A series of lead(ii) alkylxanthates, [Pb(SCOR)] (R = ethyl (1), n-propyl (2), n-butyl (3), n-hexyl (4) or n-octyl (5)) have been prepared and explored as single source precursors for use in melt reactions to form lead sulfide. X-ray single crystal structures of (2), (3) and (4) were used along with previously reported structures to investigate the influence of structure and chain length on the materials produced. The complexes were decomposed at 150, 175 or 200 °C forming PbS nanocrystals as confirmed by XRD and TEM. Analysis by SEM shows that the choice of precursor had an influence on nanocrystal size with longer alkyl chains resulting in smaller cubic nanocrystals. In addition to cubes, anisotropic growth was observed from decomposition of compound (5).

Monodispersed iron cobalt oxide (Fe2CoO4) and iron manganese oxide (Mn0.43Fe2.57O4) nanoparticles have been synthesized using bimetallic pivalate clusters of [Fe2CoO(O2CtBu)6(HO2CtBu)3] (1), Co4Fe2O2(O2CtBu)10(MeCN)2] (2), and [Fe2MnO(O2CtBu)6(HO2CtBu)3] (3) respectively as single source precursors. The precursors were thermolyzed in a mixture of oleylamine and oleic acid with either diphenyl ether or benzyl ether as solvent at their respective boiling points of 260 or 300 °C. The effect of reaction time, temperature and precursor concentration (0.25 or 0.50 mmol) on the stoichiometry, phases or morphology of the nanoparticles were studied. TEM showed that highly monodispersed spherical nanoparticles of Fe2CoO4 (3.6 ± 0.2 nm) and Mn0.43Fe2.57O4 (3.5 ± 0.2 nm) were obtained from 0.50 mmol of 1 or 3, respectively at 260 °C. The decomposition of the precursors at 0.25 mmol and 300 °C revealed that larger iron cobalt oxide or iron manganese oxide nanoparticles were obtained from 1 and 3, respectively, whereas the opposite was observed for iron cobalt oxide from 2 as smaller nanoparticles appeared. The reaction time was investigated for the three precursors at 0.25 mmol by withdrawing aliquots at 5 min, 15 min, 30 min, 1 h, and 2 h. The results obtained showed that aliquots withdrawn at reaction times of less than 1 h contain traces of iron oxide, whereas only pure cubic iron cobalt oxide or iron manganese oxide was obtained after 1 h. Magnetic measurements revealed that all the nanoparticles are superparamagnetic at room temperature with high saturation magnetization values. XMCD confirmed that in iron cobalt oxide nanoparticles, most of the Co2+ cations are in the octahedral site. There is also evidence in the magnetic measurements for considerable hysteresis (>1T) observed at 5 K. EPMA analysis and ICP-OES measurements performed on iron cobalt oxide nanoparticles obtained from [Fe2CoO(O2CtBu)6(HO2CtBu)3] (1) revealed that stoichiometric Fe2CoO4 was obtained only for 0.50 mmol precursor concentration. All the nanoparticles were characterized by powder X-ray diffraction (p-XRD), transmission electron microscopy (TEM), inductively coupled plasma-optical emission spectroscopy (ICP-OES), electron probe microanalysis (EPMA), X-ray magnetic circular dichroism (XMCD), and superconducting quantum interference device (SQUID) magnetometry.

The iron pivalate clusters [Fe(3)O(O(2)C(t)Bu)(6)(H(2)O)(3)](O(2)C(t)Bu)·HO(2)C(t)Bu (1), [Fe(8)(OH)(4)(O(2)C(t)Bu)(12)(OC(6)H(4)C(6)H(5))(8)] (2) and [Fe(3)O(O(2)C(t)Bu)(6)(C(5)H(5)N)(3)] (3) have been used as single source precursors to synthesise iron oxide nanoparticles by a hot injection thermal decomposition method in oleylamine, hexadecanol, oleic acid, oleylamine/oleic acid with dodecanol or octyl ether as solvent. The effect of the different reaction parameters such as temperature, reaction time and capping agents on the phase and morphology were studied. The reaction time was studied for (1) by thermolysis in a mixture of oleylamine, oleic acid, hexadecanol and dodecanol (solvent) at 260 °C. The results obtained showed that a mixture of maghemite-C (Fe(2)O(3)) and magnetite (Fe(3)O(4)) were obtained for aliquots withdrawn for reaction times of less than 30 minutes whilst only magnetite was obtained after one hour. The nanoparticles were characterised by p-XRD, TEM and magnetic measurements. TEM showed that monodispersed magnetite particles were obtained when the precursor was injected at the boiling point of the solvent. The diameter of the monodispersed nanoparticles obtained by the thermolysis of [Fe(3)O(O(2)C(t)Bu)(6)(H(2)O)(3)](O(2)C(t)Bu)·HO(2)C(t)Bu (1) in oleylamine, hexadecanol, oleic acid with dodecanol or octyl ether as solvent were 4.3 ± 0.4 and 4.9 ± 0.5 nm respectively. Magnetic measurements revealed that all the particles are superparamagnetic.

The heterometallic pivalate clusters have been used as single source precursors to synthesise zinc ferrite or nickel ferrite nanoparticles. The different reaction parameters, magnetic properties and XMCD were studied.

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