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The formation of lead carboxylates (lead soaps) has been identified as the cause of deterioration of hundreds of oil paintings. Soaps form when heavy metal-containing pigments, for example lead white and lead-tin yellow, react with saturated fatty acids in the oil medium. Understanding the mechanism of the reactions requires chemical information, which can be obtained with solid-state 207Pb, 119Sn and 13C NMR spectroscopy. Using the chemical-shift tensors determined by solid-state NMR we can gain structural insights on the coordination environment of the lead carboxylates and identify and quantify components in a paint film mixture. We have examined the spectroscopy of lead-containing pigments, lead carboxylates, and model paint films that were subjected to accelerated aging. We have also begun to investigate the dynamics of soap formation by 13C NMR spectroscopy. The NMR methods applied to the model paint systems could also be applied to other lead-containing materials.
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This content will become publicly available on June 16, 2026
Synthesis, Structure, and 199 Hg Chemical Shifts of Mercury 1,5,9‐trimesityldipyrromethene ( Mes DPM) Complexes
Abstract In this work, we describe the easy synthesis of mercury complexes with the 1,5,9‐trimesityldipyrromethene (MesDPM) ligand. The compounds were characterized using standard analytic methods such as NMR, IR, as well as UV/Vis spectroscopy. The molecular structures in solid state were determined by single‐crystal X‐ray diffraction analysis (SC‐XRD) experiments. In addition, the199Hg NMR chemical shifts were determined by measurements and quantum chemical calculations.
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- Award ID(s):
- 2055063
- PAR ID:
- 10614989
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 31
- Issue:
- 40
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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