The feasibility of preparing Fe 2Àx Mn x P nanoparticles using the single-source precursors FeMn(CO) 8 (μ-PR 2 ) (R = Ph or R = H) has been investigated. The solution-based thermal decomposition of FeMn(CO) 8 (μ-PPh 2 ) in the presence of hexadecylamine and oleic acid resulted in the formation of FeO nanoparticles, while decomposition of FeMn(CO) 8 (μ-PH 2 ) under similar conditions yielded iron-rich Fe 2Àx Mn x P nanoparticles. Solventless decomposition of FeMn(CO) 8 (μ-PH 2 ) at 573 K resulted in the formation of hexagonal FeMnP, a structure generally observed only at temperatures above 1473 K. The role of surface stabilizing agents in the production of iron-rich Fe 2Àx Mn x P nanoparticles was examined through a series of experiments in which the type and quantity of stabilizers were varied, and evidence that oleic acid was responsible for the leaching or sequestration of manganese atoms was obtained. X-ray photoelectron spectroscopy (XPS) data acquired from the Fe 2Àx Mn x P nanoparticles and powder X-ray diffraction (PXRD) data from air-oxidized hexagonal FeMnP show that manganese is preferentially oxidized in these materials. The relatively high oxophilicity of manganese is believed to be a major contributor to the formation of iron-rich Fe 2Àx Mn x P nanoparticles prepared in solution. Alternative stabilizers to oleic acid were screened to identify a stabilizer that would promote nanoparticle growth without depletion of manganese. Of the various stabilizers studied, only oleic acid and tetrakis(decyl)ammonium bromide were able to promote substantial nanoparticle growth, but the use of these additives invariably resulted in the formation of iron-rich Fe 2Àx Mn x P nanoparticles.

A new method for the preparation of phase‐pure ferromagnetic Fe3P films on quartz substrates is reported. This approach utilizes the thermal decomposition of the single‐source precursors H2Fe3(CO)9PR (R = tBu or Ph) at 400 °C. The films are deposited using a simple, home‐built metal‐organic chemical vapor deposition (MOCVD) apparatus and are characterized using a variety of analytical methods. The films exhibit excellent phase purity, as evidenced by X‐ray diffraction, X‐ray photoelectron spectroscopy, and field‐dependent magnetization measurements, the results of which agree well with measurements obtained from bulk Fe3P. Using scanning electron microscopy and atomic force microscopy techniques, the films are found to have thicknesses between 350 and 500 nm with a granular surface texture. As‐deposited Fe3P films are amorphous, and little or no magnetic hysteresis is observed in plots of magnetization versus applied field. Annealing the Fe3P films at 550 °C results in improved crystallinity as well as the observation of magnetic hysteresis.

Six new precursors for lead sulfide nanoparticles were synthesized by the reaction of lead acetate, with picolinic (Hpic), 2,6-dipicolinic (H 2 dipic) or salicylic (H 2 sal) acid followed by the addition of thiourea (tu) or thiosemicarbazide (ths). The compounds are "[Pb(Hsal) 2 (tu) 2 ]" (1a), "Pb(Hsal) 2 -(ths, and 3b formed well-defined crystals and were characterized by single-crystal X-ray diffraction, while the remaining compounds were characterized spectroscopically and by elemental analyses. The precursors were decomposed in both aqueous and nonaqueous media leading to pure crystalline galena in all cases. Depending upon conditions truncated octahedra, dendrites, nanocubes, interlinked nanocubes, nanohexapods and cubes were obtained. To elucidate the effect of single-source precursors on the mechanism of growth of nanoparticles, we compared the decomposition results with PbS nanostructures synthesized from multiple-source precursors using lead acetate with thiourea or thiosemicarbazide.

The first heterobimetallic phosphide thin film containing iron, manganese, and phosphorus, derived from the single-source precursor FeMn(CO) (μ-PH ), has been prepared using a home-built metal-organic chemical vapor deposition apparatus. The thin film contains the same ratio of iron, manganese, and phosphorus as the initial precursor. The film becomes oxidized when deposited on a quartz substrate, whereas the film deposited on an alumina substrate provides a more homogeneous product. Powder X-ray diffraction confirms the formation of a metastable, hexagonal FeMnP phase that was previously only observed at temperatures above 1200 °C. Selected area electron diffraction on single crystals isolated from the films was indexed to the hexagonal phase. The effective moment of the films (μ =3.68 μ ) matches the previously reported theoretical value for the metastable hexagonal phase, whereas the more stable orthorhombic phase is known to be antiferromagnetic. These results not only demonstrate the successful synthesis of a bimetallic, ternary thin film from a single-source precursor, but also the first low temperature approach to the hexagonal phase of FeMnP.

Deprotonation of Fe(CO)4PRH2 and treatment with Mn(CO)5Br afforded the dinuclear complexes FeMn(CO)8(μ-PRH) (1a, R = H; 1b, R = Ph), which contain the relatively rare μ-PH2 and μ-PPhH functionalities. The heterometallic nature of these complexes was confirmed by mass spectrometry, and the molecular structures of 1a and 1b were determined by X-ray diffraction experiments. Deprotonation of 1b and subsequent addition of Mn(CO)5Br or AuPPh3Cl yielded the trinuclear complexes FeMn(CO)8[μ-PPh(Mn(CO)5)] (3a) and FeMn(CO)8[μ-PPh(AuPPh3)] (3b), both of which were characterized structurally and spectroscopically. Deprotonation of 1a at room temperature resulted in rapid coupling of the deprotonated product [2a] − with neutral 1a to form M+[FeMn(CO)8(μ3-PH)Mn(CO)4(μ-PH2)Fe(CO)4]− (M+ [4] − ) (M+ = Li+, Na+, K+), the formation of which was observed using in situ infrared spectroscopy. M+ [4] − was found to decompose upon solvent removal, and the structure of [4] − was elucidated by examination of spectroscopic data. The 1H NMR spectrum of [4] - was characterized by first-order [ABMX] and [AMX] spin systems, and ESI-MS data confirmed that [4] − was formed by direct coupling of [2a] − with 1a without concomitant fragmentation or loss of CO ligands. Deprotonation of 1a at lower temperatures slowed the coupling process, allowing for the metalation of the monomeric anion [2a] − by treatment with AuPPh3Cl, the product of which was found to decompose gradually in solution and rapidly upon concentration.