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InChI:InChI=1/C16H32O2.Cd/c1-2-3-4-5-6-7-8-9-10-11-12-13-14-15-16(17)18;/h2-15H2,1H3,(H,17,18);/p-1

Upstream product

• 57-10-3 1-hexadecylcarboxylic acid 
• 7440-43-9 cadmium 
• 10108-64-2 cadmium(II) chloride 

Relevant academic research and scientific papers

Characterisation of metal carboxylates by Raman and infrared spectroscopy in works of art

This work introduces the complementary use of μ-Raman and μ-Fourier transform infrared (IR) spectroscopy for the detection of specific carbon chains and cations for the identification of metal carboxylates within oil paint microsamples. Metal carboxylates (metal soaps) form naturally when free fatty acids react with metal cations and may also be found as additives or degradation products. Twenty-two metal carboxylates were synthesised, and their spectra assembled in a reference database. Metal salts of cations commonly present in oil paintings were used, including lead, zinc, calcium, cadmium, copper and manganese. The fatty acids selected were the saturated acids palmitic (C1 6:0) and stearic (C18:0) and the polyunsaturated oleic acid (C1 8:1). Azelaic acid (C9 diacid), a product resulting from autoxidation of polyunsaturated acids, was also included. Metal carboxylates were characterised by Raman and IR spectroscopy, and their structures were confirmed by X-ray diffraction. Raman and IR spectroscopy proved to be complementary techniques for a full identification of the metal carboxylates in complex aged paint. Raman enables the differentiation of the carbon chain length in the C-C stretching region (1120-1040 cm-1), and IR distinguishes the metal cation in the COO- stretching absorption region (1650-1380cm-1). Principal component analysis was applied to the spectra in order to facilitate a fast and accurate method to discriminate between the different metal carboxylates and to aide in their identification. Finally, spectra from case studies were successfully projected in the principal component analysis models built, enabling a higher confidence level for the identification of copper palmitate and copper azelate in two 19th-century Portuguese oil paintings.

Thioalkanoates as site-directing nucleating centers for the preparation of patterns of CdS nanoparticles within 3-D crystals and LB films of Cd alkanoates

A method is described for the preparation of hybrid organic/inorganic structures where the inorganic component comprises semiconductor nanoparticles aligned in periodic layers within three-dimensional (3-D) crystalline powders and Langmuir-Blodgett (LB) films. The preparation process comprises the organization of metal ions in the form of periodic arrays within 3-D crystals or the LB films, followed by a topotactic gas/solid reaction. The method is illustrated for the organization of CdS nanoparticles within alkanoic acids. The order of the nanoparticles is achieved by introducing site directing nucleation centers of Cd thioalkanoates within Cd alkanoates, in the form of solid solutions. The formed particles are attached to the organic matrix via -C(O)S-Cd-S- bonds. The structure of those supramolecular architectures has been characterized by a variety of complementary methods, including transmission electron microscopy (TEM) and electron diffraction (ED), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and other spectroscopic measurements.