The challenges associated with synthesizing porous materials mean that new classes of zeolites (zeotypes)-such as aluminosilicate zeolites and zeolite analogues-together with new methods of preparing known zeotypes, continue to be of great importance. Normally these materials are prepared hydrothermally with water as the solvent in a sealed autoclave under autogenous pressure. The reaction mixture usually includes an organic template or 'structure-directing agent' that guides the synthesis pathway towards particular structures. Here we report the preparation of aluminophosphate zeolite analogues by using ionic liquids and eutectic mixtures. An imidazolium-based ionic liquid acts as both solvent and template, leading to four zeotype frameworks under different experimental conditions. The structural characteristics of the materials can be traced back to the solvent chemistry used. Because of the vanishingly low vapour pressure of ionic liquids, synthesis takes place at ambient pressure, eliminating safety concerns associated with high hydrothermal pressures. The ionic liquid can also be recycled for further use. A choline chloride/urea eutectic mixture is also used in the preparation of a new zeotype framework.

Aluminum I 2100Ionic Liquids and Eutectic Mixtures as Solvent and Template in Synthesis of Zeolite Analogues. -The synthesis of different aluminophosphate zeolite analogues using 1-ethyl-3-methyl imidazolium bromide or a choline chloride/urea eutectic mixture as both solvent and template is demonstrated. Because of the vanishingly low vapor pressure of ionic liquids, synthesis takes place at ambient pressure, eliminating safety concerns associated with high hydrothermal pressures. The ionic liquid can also be recycled for further use. The structures of (II) (triclinic, space group P1; novel structure type), (III) (orthorhombic, Pna21, Z = 4; novel zeotype), (IV) (orthorhombic, Ibm2; AlPO-11 type), and (V) (triclinic, P1; AlPO-34 type) are determined by single crystal XRD. -(COOPER, E. R.; ANDREWS, C. D.; WHEATLEY, P. S.; WEBB, P. B.; WORMALD, P.; MORRIS, R. E.; Nature (London, UK) 430 (2004) 7003,

Understanding and manipulating the two half‐reactions of photoinduced electron reduction and hole oxidation are key to designing and constructing efficient photocatalysts. Here, how the spatial distribution of the heteroatom modulates photocatalytic reduction (hydrogen evolution) and oxidation (oxygen evolution) reaction preferences is investigated by moving boron from the core to the shell of an anatase TiO2 microsphere along [001] via thermal diffusion control. The preference towards photocatalytic hydrogen and oxygen producing reactions from splitting water can be switched by creating a shell with an interstitial Bσ+ (σ ≤ 3) gradient in the TiO2 microsphere. This switching stems from the downward shift of electronic band edges of the shell by a band bending effect that originates from the extra electrons coming from the interstitial Bσ+. These results create new opportunities for designing and constructing efficient photocatalysts by spatial heteroatom engineering.

We present a systematic study on the effect of starting species, gas composition, temperature, particle size and duration of heating upon the molecular and stable isotope composition of high density (mangrove) and low density (pine) wood. In both pine and mangrove, charcoal was depleted in δ 13 C relative to the starting wood by up to 1.6‰ and 0.8‰ respectively. This is attributed predominantly to the progressive loss of isotopically heavier polysaccharides, and kinetic effects of aromatization during heating. However, the pattern of δ 13 C change was dependant upon both starting species and atmosphere, with different structural changes associated with charcoal production from each wood type elucidated by Solid State 13 C Nuclear Magnetic Resonance Spectroscopy. These are particularly evident at lower temperatures, where variation in the oxygen content of the production atmosphere results in differences in the thermal degradation of cellulose and lignin. It is concluded that production of charcoal from separate species in identical conditions, or from a single sample exposed to different production variables, can result in significantly different δ 13 C of the resulting material, relative to the initial wood. These results have implications for the use of charcoal isotope composition to infer past environmental change.

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Chlorotrifluoroethylene (CTFE) and ethyl vinyl ether (EVE) were reacted under radical conditions to produce the poly(CTFE-co-EVE) alternating copolymer, and a full 13 C, 1 H, and 19 F NMR structural interpretation is offered. All spectra were characterized by broad signals resulting from the overlapping of different chemical shifts. This observation was rationalized by considering a complex mixture of diastereomerically related compounds, hence allowing an average assignment to be determined. A density functional theory (DFT) computational study of the isotropic magnetic shieldings with the GIAO and CSGT methods was performed to explore the diasteriomeric relationships between the single building blocks and their mutual influences along the polymer chain. The calculated results totally support the assignment of the experimental chemical shifts of two diasteriomeric sets of resonances indicating chiral center inversion, and not spin-spin J coupling interactions, as the main cause of spectral complexity. 13 C, and 19 F NMR spectra, obstructing the determination of 1 H-19 F coupling constants and detailed structure of the copolymer. Furthermore, few detailed analyses using multinuclear 19 F, 13

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