Abstract
The systematic H/D substitution is a precious tool to obtain information on the dynamics of H-bonds. It is particularly useful in IR spectroscopy where H-bonds are at the origin of particularly intense and specific bands and where the particularly great value for the m{sub D}/m{sub H} ratio ensures strongly marked effects. In most H-bonded systems the effects of these substitutions are normal, in the sense that they are at the origin of bands having intensities, centers (of intensity) and widths smaller in D-bonds by a factor close to {radical}2 as compared to H-bonds. In some systems as carboxylic acid dimers, however, anomalous ratios of intensities are found upon such a substitution. Their origin is still obscure. Experimental results suggest that such anomalous ratios have much to do with the cyclic structure of these systems. It leads to stressing an important property of H-bonded cyclic structures which is that they seem necessary for having transfers of protons between molecules through H-bonds in a neutral aqueous medium (p{sub H}=7) at room temperature. The mechanism of such transfers of protons is still poorly known, but these transfers are now suspected to play a fundamental role in such widespread reactions as hydrolysis, peptide synthesis,
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Citation Formats
Marechal, Y.
Anomalous H/D isotope effect in hydrogen bonded systems: H-bonded cyclic structures and transfers of protons.
France: N. p.,
1993.
Web.
Marechal, Y.
Anomalous H/D isotope effect in hydrogen bonded systems: H-bonded cyclic structures and transfers of protons.
France.
Marechal, Y.
1993.
"Anomalous H/D isotope effect in hydrogen bonded systems: H-bonded cyclic structures and transfers of protons."
France.
@misc{etde_10109498,
title = {Anomalous H/D isotope effect in hydrogen bonded systems: H-bonded cyclic structures and transfers of protons}
author = {Marechal, Y}
abstractNote = {The systematic H/D substitution is a precious tool to obtain information on the dynamics of H-bonds. It is particularly useful in IR spectroscopy where H-bonds are at the origin of particularly intense and specific bands and where the particularly great value for the m{sub D}/m{sub H} ratio ensures strongly marked effects. In most H-bonded systems the effects of these substitutions are normal, in the sense that they are at the origin of bands having intensities, centers (of intensity) and widths smaller in D-bonds by a factor close to {radical}2 as compared to H-bonds. In some systems as carboxylic acid dimers, however, anomalous ratios of intensities are found upon such a substitution. Their origin is still obscure. Experimental results suggest that such anomalous ratios have much to do with the cyclic structure of these systems. It leads to stressing an important property of H-bonded cyclic structures which is that they seem necessary for having transfers of protons between molecules through H-bonds in a neutral aqueous medium (p{sub H}=7) at room temperature. The mechanism of such transfers of protons is still poorly known, but these transfers are now suspected to play a fundamental role in such widespread reactions as hydrolysis, peptide synthesis, etc... which may make them soon appear as being a crucial basic mechanism for reactivity of aqueous systems, particularly biological systems.}
place = {France}
year = {1993}
month = {Dec}
}
title = {Anomalous H/D isotope effect in hydrogen bonded systems: H-bonded cyclic structures and transfers of protons}
author = {Marechal, Y}
abstractNote = {The systematic H/D substitution is a precious tool to obtain information on the dynamics of H-bonds. It is particularly useful in IR spectroscopy where H-bonds are at the origin of particularly intense and specific bands and where the particularly great value for the m{sub D}/m{sub H} ratio ensures strongly marked effects. In most H-bonded systems the effects of these substitutions are normal, in the sense that they are at the origin of bands having intensities, centers (of intensity) and widths smaller in D-bonds by a factor close to {radical}2 as compared to H-bonds. In some systems as carboxylic acid dimers, however, anomalous ratios of intensities are found upon such a substitution. Their origin is still obscure. Experimental results suggest that such anomalous ratios have much to do with the cyclic structure of these systems. It leads to stressing an important property of H-bonded cyclic structures which is that they seem necessary for having transfers of protons between molecules through H-bonds in a neutral aqueous medium (p{sub H}=7) at room temperature. The mechanism of such transfers of protons is still poorly known, but these transfers are now suspected to play a fundamental role in such widespread reactions as hydrolysis, peptide synthesis, etc... which may make them soon appear as being a crucial basic mechanism for reactivity of aqueous systems, particularly biological systems.}
place = {France}
year = {1993}
month = {Dec}
}