A series of six new dyads consisting of a zinc or magnesium porphyrin appended to a platinum terpyridine acetylide complex via a para-phenylene bisacetylene spacer are described. Different substituents on the 4' position of the terpyridinyl ligand were explored (OC7H15, PO3Et2, and H). The ground-state electronic properties of the dyads are studied by electronic absorption spectroscopy and electrochemistry, and they indicate some electronic interactions between the porphyrin subunit and the platinum complex. The photophysical properties of these dyads were investigated by steady-state, time-resolved, and femtosecond transient absorption spectroscopy in N,N-dimethylformamide solution. Excitation of the porphyrin unit leads to a very rapid electron transfer (2-20 ps) to the nearby platinum complex followed by an ultrafast charge recombination, thus preventing any observation of the charge separated state. The variation in the rate of the photoinduced electron transfer in the series of dyads is consistent with Marcus theory. The results underscore the potential of the para-phenylene bisacetylene bridge to mediate a rapid electron transfer over a long donor-acceptor distance.

Copper(I) nitride (Cu 3 N) is deposited by CVD using copper(II) hexafluoroacetylacetonate (Cu(hfac) 2 ), ammonia, and water as precursors. The influences of process parameters on growth rate, phase content, chemical composition and morphology are studied. The introduction of water is found to increase film growth rate on the SiO 2 substrate. Films are deposited in the temperature range 250-550 -C. Single-phase Cu 3 N is obtained up to 400 -C. A phase mixture of Cu 3 N and Cu is obtained at 425 -C, while a temperature of 550 -C and above yields single-phase Cu. X-ray diffraction (XRD) confirms that Cu 3 N has the cubic, antiReO 3 -type structure; with a cell parameter in the range 3.805-3.816 Å . X-ray photoelectron spectroscopy (XPS) verifies the Cu 3 N stoichiometry. The films are free from impurities (below the detection limit of 1%) at a large excess of ammonia. Scanning electron microscopy (SEM) shows facetted grains, with the faces becoming more well-defined at higher temperatures.

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Soft x-ray emission spectroscopy was used to characterize the electronic structure of seven copper nitride films, one synthesized with atomic layer deposition (ALD) and six grown with chemical vapor deposition (CVD) at different preparation temperatures. Interpretation of the x-ray emission spectra was supported by calculations of the electronic structure for bulk pure Cu(3)N and Cu(3)N with: an excess of Cu atoms, oxygen or carbon impurities, and N vacancies. The calculations are shown to describe the experimental spectra quite well. Analysis of the x-ray spectra suggests that films grown in copper rich environments and above a cut-off temperature of approximately 360 °C have a growing fraction of copper enriched areas, while films prepared below this temperature do not have these areas with excess copper.