Physical and Biophysical Chemistry
Division
Commission Molecular Structure and Spectroscopy
NMR Nomenclature: Nuclear Spin
Properties and Conventions for Chemical Shifts
A unified scale is recommended for reporting the NMR chemical shifts
of all nuclei relative to the 1H resonance of tetramethylsilane.
The unified scale is designed to provide a precise resonance frequency
X in a magnetic field in which the
1H resonance of TMS in dilute solution (< 1% by volume) in
chloroform is exactly 100 MHz. Referencing procedures are discussed,
including matters of practical application of the unified scale. Secondary
reference samples are recommended for each nucleus, and the relevant
values of X are listed, many of which
are the results of new measurements.
Some earlier recommendations relating to the reporting of chemical
shifts are endorsed, though a minor change to the definition of the
d scale is suggested. Relations between the
unified scale and recently published recommendations for referencing
in aqueous solutions (for specific use in biochemical work) are mentioned,
as well as the special effects of working in the solid state with magic-angle
spinning. In all, nine new recommendations relating to chemical shifts
are made.
Standardized nuclear spin data are presented in tabular form for the
stable (and some unstable) isotopes of all elements with nonzero quantum
numbers. The information given includes quantum numbers, isotopic abundances,
magnetic moments, magnetogyric ratios, receptivities, and, where appropriate,
quadrupole moments and linewidth factors.
> Download full text of the Provisional
Recommendations (pdf file - 231 KB)
Comments by 31 August 2001
To Prof. Robin K. Harris
Department of Chemistry
University of Durham
South Road,
Durham DH1 3LE, United Kingdom
Tel.: +44 191-374-3121
Fax: +44 191-386-1127
E-mail: [email protected]
> Project Description
