Hydrogen-bonded complexes of perfluoro-t-butanol with acetone and nitromethane in low temperature solutions and matrices

1991 ◽  
Vol 69 (10) ◽  
pp. 1520-1527 ◽  
Author(s):  
Louise Schriver ◽  
André Schriver ◽  
Stefan Peil ◽  
Otto Schrems
Keyword(s):  
Hydrogen Bonding ◽  
Low Temperature ◽  
Key Words ◽  
Infrared Spectra ◽  
Temperature Effects ◽  
Bonding Temperature ◽  
Proton Donor ◽  
Frequency Shifts ◽  
Binary Complexes ◽  
Solid Matrices

Infrared spectra are reported for binary complexes between perfluoro-tert-butanol as proton donor and nitromethane and acetone as bases. The complexes have been investigated in low temperature solutions and in cryogenic matrices. The spectra have been evaluated in terms of frequency shifts (ΔVOH), half widths (FWHH) and anharmonicities (κ) caused by the hydrogen bonding of these complexes. The influence of the environment (solvents and solid matrices) as well as temperature on the spectra of the complexes has also been studied and is discussed in detail. Key words: hydrogen bonding, temperature effects, solutions, matrix.

Low-temperature infrared studies of some acid–base reactions

1983 ◽  
Vol 61 (9) ◽  
pp. 2077-2088 ◽  
Author(s):  
Theresa Huston ◽  
I. C. Hisatsune ◽  
Julian Heicklen
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectroscopy ◽  
Low Temperature ◽  
Infrared Spectra ◽  
Acid Base ◽  
Reaction Systems ◽  
Solid States ◽  
Infrared Studies

Low-temperature infrared spectroscopy has been used to examine the systems NH3 + H2O, NH3 + HCl, H2O + HCl, NH3 + HNO3, and NH2OH + HNO3. Hydrogen-bonding in the solid states greatly reduces the reactivities in these systems. Temperatures where reactions initiated in the systems NH3(s) + HCl(g), HNO3(s) + NH3(g), H2O(s) + HCl(g), and NH2OH(s) + HNO3(s) were, respectively, −145, −130, −127, and −125 °C. Infrared spectra of 2NH3•H2O, NH3•H2O, NH4Cl•3NH3, NH4NO3•3NH3, NH4NO3•2HNO3, NH2OH2+NO3−, NH3OH+NO3−, H3O+Cl−, H5O2+Cl−, and H5O2+Cl−•H2O have been identified in these reaction systems.

A Low Temperature Infrared Study of Self-association in Thiols

1972 ◽  
Vol 50 (22) ◽  
pp. 3594-3600 ◽  
Author(s):  
R. Bicca de Alencastro ◽  
C. Sandorfy
Keyword(s):  
Hydrogen Bonding ◽  
Low Temperature ◽  
Infrared Spectra ◽  
Low Temperatures ◽  
Infrared Study ◽  
Text Type ◽  
Stretching Vibration ◽  
Aliphatic Thiols ◽  
Self Association ◽  
Associated Species

The infrared spectra of several aliphatic thiols and of benzenethiol were measured between 2400 and 2700 cm−1, and 4800 and 5300 cm−1 in a 1:1 mixture of CCl3F and C2F4Br2, at temperatures ranging from 20 to −190 °C. Dimerization takes place at low temperatures and more highly associated species also appear. Free S—H groups are present in the solutions as well as in the pure liquids, even at the lowest temperatures. The association is of the [Formula: see text] type in aliphatic thiols; both [Formula: see text] and [Formula: see text] bonds are found in the case of benzenethiol and α-toluenethiol. Hydrogen bonding has little effect on the anharmonicity of the S—H stretching vibration.

Infrared spectra of the ammonium ion in crystals. Part XIV. Hydrogen bonding and orientation of the ammonium ion in fluorides, with observations on the transition temperatures in cubic cryolite, elpasolite, and perovskite halides

1985 ◽  
Vol 63 (12) ◽  
pp. 3328-3353 ◽  
Author(s):  
Osvald Knop ◽  
Wolfgang J. Westerhaus ◽  
Michael Falk ◽  
Werner Massa
Keyword(s):  
Hydrogen Bonding ◽  
Low Temperature ◽  
Infrared Spectra ◽  
Room Temperature ◽  
Halogen Atom ◽  
Ammonium Ion ◽  
Transition Temperatures ◽  
Coordination Numbers ◽  
Geometric Tolerance ◽  
Ionic Size

The ir spectra of the isotopic probe ion NH3D+ have been used to obtain information about the symmetry, orientation, and hydrogen-bonding involvement of the ammonium ion, between 10 K and room temperature, in NH4F, NH4HF2, (NH4)2[Cr(H2O)6]F5, NH4PF6, (NH4)3SiF7, the elpasolites (NH4)2BFeF6 (B = Na, K) and CS2NH4MF6 (M = Fe, Al), and the cryolites (NH4)3MF6 (M = Al, Cr, Fe). Several of these fluorides exhibit low-temperature transitions, some of which are evident in the probe-ion spectra. It is shown that relating the isotopically isolated ND stretching and bending frequencies to the [Formula: see text] distances and to the coordination numbers of the ammonium ion reveals important trends in the dependence of the behaviour of the ion on its immediate environment in the crystal. A detailed discussion is presented of the effect of ionic size and the geometric tolerance factor t on the transition temperatures of cubic cryolite, perovskite, and elpasolite halides, as well as on the anisotropy of the principal thermal amplitudes of the halogen atom in such compounds. The relation between Ttr and the frequency of the ND stretching absorption of NH3D+ in the ammonium representatives of these classes of halides is also explored.

A SPECTROSCOPIC STUDY OF HYDROGEN BONDING IN PERFORMIC AND PERACETIC ACIDS

1952 ◽  
Vol 30 (11) ◽  
pp. 821-830 ◽  
Author(s):  
Paul A. Giguère ◽  
A. Weingartshofer Olmos
Keyword(s):  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Spectroscopic Study ◽  
Infrared Spectra ◽  
Peracetic Acid ◽  
The Other ◽  
Frequency Shifts ◽  
Vapor State ◽  
Nonpolar Solvents ◽  
Intramolecular Hydrogen

The infrared spectra of concentrated performic and peracetic acids were measured in the rock-salt region. The most significant features are theO—H stretching frequency at 3310–3350 cm−1 and the OH bending frequency at 1450 cm−1 which, for both peracids, remain essentially the same in the vapor state as in the liquid or in solution in nonpolar solvents. This is attributed to intramolecular hydrogen bonds resulting in particularly stable five-membered rings,[Formula: see text]Steric conditions in the percarboxylic group are favourable to such ring formation or chelation. From the observed frequency shifts the energy of these hydrogen bonds is estimated to be about 7 kcal. per mole. No evidence for unchelated molecules was found even in very dilute solutions of peracetic acid in nonpolar solvent nor in the vapour at low pressure and moderate temperature. Tentative assignments of the other frequencies in the spectra of the peracids are made by comparison with those of formic and acetic acids.The danger involved in handling these peracids in concentrated form is emphasized.

scholarly journals Low-temperature infrared spectra and hydrogen bonding in polycrystalline dl-serine and deuterated derivatives

2006 ◽  
Vol 41 (1) ◽  
pp. 73-82 ◽  
Author(s):  
S. Jarmelo ◽  
I. Reva ◽  
M. Rozenberg ◽  
P.R. Carey ◽  
R. Fausto
Keyword(s):  
Hydrogen Bonding ◽  
Low Temperature ◽  
Infrared Spectra

Solvent effects on the infrared spectra of anilines. IV. Secondary aromatic amines and amides with trifluoromethyl or phenyl as ortho substituents

1967 ◽  
Vol 20 (1) ◽  
pp. 93 ◽  
Author(s):  
LK Dyall
Keyword(s):  
Hydrogen Bonding ◽  
Infrared Spectra ◽  
Aromatic Amines ◽  
Secondary Amines ◽  
Substituted Anilines ◽  
Frequency Shifts ◽  
Solvent Shift ◽  
Bonding Properties ◽  
Solvent Shifts ◽  
Ortho Substituent

The N-H stretching frequencies of five N-substituted anilines with trifluoro- methyl or phenyl as ortho substituent have been measured in a variety of solvents. Elevation of v(NH) by steric compression is observed. The frequency shifts observed for N-methyl-2-phenylaniline fit none of the three classes of solvent shift behaviour recognized for other ortho-substituted secondary amines. The results confirm that solvent shifts of v(NH) cannot be used to distinguish between the steric and hydrogen bonding properties of the ortho substituent.

Sign in / Sign up

Export Citation Format

Share Document