Infrared Spectra of the Ammonium Ion in Crystals. II. The Ammonium Ion in Trigonal Environments, with a Consideration of Hydrogen Bonding

1975 ◽  
Vol 53 (22) ◽  
pp. 3394-3400 ◽  
Author(s):  
Ian A. Oxton ◽  
Osvald Knop ◽  
Michael Falk
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Isotopic Dilution ◽  
Ammonium Ion ◽  
Ammonium Ions ◽  
Dilution Technique ◽  
Intensity Ratios ◽  
Normal Hydrogen ◽  
Trifurcated Hydrogen Bond

Infrared spectra of polycrystalline (NH4)2GeF6, β-(NH4)2SiF6, and (NH4)2Pb(SO4)2 have been recorded at room and liquid-nitrogen temperatures. The N—D stretching and bending fundamentals of the isotopically dilute NH3D+ ion in these compounds have been studied with particular attention. The occurrence of N—D stretching doublets and bending triplets, of approximate intensity ratios 1:3 and 2:3:3 respectively, confirms the C3v symmetry of the ammonium ion and suggests that the isotopic dilution technique will prove useful as a diagnostic tool for ascertaining site symmetries of the ammonium ion. The spectra are consistent with non-rotating ammonium ions. The frequencies of dilute NH3D+ ions suggest that for the ammonium ion in (NH4)2Pb(SO4)2 a trifurcated hydrogen bond is stronger than a normal hydrogen bond.

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.

THE STUDY OF HYDROGEN BONDING AND RELATED PHENOMENA BY SPECTROSCOPIC METHODS: PART VIII. THE ULTRAVIOLET AND INFRARED SPECTRA OF SOME 2,4-DINITRODIPHENYLAMINES

1964 ◽  
Vol 42 (12) ◽  
pp. 2674-2683 ◽  
Author(s):  
A. Balasubramanian ◽  
J. B. Capindale ◽  
W. F. Forbes
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Spectral Data ◽  
Intramolecular Hydrogen Bond ◽  
Infrared Spectra ◽  
Positive Charge ◽  
Spectroscopic Methods ◽  
Amino Group ◽  
Strong Type ◽  
Intramolecular Hydrogen

The ultraviolet spectra of a number of 2,4-dinitrodiphenylamines suggest that these compounds are generally non-planar in a number of different solvents. The infrared and ultraviolet spectral data in different solvents also suggest that an intramolecular hydrogen bond is present in these molecules, at least in inert solvents. There is evidence that a p-nitro substituent is necessary to increase the positive charge on the amino group sufficiently to permit it to form this fairly strong type of hydrogen bond.

The effects of selected gases upon ethanol: hydrogen bond breaking by O2 and N2

1985 ◽  
Vol 63 (7) ◽  
pp. 1864-1869
Author(s):  
T. L. Mathers ◽  
G. Schoeffler ◽  
S. P. McGlynn
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Aromatic Hydrocarbons ◽  
Bonding Process ◽  
Bond Breaking ◽  
Temperature Dependency ◽  
Normal Hydrogen ◽  
Luminescence Characteristics

The temperature dependency of the phosphorescence properties of aromatic hydrocarbons in alcoholic glasses exhibits a number of phenomena that have not been described previously. Chief among these are the effects of added gases (O2, N2, C2H6, Ar), some of which produce major changes in the luminescence characteristics. These are discussed, and rationalized in terms of a model which presumes that O2 and N2 can disrupt the normal hydrogen bonding process between alcohol molecules.

Infrared spectra of the ammonium ion in crystals. Part VI. Hydrogen bonding in simple and complex ammonium halides

1979 ◽  
Vol 57 (15) ◽  
pp. 2003-2003
Author(s):  
Osvald Knop ◽  
Ian A. Oxton ◽  
Michael Falk
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Ammonium Ion ◽  
Ammonium Halides

not available

Vibrational spectroscopy of semiheavy water (HDO) as a probe of solute hydration

2010 ◽  
Vol 82 (10) ◽  
pp. 1869-1887 ◽  
Author(s):  
Maciej Śmiechowski ◽  
Janusz Stangret
Keyword(s):  
Spectral Analysis ◽  
Vibrational Spectroscopy ◽  
Infrared Spectra ◽  
Isotopic Dilution ◽  
Vibrational Modes ◽  
Analysis Method ◽  
Dilution Technique ◽  
Difference Spectra ◽  
Quantitative Version ◽  
The Difference

Vibrational spectroscopy is an ideally suited tool for the study of solute hydration. Nevertheless, water is commonly considered by spectroscopists a difficult solvent to work with. However, by using the isotopic dilution technique, in which a small amount of D2O is introduced into H2O or vice versa with formation of semiheavy water (HDO), many technical and interpretative problems connected with measurement of infrared spectra of water may be circumvented. Particularly, the isotopic decoupling of stretching vibrational modes greatly simplifies interpretation of the spectra. Systematic studies conducted in several laboratories since the 1980s up to the present day have provided a vast amount of data, concerning mainly ionic hydration. Many of these experiments have been performed in our laboratory. The analysis method we applied is based on the quantitative version of the difference spectra technique and allows separation of the spectrum of solute-affected HDO from the bulk solvent. This review illustrates the development of vibrational spectroscopy of HDO and spectral analysis methods over the years, as well as summarizes the results obtained for ionic and nonionic solutes, including some general hydration models formulated on their basis.

The correlation between O—H stretching frequencies and hydrogen bond distances in a crystalline sugar monohydrate

1979 ◽  
Vol 57 (19) ◽  
pp. 2640-2645 ◽  
Author(s):  
J. Umemura ◽  
G. I. Birnbaum ◽  
D. R. Bundle ◽  
W. F. Murphy ◽  
H. J. Bernstein ◽  
...  
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Isotopic Dilution ◽  
X Ray

The Raman and infrared spectra of crystalline methyl 3,6-dideoxy-β-D-ribo-hexopyranoside monohydrate in the O—H stretching region have been studied at room temperature and lower temperatures. Four bands have been identified and correlated with the corresponding O … O distances of the four distinct hydrogen bonds obtained from X-ray data. The assignments were substantiated by a deuterium isotopic dilution study.

THE STUDY OF HYDROGEN BONDING AND RELATED PHENOMENA BY SPECTROSCOPIC METHODS: PART VII. INTRAMOLECULAR HYDROGEN BONDING AND STERIC INTERACTIONS IN o-NITROBENZALDEHYDE AND RELATED COMPOUNDS

1962 ◽  
Vol 40 (10) ◽  
pp. 1891-1898 ◽  
Author(s):  
W. F. Forbes
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Intramolecular Hydrogen Bonding ◽  
Spectroscopic Methods ◽  
Steric Interactions ◽  
Spectral Changes ◽  
Suitable Reference ◽  
Intramolecular Hydrogen ◽  
Related Compounds

Certain unusual features in the infrared spectra of o-nitrobenzaldehyde have been interpreted either in terms of an intramolecular hydrogen bond or in terms of steric interactions. As an extension of these studies we have investigated the ultraviolet, infrared, and n.m.r. spectra of o-nitrobenzaldehyde and of suitable reference compounds and have re-examined the available other evidence. It is concluded that the observed spectral changes can best be explained in terms of steric interactions rather than in terms of intramolecular hydrogen bonding.

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.

Structures ofN-acetyl-DL-isoleucine,N-acetyl-DL-alloisoleucine and their ammonium salts; role of ammonium ions in crystal structure formation

2016 ◽  
Vol 72 (4) ◽  
pp. 650-657
Author(s):  
Tatsuo Yajima ◽  
Makiko Kimura ◽  
Yoshihiro Hori ◽  
Tadashi Shiraiwa
Keyword(s):  
Hydrogen Bond ◽  
Room Temperature ◽  
Optically Active ◽  
Ammonium Salts ◽  
Ammonium Ion ◽  
Amino Group ◽  
Ammonium Ions ◽  
Screw Axis ◽  
Crystal Structure Formation

The crystal structures ofN-acetyl-DL-isoleucine,N-acetyl-DL-alloisoleucine and their ammonium salts show that these four compounds exist as racemic compounds around room temperature. The two ammonium salts are arranged around a 21screw axis, forming a helical column which consists of ammonium ions and single enantiomeric anions similar to the crystals of the ammonium salts of optically activeN-acetyl-L-isoleucine andN-acetyl-D-alloisoleucine. The ammonium ion and the carboxylate ion in the helix are connected by three hydrogen bonds, the fourth hydrogen bond being formed between the ammonium ion and an external acetyl amino group of the neighboring helical column. The fourth hydrogen bond is formed between the ammonium ion and an external acetyl amino group of the neighboring 21column. AmmoniumN-acetyl-DL-alloisoleucinate was revealed to exist as an unstable racemic compound due to conformational similarity between the racemic and optically active compounds in the solid state and was optically resolved by fractional crystallization at 293 K.

Sign in / Sign up

Export Citation Format

Share Document