Hydrogen-bonding-induced oligoanthranilamide foldamers. Synthesis, characterization, and complexation for aliphatic ammonium ions

Tetrahedron ◽  
2005 ◽  
Vol 61 (33) ◽  
pp. 7974-7980 ◽  
Author(s):  
Hui-Ping Yi ◽  
Chuang Li ◽  
Jun-Li Hou ◽  
Xi-Kui Jiang ◽  
Zhan-Ting Li
Keyword(s):  
Hydrogen Bonding ◽  
Ammonium Ions

Raman Spectra of Solid (NH4)2CrO4 and (ND4)2CrO4 Obtained by a Rotating Cell Technique

1976 ◽  
Vol 30 (2) ◽  
pp. 187-190 ◽  
Author(s):  
Robert L. Carter ◽  
L. Kevin O'Hare
Keyword(s):  
Hydrogen Bonding ◽  
Alkali Metal ◽  
Raman Spectra ◽  
Sampling Technique ◽  
Solid Sampling ◽  
Monoclinic Structure ◽  
Ammonium Ions ◽  
Cylindrical Cell ◽  
Sample Rotation ◽  
Rotation Technique

The Raman spectra of polycrystalline (NH4)2CrO4 and (ND4)2CrO4 have been obtained by a sample rotation technique where the uncompressed solid is contained in a glass cylindrical cell. The apparatus is a commerically available sample rotator for liquids, which was modified for the described solid sampling technique. The Raman spectra of (NH4)2CrO4 and (ND4)2CrO4 are discussed in relation to their uniquely monoclinic structure, in contrast to the β-K2SO4 structure found for (NH4)2SO4 and many alkali metal chromates and sulfates. The hydrogen bonding in (NH4)2CrO4 is described, and its role in determining both the structure and the Raman spectra is discussed. The data suggest a barrier to NH4+ rotation of approximately 3.70 kcal/mol, indicating that the ammonium ions are not freely rotating on the time scale of the Raman experiment (10−13 sec).

Optimization of a phosphine oxide disulfoxide array for multipoint hydrogen bonding to ammonium ions

1993 ◽  
Vol 115 (17) ◽  
pp. 7900-7901 ◽  
Author(s):  
Paul B. Savage ◽  
Steven K. Holmgren ◽  
Samuel H. Gellman
Keyword(s):  
Hydrogen Bonding ◽  
Phosphine Oxide ◽  
Ammonium Ions

Hydrogen-Bonding-Mediated Dynamic Covalent Synthesis of Macrocycles and Capsules: New Receptors for Aliphatic Ammonium Ions and the Formation of Pseudo[3]rotaxanes

2009 ◽  
Vol 15 (23) ◽  
pp. 5763-5774 ◽  
Author(s):  
Xiao-Na Xu ◽  
Lu Wang ◽  
Gui-Tao Wang ◽  
Jian-Bin Lin ◽  
Guang-Yu Li ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Ammonium Ions

The Preparation and Crystal Structure of the Bismuth(III) Catecholate Complex Adduct (NH4)2[Bi2(C6H4O2)4].(C6H6O2)2.2H2O

1994 ◽  
Vol 47 (7) ◽  
pp. 1413 ◽  
Author(s):  
G Smith ◽  
AN Reddy ◽  
KA Byriel ◽  
CHL Kennard
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Complex Anion ◽  
X Ray Diffraction ◽  
Ammonium Ions ◽  
Centrosymmetric Dimer ◽  
X Ray ◽  
Catecholate Complex

(NH4)2[Bi2(C6H4O2)4].(C6H6O2)2.2H2O, a bismuth(III)-catechol complex adduct, has been prepared and its structure determined by X-ray diffraction methods. The complex anion is a centrosymmetric dimer comprising two five-coordinate [ bis ( catecholato (2-)) bismuthate (III)] centres [Bi-O, 2.177(4), 2.222(4) Ǻ and 2.150(3), 2.322(4)Ǻ], bridged by one of the catechol oxygens [Bi-O, 2.653(3)Ǻ]. In addition, the structure is stabilized by hydrogen bonding involving the ammonium ions, the lattice waters and the two adduct catechol molecules.

The Influence of Pressure on the Infrared-Spectra of Hydrogen-Bonded Solids. VII. Deuterated Ammonium Salts

1988 ◽  
Vol 41 (12) ◽  
pp. 1935 ◽  
Author(s):  
SD Hamann
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Ammonium Salts ◽  
Ammonium Ions ◽  
Hydrogen Bonded

The infrared stretching and bending frequencies of isotopically dilute +NHD3 ions in predominantly +ND4 salts have been measured at pressures up to 5 GPa at 25°C. For most of the 28 salts studied, the stretching bands move to higher frequencies with increasing pressure, these results suggesting the absence of any significant hydrogen bonding between the ammonium ions and the anions in the crystals.

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.

scholarly journals Nitrogen as a Probe Molecule for the IR Studies of the Heterogeneity of OH Groups in Zeolites

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6261
Author(s):  
Łukasz Kuterasiński ◽  
Mariusz Gackowski ◽  
Jerzy Podobiński ◽  
Dorota Rutkowska-Zbik ◽  
Jerzy Datka
Keyword(s):  
Hydrogen Bonding ◽  
Frequency Shift ◽  
The Other ◽  
Probe Molecule ◽  
Ammonium Ions ◽  
Oh Groups ◽  
Desorption Temperature ◽  
Ir Studies ◽  
Ammonia Desorption ◽  
Ir Bands

One of the methods of IR studies of the heterogeneity of Si–OH–Al groups in zeolites is the investigation of the frequency shift of the band of free OH bands restored upon the adsorption of ammonia and subsequent desorption at increasing temperatures. We extended this method by following the shift of the band of the OH group interacting by hydrogen bonding with nitrogen. The advantage of nitrogen, compared with CO, which has been commonly used as a probe molecule in studies on hydrogen bonding, is that for nitrogen the frequency shift is smaller than for CO and therefore there is no overlapping of shifted OH band with the bands of ammonium ions. For zeolites NaHY, HMFI, and HBEA, the frequency shift of IR bands of both free and hydrogen-bonded Si–OH–Al with the increase of ammonia desorption temperature evidences the heterogeneity of these hydroxyls. On the other hand, in zeolite HFAU of Si/Al = 31, Si–OH–Al were found to be homogeneous. Heterogeneity of OH groups may be explained both by the presence of Si–OH–Al of various number of Al near the bridge and of Si–OH–Al of various geometry.

Octaammonium diaquahexa-μ2-oxalato-dioxalatotetracopper(II) tetrahydrate

2006 ◽  
Vol 62 (5) ◽  
pp. m1139-m1141 ◽  
Author(s):  
Karim Kadir ◽  
Trifa Mohammad Ahmed ◽  
Dag Noreús ◽  
Lars Eriksson
Keyword(s):  
Hydrogen Bonding ◽  
Water Molecule ◽  
Title Compound ◽  
Water Molecules ◽  
Ammonium Ions ◽  
Solvent Water ◽  
Oxalate Ligand ◽  
Hydrogen Bonding Network

In the structure of the title compound, (NH4)8[Cu4(C2O4)8(H2O)2]·4H2O, isolated tetramers of [Cu(ox)2]2+ (ox is oxalate) are present. Each CuII ion coordinates to four O atoms in two oxalate ligands and to two more distant O atoms in a neighbouring oxalate ligand or a water molecule. An extensive hydrogen-bonding network connects the tetramers to two unique solvent water molecules and four ammonium ions.

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