We demonstrate two methods to improve the quality of organic depth profiling by C(60) sputtering using multilayered reference samples as part of a VAMAS (Versailles project on Advanced Materials and Standards) interlaboratory study. Sample cooling was shown previously to be useful in extending the useful depth over which organic materials can be profiled. We reinforce these findings and demonstrate that cooling results in a lower initial sputtering yield to approximately -40 degrees C, but the improvement in useful profiling depth continues as the sample is cooled further, even though there is no further reduction in the initial sputtering yield. We report, for the first time, the use of sample rotation in organic depth profiling and demonstrate that the initial sputtering yield at room temperature is maintained throughout the depth of the samples used in this study. Useful profiling depth and good depth resolution are both associated with a constant sputtering yield. The fact that rotation results in the maintenance of depth resolution underlines the fact that depth resolution is often limited by the development of ion-beam-induced topography. Constant sputtering yield results in a constant secondary-ion yield, after transient processes have occurred, and this allows simple quantification methods to be applied to organic depth profiling data.

For the organic memory device with vertically arranged electrodes, controlling the film‐packing to achieve highly oriented crystallite arrangement is critical but challenging for obtaining the satisfied performance. Here, the effect of backbone planarity on the crystallite orientation is studied. Two diketopyrrolopyrrole‐based small molecules (NI2PDPP and NI2FDPP) are synthesized with increasing planarity by furan substitution for phenyl rings. Upon thin‐film analysis by atomic force microscopy, X‐ray diffraction, and grazing‐incidence small‐angle X‐ray scattering, the orientations of these crystallites are demonstrated to be well controlled through tailoring molecular planarity. The highly planar NI2FDPP in film prefers out‐of‐plane crystallite orientation with respect to the substrate normal while the nonplanar NI2PDPP displays less ordered packing with a broad orientation distribution relative to the substrate. As a result, NI2FDPP‐based memory device exhibits superior multilevel performance. More importantly, the oriented crystallite arrangement favors uniformity in NI2FDPP thin film, thus, the device displays higher reproducibility of memory effects. This study provides an effective synthetic strategy for designing multilevel memory materials with favorable crystallite orientation.

Mu‐nick: The methyl iodide‐mediated ring opening of nickelalactones, which can be formed by oxidative coupling of carbon dioxide and ethylene at Ni0 complexes, induces β‐H elimination, producing methyl acrylate in yields of up to 56 %. This reaction is found to be very sensitive to the ligands coordinated to the central nickel atom.

We present the results of a VAMAS (Versailles project on Advanced Materials and Standards) interlaboratory study on organic depth profiling, in which twenty laboratories submitted data from a multilayer organic reference material. Individual layers were identified using a range of different sputtering species (C 60 n+ , Cs + , SF 5 + and Xe + ), but in this study only the C 60 n+ ions were able to provide truly 'molecular' depth profiles from the reference samples. The repeatability of profiles carried out on three separate days by participants was shown to be excellent, with a number of laboratories obtaining better than 5% RSD (relative standard deviation) in depth resolution and sputtering yield, and better than 10% RSD in relative secondary ion intensities. Comparability between laboratories was also good in terms of depth resolution and sputtering yield, allowing useful relationships to be found between ion energy, sputtering yield and depth resolution. The study has shown that organic depth profiling results can, with care, be compared on a day-to-day basis and between laboratories. The study has also validated three approaches that significantly improve the quality of organic depth profiling: sample cooling, sample rotation and grazing angles of ion incidence.

In this paper a convenient and universal strategy for preparing nanoring arrays of different compositions based on a colloidal‐crystal‐template strategy is reported. Large‐area arrays of polystyrene, magnetite, Au, Si, magnetite nanoparticle/polystyrene and Au/polystyrene double‐layer composite nanorings are prepared. Many kinds of nanoring structures, including Fe3O4 nanoparticle/polystyrene and Au/polystyrene double‐layer nanorings, can be released from the substrates, resulting in free‐standing composite nanorings, which might be used as self‐assembly building blocks and ultrasensitive bio‐ and chemical sensors.

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We present preliminary results of a VAMAS interlaboratory study on organic depth profiling, TWA2, sub-project A3 (d). A layered organic system was used to assess the repeatability and comparability of organic depth profiling. Nineteen respondents have provided sufficient data to demonstrate that the coefficients of variation for depth resolution, sputtering yield and relative secondary ion intensities are typically 5-10%. This can be as good as 2-3% with modern instruments, when using a stable sputtering ion current and careful procedures, which approaches the limits set by the samples themselves. The respondents have also demonstrated three methods to improve the quality of depth profiling for this system, namely, sample rotation, cooling to at least −80• C and grazing incidence angles for the sputtering ion.

M 13 9PL , UK Oxyethylene/oxypropylene block copolymers were prepared with almost identical overall compositions (40 wt.% E) and molecular weights (M, = 2900) but different block structures, i.e. diblock E2,P2, and triblock E,4P30E,4. Their micellar and surface properties were studied by static and dynamic light scattering and surface tension. At a given temperature, the surface acitivity, the c.m.c., the molar micellar weight and the micellar size did not differ within the uncertainties of their determination. The only significant difference was in the area per molecule in the surface monolayer, wherein the diblock copolymer was more closely packed than the triblock copolymer.