Sn (II) oxide finds numerous applications in different fields such as thin film transistors1, solar cells2 and sensors.3 In this study we present the fabrication of tin monoxide SnO by using Sn (II) ketoacid oximate complexes as precursors. Tin (II) ketoacidoximates of the type [HON=CRCOO]2Sn where R= Me 1, R= CH2Ph 2, and [(MeON=CMeCOO)3Sn]- NH4 +.2H2O 3 were synthesized by in situ formation of the ketoacid oximate ligand. The crystal structures were determined via single crystal X- ray diffraction of the complexes 1-3 revealed square planar and square pyramidal coordination environments for the Sn atom. Intramolecular hydrogen bonding is observed in all the complexes. Furthermore, the complexes were characterized by Infrared (IR), Nuclear Magnetic Resonance (NMR) and elemental analysis. From thermogravimetric analysis of 1-3, it was found that the complexes decomposed in the range of 160 – 165 oC. Analysis of the gases evolved during decomposition indicated complete loss of the oximato ligand in one step and the formation of SnO. Spin coating of 1 on silicon or glass substrate show uniform coating of SnO. Band gaps of SnO films were measured and found to be in the range of 3.0 – 3.3 eV by UV-Vis spectroscopy. X-ray photoelectron spectroscopy indicated surface oxidation of the SnO film. Heating 1 above 140 oC in air gives SnO of size ranging from 10 – 500 nm and is spherical in shape. The SnO nanomaterial is characterized by powder X-ray diffraction(XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM).

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A series of novel triphenylstannyl-C, (triphenylstannyl)methyl- O- and (tributylstannyl)methyl-O- substituted pentofuranose compounds have been synthesised. Two methods were employed: (i) the reaction of triphenyltinlithium with derivatised and protected (or partially protected) carbohydrates, and (ii) the reactions of carbohydrate alkoxides with (iodomethyl)triphenyltin and (iodomethyl)tributylin. The solution structures of the triorganotin-carbohydrate compounds were investigated by 1H, 13C and 119Sn NMR spectroscopy. In solution all of the triorganotin-carbohydrates were shown to contain four-co-ordinate tin atoms. The solid-state structures were investigated by a combination of solid-state NMR spectroscopy and single-crystal X-ray diffraction. There were no major conformational changes between the two phases for any of the compounds. The molecular structures of methyl 5-deoxy-2,3- O-isopropylidine-5-triphenylstannyl-beta-D-ribofuranoside and 5-deoxy-1,1- O-isopropylidine-5-triphenylstannyl-alpha-D-xylofuranose were determined. Two different molecular conformations were identified for the former compound, and hydrogen-bonding between adjacent molecules was shown to be present in the latter case. The reactions of the triorganotin-carbohydrate compounds with iodine and bromine were studied. The results indicated that the rate of cleavage of butyl-tin bonds was much slower than the cleavage of phenyl-tin bonds. The reactivity of the tin-phenyl bond was found to depend greatly on the structure of the carbohydrate ligand. Evidence of increased co-ordination in solution was found for the mono-halo derivatives of methyl 5-deoxy-2,3-O-isopropylidine-5-triphenylstannyl-beta-D-ribofuranoside and 5-deoxy-1,2-O-isopropylidine-5-triphenylstannyl-alpha-D-xylofuranose. The molecular structures of 5-deoxy-5-iododiphenylstannyl-1,2-O-isopropylidine-alpha-D-xylofuranose and 5-deoxy-5-diiododiphenylstannyl-1,2-O-isopropylidene-alpha-D-xylofuranose were determined. In the solid-state the geometry about the tin atoms was found to be distorted trigonal bipyramidal.

Radioactive ion beams (RIBs) provide a method for studying the properties of increasingly exotic nuclei. For many nuclei, the intensity of the RIB available in the isotope separation on-line (ISOL) technique is limited by the relatively long delay time in the target/ion source system (TISS). New techniques are needed to decrease this delay time, thereby increasing the intensity of the RIBs available for study. The sulfide molecular sideband was discovered in 2001 as a way to greatly enhance the quality of Sn beams. Holdup measurements were performed at the Holifield Radioactive Ion Beam Facility (HRIBF) to determine the extent to which the delay of Sn in the TISS is improved by the introduction of sulfur. The results clearly demonstrate that SnS has a shorter delay time than Sn and indicate the improved release efficiency for short half-lives. The results also indicate that improvements to the formation and release of SnS molecules from the TISS are possible. To this end, modifications were made to the standard HRIBF design to improve the formation and release of molecules from the TISS. The modified TISS design will provide greater control over the TISS parameters by enabling independent and controlled heating of the transfer line and by moving the gas feed line so that it is inserted directly into the target holder. With these improvements, it should be possible to improve the release of Sn isotopes in the sulfide molecular sideband by enabling the formation of the molecule earlier in the release process and by increasing the probability that the molecule will form.

The growth of TiN on cemented carbide, deposited by chemical vapour deposition (CVD), was studied. Today TiN is used as a seeding layer between the cemented carbide and the following layer. Previous experiments have shown that the coverage is uneven on the cemented carbide surface showing pits with a different growth than the main part of the surface. These pits most likely occur on some of the WC surfaces. Therefore the growth and orientation relation between the two phases were examined. Cemented carbide specimens were deposited with TiN under two different pressures and with different deposition time to give a layer as thick as the seeding layer used in the production and one about ten times thicker to study growth after the whole surface had been covered. Two pre-treatments where used on the specimens; one which were polishing with diamond and the other where the specimens were boiled in acid to remove the binder phase and expose the WC surfaces. The specimens were studied using XRD and a SEM equipped with EDS and EBSD detectors. The pictures taken with SEM showed that initial growth occurred at grain boundaries and polishing scratches. It also showed that growth occurred on all surfaces, which were confirmed by EDS. Both processes showed about the same appearance in the thinner layers but very different appearance in the thicker. This was confirmed by XRD were the thinner layers showed about the same result while the thicker ones differ from one another. Thus further growth is dependent on the parameters of the CVD process and not the surface beneath. EBSD showed an orientation relation between TiN and WC crystals in both processes. The process at lower pressure gave much finer grains which were difficult to index with EBSD, giving results in only three points. The process at higher pressure gave coarser grains which were more easily indexed. The relations WC{0001}-TiN{110}, giving WC{101̅0}-TiN{100}, and WC{0001}-TiN{111}, giving WC{101̅0}-TiN{211}, could be seen in more than one point. These results are consistent with previous studies of the growth of TiC on WC. This comparison between TiC and TiN makes it possible to draw the conclusion that also Ti(C,N) should behave the same. It also shows an orientation relation that is consistent no matter what WC plane is on the surface. The poor growth and the pits depend on the growth orientation of TiN on each specific WC surface.

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