Results 291 to 300 of about 289,623 (333)
Some of the next articles are maybe not open access.
Inference: International Review of Science, 2015
The claim that chemistry has been explained in terms of quantum theory is received wisdom. Yet quantum physics is unable to explain the strong association of water molecules in liquid or ice. Marc Henry suggests the hydrogen bond is an emergent property of matter resulting from a non-linear coupling between quantified energy levels of water molecules ...
openaire +2 more sources
The claim that chemistry has been explained in terms of quantum theory is received wisdom. Yet quantum physics is unable to explain the strong association of water molecules in liquid or ice. Marc Henry suggests the hydrogen bond is an emergent property of matter resulting from a non-linear coupling between quantified energy levels of water molecules ...
openaire +2 more sources
Hydrogen bonding in sulfonamides
Journal of Pharmaceutical Sciences, 2001The hydrogen-bond connectivity in 39 sulfonamide crystal structures has been deciphered and described using graph set notation. The hydrogen-bond connectivity observed is used to gain information on hydrogen-bond preferences of specific donor and acceptor atoms of related sulfonamide molecules.
Daniel A. Adsmond, David J.W. Grant
openaire +3 more sources
The Journal of Physical Chemistry A, 2006
In this Article we extend the idea of detecting a hydrogen bond solely on one single quantum chemically determined descriptor. We present an improvement of the method introduced by Reiher et al. (Theor. Chim. Acta 2001, 106, 379), who mapped the strength of the hydrogen bond onto an easily accessible quantity, namely, the two-center shared-electron ...
Barbara Kirchner, Jens Thar
openaire +3 more sources
In this Article we extend the idea of detecting a hydrogen bond solely on one single quantum chemically determined descriptor. We present an improvement of the method introduced by Reiher et al. (Theor. Chim. Acta 2001, 106, 379), who mapped the strength of the hydrogen bond onto an easily accessible quantity, namely, the two-center shared-electron ...
Barbara Kirchner, Jens Thar
openaire +3 more sources
Hydrogen-Bonded Dihydrotetraazapentacenes
Organic Letters, 2012Three new members of N-heteropentacenes explored herein have adjacent pyrazine and dihydropyrazine rings at one end of the pentacene backbone. Interesting findings from this study include self-complementary N-H···N H-bonds in the solid state, solvent-dependent UV-vis absorption caused by H-bonding, and new p-type organic semiconductors with field ...
Qian Miao+4 more
openaire +3 more sources
Reports on Progress in Physics, 1952
A survey is given of the infra-red spectra of substances possessing hydroxyl groups and of the position of the O-H valence vibration in the solid, liquid and gaseous state and in dilute solutions. The spectra of water, alcohols and carboxylic acids are discussed separately; and evidence for molecular association is adduced from the experiments on ...
openaire +2 more sources
A survey is given of the infra-red spectra of substances possessing hydroxyl groups and of the position of the O-H valence vibration in the solid, liquid and gaseous state and in dilute solutions. The spectra of water, alcohols and carboxylic acids are discussed separately; and evidence for molecular association is adduced from the experiments on ...
openaire +2 more sources
Persistent Hydrogen‐Bonded and Non‐Hydrogen‐Bonded Phenoxyl Radicals
Chemistry – A European Journal, 2011AbstractThe production of stable phenoxyl radicals is undoubtedly a synthetic chemical challenge. Yet it is a useful way to gain information on the properties of the biological tyrosyl radicals. Recently, several persistent phenoxyl radicals have been reported, but only limited synthetic variations could be achieved.
Maxim L. Kuznetsov+5 more
openaire +3 more sources
ChemInform, 2007
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
openaire +4 more sources
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
openaire +4 more sources
Journal of Physical Organic Chemistry, 1996
Measurements were made in CCl4 of the formation constant KHB of the 1:1 hydrogen-bonded complexes between the reference donor 4-fluorophenol and the intramolecular hydrogen-bonded systems I (one lone pair on heteroatom Y, one intramolecular hydrogen bond: 8-hydroxyquinaldine and 2-(2-hydroxyphenyl)benzoxazole); II: (two lone pairs, two intramolecular ...
Christian Laurence+3 more
openaire +2 more sources
Measurements were made in CCl4 of the formation constant KHB of the 1:1 hydrogen-bonded complexes between the reference donor 4-fluorophenol and the intramolecular hydrogen-bonded systems I (one lone pair on heteroatom Y, one intramolecular hydrogen bond: 8-hydroxyquinaldine and 2-(2-hydroxyphenyl)benzoxazole); II: (two lone pairs, two intramolecular ...
Christian Laurence+3 more
openaire +2 more sources
Crystallography Reviews, 1995
This article focusses on the crystallographic research aimed at a better understanding of hydrogen bonds which has been published since January 1990. In the interest of continuity, earlier work is quoted when it relates to that published during this period.
openaire +2 more sources
This article focusses on the crystallographic research aimed at a better understanding of hydrogen bonds which has been published since January 1990. In the interest of continuity, earlier work is quoted when it relates to that published during this period.
openaire +2 more sources
Bonding of Hydrogen in Hydrogen Montmorillonite
Nature, 1964RESEARCH concerning bonding conditions for tritium and deuterium in micaceous minerals, as formerly mentioned by us1, indicated the presence of apical OH in di-octahedral hydro micas. Burns and White2 conclude from infra-red examination after hydrogen saturation and heating of LiNO3-treated muscovite that hydronium ions H3O+ replace interlayer cations,
Per Jørgensen, I. Th. Rosenqvist
openaire +2 more sources