide and oxygen dynamics in lakes // Geoscientific Model Development. 2016. V. 9(5). P. 1977–2006.<br>2. Mortikov E.V., Glazunov A.V., Lykosov V.N. Numerical study of plane Couette flow: turbulence statistics and the structure of pressure-strain correlations // Russian Journal of Numerical Analysis and Mathematical Modelling. 2019. 34(2). P. 119-132.<br>3. Mortikov, E.V. Numerical simulation of the motion of an ice keel in stratified flow // Izv. Atmos. Ocean. Phys. 2016. V. 52. P. 108-115.<br>4. Gladskikh D.S., Stepanenko V.M., Mortikov E.V. On the influence of the horizontal dimensions of inland waters on the thickness of the upper mixed layer // Water Resourses. 2021.V. 45, 9 pages. (in press) </p>

Structural Systematics of 2/4-Nitrophenoxide Complexes of Closed-Shell Metal Ions. VI 4-Nitrophenoxides of Group 2

1998 ◽  
Vol 51 (8) ◽  
pp. 775 ◽  
Author(s):  
Jack M. Harrowfield ◽  
Raj Pal Sharma ◽  
Brian W. Skelton ◽  
Paloth Venugopalam ◽  
Allan H. White
Keyword(s):  
Metal Ions ◽  
Closed Shell ◽  
Water Molecules ◽  
One Dimensional ◽  
Phenolic Oxygen ◽  
C 23 ◽  
Structure Determinations ◽  
Group 2 ◽  
Coordinated Water ◽  
Oxygen Atoms

Room-temperature single-crystal X-ray structure determinations are recorded for 4-nitrophenolate (4-np-) salts of Group 2 metal ions, variously hydrated, M(4-np)2.xH2O, M = Mg, Ca, Sr, Ba. Mg(4-np)2.8H2 O is monoclinic, P21/c, a 12·402(3), b 6·673(7), c 11·833(6) Å, β 93·70(3)°, Z = 2; conventional R on |F| was 0·041 for No 1995 independent ‘observed’ (I > 3σ(I)) reflections. Ca(4-np)2.4H2O is monoclinic, P21/c, a 13·109(8), b 3·644(1), c 21·181(8) Å, β 125·55(3)°, Z= 2, R 0·050 for No 1371. Sr(4-np)2.8H2O is monoclinic, P21/n, a 7·934(1), b 10·658(1), c 23·602(2) Å, β 91·36(1)°, Z = 4, R 0·038 for No 2050. Ba(4-np)2.8H2O is monoclinic P21/c, a 15·990(8), b 6·337(3), c 25·634(8) Å, β 126·1(3)°, Z = 4, R 0·021 for No 3115. The magnesium salt is ionic with [Mg(OH2)6]2+ cations and interleaved anion stacks up b. The calcium salt is a one-dimensional polymer with ... Ca(µ-O)2Ca(µ-O)2Ca ... spine, the bridges being phenolic oxygen atoms.trans-Coordinated water molecules make up six-coordination about the calcium, the anion planes stacking at the b spacing. The strontium adduct is also a one-dimensional polymer with a similar spine, but with water molecule oxygen atoms bridging, the nine-coordinate strontium environment being made up by a chelating nitro group and three unidentate water molecules. Coordinated anions stacked up a are interleaved by free anions. The barium salt is simply [Ba(4-np)(OH2)8]+ (4-np-), the ligand anion (semi)chelated through the nitro pair of oxygen atoms, again with interleaving anion/ligand stacking.

Electron Microscopy of a Family of Hexagonal Perovskites: One-Dimensional Structures Related to Sr4Ni3O9

1998 ◽  
Vol 135 (1) ◽  
pp. 1-16 ◽  
Author(s):  
M. Huvé ◽  
C. Renard ◽  
F. Abraham ◽  
G. Van Tendeloo ◽  
S. Amelinckx
Keyword(s):  
Electron Microscopy ◽  
One Dimensional ◽  
Hexagonal Perovskites

ChemInform Abstract: Sr3PbNiO6: Trigonal Prismatic Lead in a Novel Inverse K4CdCl6-Type Pseudo-One-Dimensional Oxide.

ChemInform ◽  
2010 ◽  
Vol 31 (2) ◽  
pp. no-no
Author(s):  
Mark D. Smith ◽  
Judith K. Stalick ◽  
Hans-Conrad zur Loye
Keyword(s):  
One Dimensional ◽  
Trigonal Prismatic

scholarly journals A One-Dimensional Mixed Layer Ocean Model for Use in Three-Dimensional Climate Simulations: Control Simulation Compared to Observations

2005 ◽  
Vol 18 (13) ◽  
pp. 2199-2221 ◽  
Author(s):  
Monica Y. Stephens ◽  
Robert J. Oglesby ◽  
Martin Maxey
Keyword(s):  
Heat Flux ◽  
Mixed Layer ◽  
General Circulation ◽  
Climate Model ◽  
Mixed Layer Depth ◽  
Circulation Model ◽  
Ocean Model ◽  
Ocean Dynamics ◽  
One Dimensional ◽  
Mixed Layer Ocean

Abstract A study has been made of the dynamic interactions between the surface layer of the ocean and the atmosphere using a climate model that contains a new approach to predicting the sea surface temperature (SST). The atmospheric conditions are simulated numerically with the NCAR Community Climate Model (CCM3). The SST is determined by a modified Kraus–Turner-type one-dimensional mixed layer ocean model (MLOM) for the upper ocean that has been coupled to CCM3. The MLOM simulates vertical ocean dynamics and demonstrates the effects of the seasonal variation of mixed layer depth and convective instability on the SST. A purely thermodynamic slab ocean model (SOM) is currently available for use with CCM3 to predict the SST. A large-scale ocean general circulation model (OGCM) may also be coupled to CCM3; however, the OGCM is computationally intensive and is therefore not a good tool for conducting multiple sensitivity studies. The MLOM provides an alternative to the SOM that contains seasonally and spatially specified mixed layer depths. The SOM also contains a heat flux correction called Q-flux that crudely accounts for ocean heat transport by artificially specifying a heat flux that forces the SOM to replicate the observed SST. The results of the coupled MLOM–CCM3 reveal that the MLOM may be used on a global scale and can therefore replace the standard coupled SOM–CCM3 that contains no explicit ocean dynamics. Additionally, stand-alone experiments of the MLOM that are forced with realistic winds, heat, and moisture fluxes show that the MLOM closely approximates the observed seasonal cycle of SST.

A novel three-dimensional CdIIcoordination polymer: poly[[aquabis(2,2′-bipyridine)(μ5-pyrazol-1-ide-3,5-dicarboxylato)(μ4-pyrazol-1-ide-3,5-dicarboxylato)(μ3-pyrazole-3,5-dicarboxylato)tetracadmium(II)] dihydrate]

2012 ◽  
Vol 68 (3) ◽  
pp. m76-m79
Author(s):  
Chunhua Fan ◽  
Yanfeng Yue ◽  
Zhengliang Lu
Keyword(s):  
Dicarboxylic Acid ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
One Dimensional ◽  
Coordination Numbers ◽  
Distorted Octahedral ◽  
Anionic Ligands ◽  
Coordination Framework ◽  
Coordinated Water ◽  
Trigonal Prismatic

The title compound, {[Cd4(C5H2N2O4)(C5HN2O4)2(C10H8N2)2(H2O)]·2H2O}n, crystallized in the monoclinic space groupP21/nand displays a three-dimensional architecture. The asymmetric unit is composed of four crystallographically independent CdIIcentres, two triply deprotonated pyrazole-3,5-dicarboxylic acid molecules, one doubly deprotonated pyrazole-3,5-dicarboxylic acid molecule, two 2,2′-bipyridine ligands, one coordinated water molecule and two interstitial water molecules. Interestingly, the CdIIcenters exhibit two different coordination numbers. Two CdIIcentres adopt a distorted octahedral arrangement and a third a trigonal–prismatic geometry, though they are all hexacoordinated. However, the fourth CdIIcenter is heptacoordinated and displays a pentagonal–bipyramidal geometry. The three anionic ligands adopt μ3-, μ4- and μ5-bridging modes, first linking CdIIcenters into a one-dimensional wave-like band, then into a wave-like layer and finally into a three-dimensional coordination framework, which is stabilized by hydrogen bonds.

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