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Thallium chemical shift referencing
1Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
Abstract:
Thallium chemical shifts are very sensitive to chemical and physical conditions. This makes accurate chemical shift referencing difficult. Therefore, chemical shifts are usually referenced to the 1H reference multiplied by a standard factor. However, past papers are referenced to TlNO3 solution in water at infinite dilution. The chemical shift of TlNO3 at infinite dilution is measured accurately and found to be -22.16 and 0.75 ppm for 203Tl and 205Tl, respectively relative to the standard frequency ratios to proton. The behavior of thallium chemical-shift with concentration and temperature are determined and discussed in relation to the degree of ionic association.
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