Chemical Shifts

Some articles on chemical shifts, chemical shift, shift, shifts:

Proton NMR - Chemical Shifts
... Chemical shift values, symbolized by δ, are not precise, but typical - they are to be therefore regarded mainly as a reference ... The exact value of chemical shift depends on molecular structure and the solvent, temperature, magnetic field in which the spectrum is being record and other neighboring functional groups ... These cause a downfield shift of approximately 2-4 ppm for H atoms on Cα and of less than 1-2 ppm for H atoms on Cβ ...
Carbon-13 NMR - Implementation
13C chemical shifts follow the same principles as those of 1H, although the typical range of chemical shifts is much larger than for 1H (by a factor of about 20) ... The chemical shift reference standard for 13C is the carbons in tetramethylsilane (TMS), whose chemical shift is considered to be 0.0 ppm ... Typical chemical shifts in 13C-NMR ...
Nuclear Magnetic Resonance Spectroscopy - Basic NMR Techniques - Chemical Shift
... therefore gives a locator number called the "chemical shift" with units of parts per million ... In general, chemical shifts for protons are highly predictable since the shifts are primarily determined by simpler shielding effects (electron density ... The chemical shift provides information about the structure of the molecule ...
Phosphorus-31 NMR Spectroscopy - Applications in Chemistry - Chemical Shifts
... The ordinary range of chemical shifts ranges from abut δ250 to -δ250, which is much wider than typical for 1H NMR ... Unlike 1H NMR spectroscopy, 31P NMR shifts are primarily not determined by the magnitude of the diamagnetic shielding, but are dominated by the so-called paramagnetic shielding tensor (un ... Illustrative of the effects lead to big changes in chemical shifts, the chemical shifts of the two phosphate esters (MeO)3PO (δ2.1) and (t-BuO)3PO (δ-13.3) ...
Tetramethylsilane - Uses in NMR Spectroscopy
... the accepted internal standard for calibrating chemical shift for 1H, 13C and 29Si NMR spectroscopy in organic solvents (where TMS is soluble) ... The chemical shift of this singlet is assigned as δ 0, and all other chemical shifts are determined relative to it ... The chemical shift of this singlet is also set to be δ 0 in the 13C spectrum, and all other chemical shifts are determined relative to it ...

Famous quotes containing the words shifts and/or chemical:

    I have rather a strange objection to talking from the back platform of a train.... It changes too often. It moves around and shifts its ground too often. I like a platform that stays put.
    Woodrow Wilson (1856–1924)

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    Norman Mailer (b. 1923)