scholarly journals Structures of relevant ammonium salts in fertilizers

2010 ◽  
Vol 66 (3) ◽  
pp. 358-365 ◽  
Author(s):  
J. M. Montejo-Bernardo ◽  
S. García-Granda ◽  
A. Fernández-González
Keyword(s):  
Room Temperature ◽  
Rietveld Method ◽  
Structural Models ◽  
Ammonium Salts ◽  
Structure Packing ◽  
Double Salts ◽  
Ionic Distribution ◽  
Anions And Cations ◽  
State Ionic ◽  
Similar Crystal Structure

The crystal structures of two double salts of ammonium nitrate (AN) and ammonium sulfate (AS) are reported. The double salts 2NH4NO3·(NH4)2SO4 (2AN·AS) and 3NH4NO3·(NH4)2SO4 (3AN·AS) show a very similar crystal structure packing with alternating layers of anions and cations. The solid-state ionic distribution is controlled by an extensive hydrogen-bonding network with ammonium groups as the donors and O atoms acting as the acceptors. Crystallographic studies were conducted at both room temperature (293 K) and 100 K. Increasing the temperature involves shortening the b axis in the case of the 3AN·AS salt. Quantification of fertilizer mixtures using the Rietveld method was also carried out by means of the structural models reported in this paper for both salts.

Phase Transitions and Structures at 10, 92 and 293 K in Eight Trigonal Double Salts M I[M III(NH3)6](ClO4)2 X 2

1998 ◽  
Vol 54 (5) ◽  
pp. 613-625 ◽  
Author(s):  
B. N. Figgis ◽  
A. N. Sobolev ◽  
P. A. Reynolds
Keyword(s):  
Room Temperature ◽  
Ammonium Salts ◽  
Mirror Plane ◽  
X Ray Diffraction ◽  
Threefold Axis ◽  
Ionic Radii ◽  
X Ray ◽  
Double Salts ◽  
Unit Cells ◽  
Reversible Phase

The crystal structures of eight hexaammine-M III double salts have been determined by X-ray diffraction at 293 K, where M I, M III and X are NH4, Co, Cl (I), ammonium hexaamminecobalt(III) diperchlorate dichloride; Cs, Co, Cl (II), caesium hexaamminecobalt(III) diperchlorate dichloride; NH4, Ru, Cl (III), ammonium hexaammineruthenium(III) diperchlorate dichloride; K, Ru, Cl (IV), potassium hexaammineruthenium(III) diperchlorate dichloride; Rb, Ru, Cl (V), rubidium hexaammineruthenium(III) diperchlorate dichloride; Cs, Ru, Cl (VI), caesium hexaammineruthenium(III) diperchlorate dichloride; Cs, Cr, Cl (VII) caesium hexaamminechromium(III) diperchlorate dichloride; Cs, Cr, Br (VIII), caesium hexaamminechromium(III) diperchlorate dibromide. The structures of (I), (IV), (V) and (VI) have also been determined at 92 K and those of (V), (VII) and (VIII) at 10 K. At room temperature all are isomorphous, trigonal R3¯m, Z = 3, with only seven positional parameters for the seven unique non-H atoms. The ammine H atoms are disordered only in the Cs+ and NH_4^+ salts, and the NH_4^+ H atoms in the ammonium salts. At lower temperatures a reversible phase change is observed in all except the K+ member, by the lowering of symmetry to a twinned, but atomically ordered, R3¯ phase. In this R3¯ phase the hexaammine-M III and perchlorate ions have rotated about the threefold axis removing the former mirror plane in the crystal. Displacement parameters, unit cells and observed structures all change smoothly with changes in M I ionic radii and M III—N distances.

STRUCTURAL AND ELECTRONIC PROPERTIES OF THE Li/Si(001) SURFACE

1996 ◽  
Vol 03 (03) ◽  
pp. 1487-1494
Author(s):  
J.W. CHUNG
Keyword(s):  
Electronic Properties ◽  
Binding Sites ◽  
Room Temperature ◽  
Structural Models ◽  
Metallic Phase ◽  
Surface Band ◽  
Ordered Structures ◽  
Initial Stage ◽  
Structural And Electronic Properties ◽  
Characteristic Features

Atomic arrangements and electronic properties of the Li-adsorbed Si(001) surface are briefly reviewed. Characteristic features of a series of ordered structures with increasing Li coverage at room temperature are described. Structural models invoking a dimer flipping mechanism are discussed for the first two ordered structures, (2×2)-Li and (2×1)-Li, which are proposed as reconstructions of the silicon substrate. It is shown that the metallic phase found at an initial stage of adsorption is a result of substrate metallization, which explains the presence of an intraband surface plasmon. The features of the surface band structures for the first two ordered structures are discussed in terms of variation of the binding sites with coverage. All the unique features of the Li/Si(001) surface essentially exhibit the size effects of Li.

Green Amide Bond Formation in Water via Direct Coupling of Metal Carboxylate Salts with Ammonium Salts at Room Temperature

2021 ◽  
Author(s):  
Truong Thanh Tung ◽  
John Nielsen
Keyword(s):  
Room Temperature ◽  
Bond Formation ◽  
Direct Coupling ◽  
Ammonium Salts ◽  
Amide Bond ◽  
Metal Carboxylate ◽  
Amide Bond Formation ◽  
Simple Protocol

Herein, we report the green, expedite, and practically simple protocol for direct coupling of carboxylate salts and ammonium salts under ACN/H2O conditions at room temperature without the addition of tertiary...

scholarly journals Ba5(IO6)2: crystal structure evolution from room temperature to 80 K

2021 ◽  
Vol 77 (6) ◽  
pp. 634-637
Author(s):  
David Wenhua Bi ◽  
Priya Ranjan Baral ◽  
Arnaud Magrez
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Structural Transition ◽  
Rietveld Method ◽  
Structural Parameters ◽  
Structure Evolution ◽  
X Ray Diffraction ◽  
Lattice Contraction ◽  
Interatomic Distances ◽  
Crystallographic Axes

The crystal structure of Ba5(IO6)2, pentabarium bis(orthoperiodate), has been re-investigated at room temperature based on single-crystal X-ray diffraction data. In comparison with a previous crystal structure determination by the Rietveld method, an improved precision of the structural parameters was achieved. Additionally, low-temperature measurements allowed the crystal structure evolution to be studied down to 80 K. No evidence of structural transition was found even at the lowest temperature. Upon cooling, the lattice contraction is more pronounced along the b axis. This contraction is found to be inhomogeneous along different crystallographic axes. The interatomic distances between different Ba atoms reduce drastically with lowering temperature, resulting in a closer packing around the IO6 octahedra, which remain largely unaffected.

scholarly journals The Isomorphous Structures of Ammonium trans-Diiodobis(ethanedial-dioximato-(1–)-N,N′)cobaltate(III) and Ammonium trans-Diiodobis(ethanedial-dioximato-(1–)-N,N′)rhodate(III): Extended Metaloximate Chains with a Novel ···I–M–I···I–M–I··· Zigzagged Structure

1990 ◽  
Vol 45 (11) ◽  
pp. 1508-1512 ◽  
Author(s):  
Michel Mégnamisi-Bélombé ◽  
Bernhard Nuber
Keyword(s):  
Room Temperature ◽  
Ammonium Salts ◽  
Monoclinic Space Group ◽  
Hydroxyl Groups ◽  
Coordination Geometry ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Anionic Complexes ◽  
Complex Anions

The ammonium salts of the complex anions trans-diiodobis(ethanedial-dioximato)-cobaltate(III), [Col2(GH)2]-, and trans-diiodobis(ethanedial-dioximato)rhodate(III), [RhI2(GH)2]- (GH- = ethanedial dioximate or glyoximate), have been synthesized and their structures determined from single crystal X-ray diffraction data at room temperature. The crystals of the two salts are monoclinic, space group C2/c. NH4[CoI2(GH)2] (I) crystallizes as dark-brown prisms with a greenish reflectance; its crystal data are: C4H10Col2N5O4, Mr = 504.90; a = 8.910(6), b = 11.700(9), c = 11.691(6) Å; β = 93.55(5)°; V = 1216.4 Å3; Z = 4; Dc = 2.78 Mg m-3. NH4[RhI2(GH)2] (II) crystallizes as yellow-brown blocks with crystal data: C4H10I2N5O4Rh, Mr = 548.88; a = 9.038(4), b = 11.949(5), c = 11.770(3) Å; β = 95.54(3)°; V = 1265.16 A3; Z = 4; Dc = 2.87 Mg m-3. The two structures were refined to a final RW = 0.045 for 1209 observed independent reflections and 95 parameters for I, and to a final RW = 0.040 for 1922 observed independent reflections and 87 parameters for II. The coordination geometry around Co or Rh in the anionic complexes is a distorted (4 + 2) octahedron of four equatorial chelating N atoms and two apical iodides. The H atoms of the hydroxyl groups are involved, as usual, in intramolecular O—H—O bridges with uniform Ο···Ο separations of 2.582 Å for I, and 2.713 Å for II. The rectilinear I—Co—I or I—Rh—I triads form “infinite” zigzag chains extending parallel to the ab plane, with a weak I—I contact of 3.988 Å for I, and 4.010 Å for II.

scholarly journals Molecular-level electrochemical doping for fine discrimination of volatile organic compounds in organic chemiresistors

2020 ◽  
Vol 8 (33) ◽  
pp. 16884-16891 ◽  
Author(s):  
Sooncheol Kwon ◽  
Yusin Pak ◽  
Bongseong Kim ◽  
Byoungwook Park ◽  
Jehan Kim ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Solid State ◽  
Organic Compounds ◽  
Room Temperature ◽  
Molecular Level ◽  
Interfacial Area ◽  
Volatile Organic ◽  
Molecular Scale ◽  
Ppm Level ◽  
State Ionic

A blend of π-CPs and a solid-state ionic liquid provides an enlarged interfacial area at the molecular scale, thereby enabling two-terminal organic chemiresistors (TOCs) with fine discriminatory abilities for sub-ppm-level VOCs at room temperature.

Rh-Catalyzed tandem C–C/C–N bond formation of quinoxalines with alkynes leading to heterocyclic ammonium salts

2019 ◽  
Vol 17 (8) ◽  
pp. 2148-2152 ◽  
Author(s):  
Kangkan Talukdar ◽  
Subhasish Roy ◽  
Raghunath Bag ◽  
Tharmalingam Punniyamurthy
Keyword(s):  
Room Temperature ◽  
Photophysical Properties ◽  
Bond Formation ◽  
Ammonium Salts

Rh-Catalyzed oxidative C–H annulation of 2-arylquinoxalines with alkynes is described to furnish a diverse variety of quinoxalinium salts at room temperature. The substrate scope, isolation of the rhodacycle and photophysical properties are the important features.

Preparation and crystal structure of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7

2008 ◽  
Vol 23 (3) ◽  
pp. 232-240
Author(s):  
Abderrahim Aatiq ◽  
Rachid Bakri ◽  
Aaron Richard Sakulich
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Room Temperature ◽  
Rietveld Method ◽  
Monoclinic Space Group ◽  
Unit Cell Parameters ◽  
Orthorhombic System ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Synthesis and structure of two phosphates belonging to the ternary Sb2O5–In2O3–P2O5 system are realized. Structures of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7 phases, obtained by solid state reaction in air at 950 °C, were determined at room temperature from X-ray powder diffraction using the Rietveld method. SbV1.50InIII0.50(PO4)3 have a monoclinic (space group P21/n) distortion of the Sc2(W O4)3-type framework. Its structure is constituted by corner-shared SbO6 or InO6 octahedra and PO4 tetrahedra. Monoclinic unit cell parameters are a=11.801(2) Å, b=8.623(1) Å, c=8.372(1) Å, and β=90.93(1)°. (Sb0.50In0.50)P2O7 is isotypic with (Sb0.50Fe0.50)P2O7 and crystallizes in orthorhombic system (space group Pna21) with a=7.9389(1) Å, b=16.0664(2) Å, and c=7.9777(1) Å. Its structure is built up from corner-shared SbO6 or InO6 octahedra and P2O7 groups (two group-types). Each P2O7 group shares its six vertices with three SbO6 and three InO6 octahedra, and each octahedron is connected to six P2O7 groups.

scholarly journals Room-Temperature Mg-Ion Conduction Through Molecular Crystal Mg{N(SO2CF3)2}2(CH3OC5H9)2

2021 ◽  
Vol 9 ◽  
Author(s):  
Takaaki Ota ◽  
Shota Uchiyama ◽  
Keiichi Tsukada ◽  
Makoto Moriya
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Ionic Conductivity ◽  
Molecular Crystal ◽  
Solid Electrolytes ◽  
Room Temperature ◽  
Molecular Crystals ◽  
Transference Number ◽  
Ion Conducting ◽  
State Ionic

Molecular crystals have attracted increasing attention as a candidate for innovative solid electrolytes with solid-state Mg-ion conductivity. In this work, we synthesized a novel Mg-ion-conducting molecular crystal, Mg{N(SO2CF3)2}2(CH3OC5H9)2 (Mg(TFSA)2(CPME)2), composed of Mg bis(trifluoromethanesulfonyl)amide (Mg(TFSA)2) and cyclopentyl methyl ether (CPME) and elucidated its crystal structure. We found that the obtained Mg(TFSA)2(CPME)2 exhibits solid-state ionic conductivity at room temperature and a high Mg-ion transference number of 0.74. Contrastingly, most Mg-conductive inorganic solid electrolytes require heating above 150–300°C to exhibit ionic conductivity. These results further prove the suitability of molecular crystals as candidates for Mg-ion-conducting solid electrolytes.

scholarly journals On the crystal structure of the ordered vacancy compound Cu3In5Te9

2019 ◽  
Vol 65 (4 Jul-Aug) ◽  
pp. 360 ◽  
Author(s):  
G. E. Delgado ◽  
C. Rincón ◽  
G. Marroquin
Keyword(s):  
Crystal Structure ◽  
Diffraction Data ◽  
Rietveld Method ◽  
Structural Models ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

The crystal structure of the ordered vacancy compound (OVC) Cu3In5Te9 was analyzed using powder X-ray diffraction data. Several structural models were derived from the structure of the Cu-poor Cu-In-Se compound b-Cu0.39In1.2Se2 by permuting the cations in the available site positions. The refinement of the best model by the Rietveld method in the tetragonal space group P2c (Nº 112), with unit cell parameters a = 6.1852(2) Å, c = 12.3633(9) Å, V = 472.98(4) Å3, led to Rp = 7.1 %, Rwp = 8.5 %, Rexp = 6.4 %, S = 1.3 for 162 independent reflections. This model has the following Wyckoff site atomic distribution: Cu1 in 2e (0,0,0); In1 in 2f (½,½,0), In2 in 2d (0,½,¼); Cu2-In3 in 2b (½,0,¼); in 2a (0,0,¼); Te in 8n (x,y,z).

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