Infrared spectra of the ammonium ion in crystals. Part IX. Ammonium tetraphenylborate, NH4B(C6H5)4: crystal structure at room temperature and at 120 K, and evidence of hydrogen bonding

1980 ◽  
Vol 58 (13) ◽  
pp. 1355-1364 ◽  
Author(s):  
Wolfgang J. Westerhaus ◽  
Osvald Knop ◽  
Michael Falk
Keyword(s):  
Crystal Structure ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Ammonium Ion ◽  
Ammonium Ions ◽  
Coulombic Interaction ◽  
Phenyl Rings ◽  
Librational Motion ◽  
A Site

A determination of the crystal structure of ammonium tetraphenylborate (ATPB) at 120 K shows that the ammonium ion in this crystal, at a site of symmetry D2d, is oriented in a way consistent with the expectation from a simple model based on Coulombic interaction. Infrared spectra of the isotopic ammonium ions obtained between 10 K and room temperature indicate that the effect of the tetraphenylborate anion on the strength of the N—H bond (as measured by the stretching frequency) is small and independent of temperature, and that the distortion of the ammonium ion from Td symmetry is slight. From the combined evidence it is concluded that the ammonium ion in ATPB must be regarded as hydrogen-bonded, but the potential field due to the four phenyl rings surrounding the ammonium ion offers little resistance to the bending (and probably also to the librational) motion of the ion.

Infrared spectra of the ammonium ion in crystals. Part XII. Low-temperature transitions in ammonium dichromate, (NH4)2Cr2O7

1982 ◽  
Vol 60 (15) ◽  
pp. 1972-1977
Author(s):  
Gábor Keresztury ◽  
Osvald Knop ◽  
Michael Falk
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Abundance Ratio ◽  
Ammonium Ion ◽  
Ammonium Ions ◽  
Hydrogen Bonding Interactions ◽  
Wide Range ◽  
Ammonium Dichromate ◽  
The Difference

Examination of the infrared spectra of the probe ions NH3D+ and NHD3+ in ammonium dichromate confirms the existence of the lowest (Ttr ~ 125 K) of the three transitions that are known, from nonspectroscopic evidence, to occur in this crystal below room temperature. Below Ttr the ammonium ions are of two types, in an abundance ratio of 1:1 and both of symmetry C1. Above Ttr the probe ion spectra are difficult to interpret in detail. The strength of the hydrogen-bonding interactions covers a wide range, as indicated by the difference between the highest and the lowest values of the isotopically isolated ND stretching frequencies at 10 K, 2392 and 2234 cm−1.

An accurate determination of the structure of ammonium oxamate

1963 ◽  
Vol 275 (1363) ◽  
pp. 469-491 ◽  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Atom ◽  
Accurate Determination ◽  
Three Dimensional ◽  
Ammonium Ion ◽  
Intensity Data ◽  
Single Bond ◽  
Hydrogen Atoms ◽  
Librational Motion

The crystal structure of ammonium oxamate (CONH 2 .COONH 4 ) has been studied using Cu Ka X-radiation, by means of a three-circle diffractometer incorporating a xenon-filled proportional counter. Accurate three-dimensional intensity data were collected and a least-squares refinement was carried out. The positions of the hydrogen atoms were obtained and refined. A peak of electron density, about half as high as a hydrogen atom, was observed at the centre of the C—C bond and a correction applied for it increased the length of the bond by 0.003 Å. The bond lengths were corrected for librational motion, and the values obtained are C—C =1.564 ±0.002 Å; C—N = 1.324± 0.002 Å; C—O (amidic) = 1.248± 0.002 A; C— O (carboxylate) = 1.257 + 0.003 Å and 1.256 ± 0.003 Å. The oxamate ion is found to be planar, and the ammonium ion tetrahedral. The length of the C—C bond is greater than any theoretical value yet suggested for the length of a single bond between trigonally hybridized carbons atoms.

Single Crystal Growth of High-Pressure Phases of Ice and Salt Hydrate Far Below the Original Melting Point by Mixing Alcohol: Crystal Structure Determination of Magnesium Chloride Heptahydrate

2020 ◽  
Author(s):  
Keishiro Yamashita ◽  
Kazuki Komatsu ◽  
Hiroyuki Kagi
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
Crystal Growth ◽  
Single Crystal ◽  
Room Temperature ◽  
Growth Technique ◽  
Salt Hydrate ◽  
X Ray

An crystal-growth technique for single crystal x-ray structure analysis of high-pressure forms of hydrogen-bonded crystals is proposed. We used alcohol mixture (methanol: ethanol = 4:1 in volumetric ratio), which is a widely used pressure transmitting medium, inhibiting the nucleation and growth of unwanted crystals. In this paper, two kinds of single crystals which have not been obtained using a conventional experimental technique were obtained using this technique: ice VI at 1.99 GPa and MgCl<sub>2</sub>·7H<sub>2</sub>O at 2.50 GPa at room temperature. Here we first report the crystal structure of MgCl2·7H2O. This technique simultaneously meets the requirement of hydrostaticity for high-pressure experiments and has feasibility for further in-situ measurements.

Infrared spectra of the ammonium ion in crystals. Part VIII. Spectroscopic criteria of highly-bent hydrogen bonds

1980 ◽  
Vol 58 (9) ◽  
pp. 867-874 ◽  
Author(s):  
Osvald Knop ◽  
Wolfgang J. Westerhaus ◽  
Michael Falk
Keyword(s):  
Low Temperature ◽  
Hydrogen Bonds ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Ammonium Ion ◽  
Temperature Transition ◽  
Increasing Temperature

Available evidence suggests that (1) the stretching frequencies of highly-bent hydrogen bonds decrease with increasing temperature, regardless of whether the bonds are static or dynamic in character, to a single acceptor or to several competing acceptors; and (2) departures from symmetric trifurcation (or bifurcation) toward asymmetric situations lower the stretching frequency. In further support of these criteria isotopic probe ion spectra between 10 K and room temperature have been obtained for taurine and for trigonal (NH4)2MF6 (M = Si, Ge, Sn, Ti). Evidence of a low-temperature transition at 100(10) K in trigonal (NH4)2SnF6 is presented, and existence of the previously reported transition at 38.6 K in trigonal (NH4)2SiF6 is confirmed. Symmetry changes associated with these transitions are discussed.

Versuche zur Synthese 2.2′-disubstituierter cis-Bis(phenyl)bis(triphenylphosphan)platin(II)-Verbindungen und Kristallstruktur des cis-Bis(2-nitrophenyl)bis(triphenylphosphan)platin(II) / On the Formation of 2,2′-Disubstituted cis-Bis-(phenyl)bis(triphenylphosphane)platinum(II) Compounds and Crystal Structure Determination of cis-Bis(2-nitrophenyl)bis(triphenylphosphane)platinum(II)

1984 ◽  
Vol 39 (3) ◽  
pp. 359-368 ◽  
Author(s):  
Hans-Albert Brune ◽  
Manfred Wiege ◽  
Tony Debaerdemaeker
Keyword(s):  
Crystal Structure ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
Reaction Paths ◽  
X Ray ◽  
Phenyl Rings

Syntheses of 2,2′-disubstituted cis-Bis(phenyl)bis(ligand)platinum(II) compounds are described with respect to the influence of the ortho-substituents on reaction paths. Configuratior and conformation of the substituted phenyl rings are established by an X-ray structure determination of cis-Bis(2-nitrophenyl)bis(triphenylphosphane)platinum(II).

scholarly journals Solid-State Synthesis, Characterization, and Biological Activity of the Bioinorganic Complex of Aspartic Acid and Arsenic Triiodide

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Guo-Qing Zhong ◽  
Wen-Wei Zhong ◽  
Rong-Rong Jia ◽  
Yu-Qing Jia
Keyword(s):  
Crystal Structure ◽  
Biological Activity ◽  
Solid State ◽  
Complex Formation ◽  
Aspartic Acid ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Biological Test ◽  
Bridge Structure ◽  
Monoclinic System

The bioinorganic complex of aspartic acid and arsenic triiodide was synthesized by a solid-state reaction at room temperature. The formula of the complex is AsI3[HOOCCH2CH(NH2)COOH]2.5. The crystal structure of the complex belongs to monoclinic system with lattice parameters:a=1.0019 nm,b=1.5118 nm,c=2.1971 nm, andβ=100.28°. The infrared spectra can demonstrate the complex formation between the arsenic ion and aspartic acid, and the complex may be a dimer with bridge structure. The result of primary biological test indicates that the complex possesses better biological activity for the HL-60 cells of the leukemia than arsenic triiodide.

scholarly journals Ion-Exchange Reaction Of A-Site In A2Ta2O6 Pyrochlore Crystal Structure

2015 ◽  
Vol 60 (2) ◽  
pp. 941-944 ◽  
Author(s):  
M. Matsunami ◽  
T. Hashizume ◽  
A. Saiki
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Ion Exchange ◽  
Room Temperature ◽  
Electrode Materials ◽  
Pyrochlore Structure ◽  
Rechargeable Battery ◽  
Ion Exchange Reaction ◽  
Li Ion ◽  
A Site

Abstract Na+ or K+ ion rechargeable battery is started to garner attention recently in Place of Li+ ion cell. It is important that A+ site ion can move in and out the positive-electrode materials. When K2Ta2O6 powder had a pyrochlore structure was only dipped into NaOH aqueous solution at room temperature, Na2Ta2O6 was obtained. K2Ta2O6 was fabricated from a tantalum sheet by a hydrothermal synthesize with KOH aqueous solution. When Na2Ta2O6 was dipped into KOH aqueous solution, K2Ta2O6 was obtained again. If KTaO3 had a perovskite structure was dipped, Ion-exchange was not observed by XRD. Because a lattice constant of pyrochlore structure of K-Ta-O system is bigger than perovskite, K+ or Na+ ion could shinny through and exchange between Ta5+ and O2− ion site in a pyrochlore structure. K+ or Na+ ion exchange of A2Ta2O6 pyrochlore had reversibility. Therefore, A2Ta2O6 had a pyrochlore structure can be expected such as Na+ ion rechargeable battery element.

Structure determination of Mg3(OH)5Cl·4H2O (F5 phase) from laboratory powder diffraction data and its impact on the analysis of problematic magnesia floors

2007 ◽  
Vol 63 (6) ◽  
pp. 805-811 ◽  
Author(s):  
Kunihisa Sugimoto ◽  
Robert E. Dinnebier ◽  
Thomas Schlecht
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Room Temperature ◽  
Real Life ◽  
Quantitative Phase Analysis ◽  
Binder Phase ◽  
Powder Diffraction Data ◽  
First Time

The crystal structure with the idealized formula Mg3(OH)5Cl·4H2O, the so-called F5 phase according to 5Mg(OH)2·MgCl2·8H2O in the system MgCl2–MgO–H2O, has been solved ab initio from high-quality laboratory powder diffraction data at room temperature. The F5 phase is structurally related to 3Mg(OH)2·MgCl2·8H2O (F3 form). The F5 phase consists of infinite triple chains with one Mg(OH)6 and two Mg(OH)4(OH2)2 octahedra as building units intercalated by chlorides, which are partly substituted by disordered hydroxides in the real structure. The F5 phase is of technological importance as the most important binder phase in Sorel cements. Knowledge of the crystal structure enables the full quantitative phase analysis of magnesia cements for the first time, which turns out to be very helpful in the search for possible causes of broken or bleached magnesia floors. Two real-life examples are given.

Ammoniovoltaite, (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18, a new mineral from the Severo-Kambalny geothermal field, Kamchatka, Russia

2018 ◽  
Vol 82 (5) ◽  
pp. 1057-1077 ◽  
Author(s):  
Elena S. Zhitova ◽  
Oleg I. Siidra ◽  
Dmitry I. Belakovsky ◽  
Vladimir V. Shilovskikh ◽  
Anton A. Nuzhdaev ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Structure Refinement ◽  
Geothermal Field ◽  
Water Soluble ◽  
Ammonium Ion ◽  
New Mineral ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mössbauer Data

AbstractAmmoniovoltaite, (NH4)2Fe2+5Fe3+3Al(SO4)12(H2O)18, is a new voltaite-group mineral. The mineral was discovered at the Severo-Kambalny (North-Kambalny) geothermal field, Kambalny volcanic ridge, Southern Kamchatka, Russia. Ammoniovoltaite forms at ~100°C around geothermal gas/steam vents in association with alunogen, tschermigite and pyrite. Crystals of ammoniovoltaite have euhedral habit, are up to 50 µm in size and grow on alunogen plates. Ammoniovoltaite is black with vitreous lustre, opaque, brittle and water-soluble. Neither cleavage nor parting is found, the fracture is conchoidal. The mineral is isotropic, with the refractive index n = 1.602(2) (589 nm). Infrared spectra contain an absorption band at 1433 cm–1 distinctive for the ammonium ion. The chemical composition is (iron content is given in accordance with Mössbauer data, H2O calculated from a crystal-structure refinement, wt.%): FeO 13.26, Fe2O3 11.58, MgO 2.33, ZnO 0.04, Al2O3 2.74, SO3 47.46, K2O 0.19, CaO 0.11, (NH4)2O 2.96, H2O 16.03, total 96.70. The empirical formula based on S = 12 atoms per formula unit is [(NH4)1.88K0.08Ca0.04]Σ2.00(Fe2+3.74Mg1.17Fe3+0.05Zn0.01)Σ4.97(Fe3+2.89Al0.09)Σ2.98Al1.00(SO4)12.00(H2O)18.00. The crystal structure has been refined to R1 = 0.031 and 0.030 on the basis of 1217 and 1462 unique reflections with I >2σ(I) collected at 100 K and room temperature, respectively. Ammoniovoltaite is the ammonium analogue of voltaite. The mineral is cubic, Fd$\bar{3}$c, a = 27.250(1) Å and V = 20234(3) Å3 (at 100 K); and a = 27.322(1) Å and V = 20396(3) Å3 (at RT), with Z = 16. The strongest lines of the powder X-ray diffraction pattern [d, Å (I, %) (hkl)] are: 9.67 (74) (022), 7.90 (56) (222), 5.58 (84) (422), 3.560 (100) (731), 3.418 (100) (008) and 2.8660 (37) (931). A brief review of ammonium minerals from various volcanically active geological environments is given.

Infrared spectra of the ammonium ion in crystals. Part XIII. Crystal structure of (NH4)2[AlF5(H2O)] and NH3D+ probe-ion spectra in (NH4)2[AlF5(H2O)], NH4AlF4, and (NH4)3ZnCl5, with remarks on structural filiation of AMF4 fluorides

1985 ◽  
Vol 63 (2) ◽  
pp. 516-525 ◽  
Author(s):  
Osvald Knop ◽  
T. Stanley Cameron ◽  
S. P. Deraniyagala ◽  
D. Adhikesavalu ◽  
Michael Falk
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Infrared Spectra ◽  
The Other ◽  
Ammonium Ion ◽  
Colour Space ◽  
Low Frequencies ◽  
Space Groups ◽  
Disordered Phase ◽  
Normal Formula

The crystal structure of (NH4)2AlF5•H2O = (NH4)2[AlF5(H2O)] (Pbcn, a = 10.192(4) Å, b = 8.037(2) Å, c = 7.844(1) Å, Z = 4) consists of isolated [AlF5(H2O)]2− octahedral and NH4+ ions. The octahedra are linked by [Formula: see text] bonds to form zigzag chains parallel to c and the chains are cross-linked by normal [Formula: see text] hydrogen bonds to the NH4+ ions. The ir characteristics of the hydrogen bonds in this and the other two title compounds were probed with the NH3D+ ion between 10 and 293 K. The probe-ion spectra confirm the C1 symmetry of the ammonium ion in (NH4)2[AlF5(H2O)] and point to [Formula: see text] bonding of moderate strength. For NH4AlF4 the spectra agree with the expectation from the known crystal structure of both the ordered and the disordered phase, but the transition at ~150 K is not evident in the evolution of the spectra with temperature. Detailed assignment of the ND stretching and bending component absorptions of NH3D+ is not possible for (NH4)3ZnCl5 = (NH4)3(ZnCl4)Cl. However, the unusually low frequencies of two of the components of the ND stretching absorptions in this crystal indicate the existence of [Formula: see text] bonds stronger than those in NH4Cl. The filiation of the known AMF4 structures deriving from TlAlF4 is presented in terms of two-colour space groups.

Sign in / Sign up

Export Citation Format

Share Document