Single molecule magnets on a gold surface: in situ electrospray deposition, x-ray absorption and photoemission

Single molecule magnets based on the dodecamanganese (III, IV) cluster with two different types of ligand (acetate and benzoate) have been studied on the Au(111) surface. Due to the non-volatile and fragile nature of the molecules, we have used ultra-high vacuum electrospray deposition to produce a series of surface coverages from a fraction of a monolayer to multilayer films in both cases. Synchrotron radiation based electron spectroscopy has been used to study the adsorption of the molecules on the Au(111) surface and the effect that this has on the oxidation states of the manganese atoms in the core. In both cases, reduction of the core is observed due to the interaction with the surface, to essentially the same extent despite substantial differences in the size and nature of the ligand shell.     

Lead-free electrostrictive bismuth perovskite ceramics with thermally stable field-induced strains

Electric field-induced strain (EFIS) properties of Bi_1/2(Na_0.82K_0.18)_1/2TiO₃ (BNKT) ceramics modified with Sr(K_1/4Nb_3/4)O₃ (SKN) have been investigated as functions of composition and temperature. BNKT ceramics near a phase boundary revealed the coexistence of ferroelectric rhombohedral and tetragonal phases, resulting in a typical ferroelectric butterfly-shaped bipolar S–E loop at room temperature, whose normalized strain (S_max/E_max) showed a significant temperature coefficient of 0.38 pm/V/K. However, 5 mol% SKN-modified BNKT ceramics revealed a typical electrostrictive behaviour with a thermally stable electrostrictive coefficient, Q₃₃ = 0.021 m⁴/C², which is almost comparable to that of Pb(Mg_1/3Nb_2/3)O₃ (PMN) ceramics that have been dominantly used as Pb-based electrostrictive materials over the last decades.     

Design of luminescent inorganic materials: new photophysical processes studied by optical spectroscopy

Recent spectroscopic results in the emerging area of transition-metal NIR-to-visible upconversion are related. The examples of Ti(2+)-, Re(4+)-, and Os(4+)-doped materials showing upconversion illustrate GSA/ESA, GSA/ETU, and photon avalanche multiphoton excitation mechanisms, respectively. Strategies for manipulation of such upconversion processes using the spectroscopic or magnetic properties of the host material are described. High-resolution low-temperature continuous-wave absorption and emission and time-resolved emission experiments combine to yield information about energy splittings, intensities, and excited-state dynamics, and assist in the design and development of luminescent materials showing novel multiphoton excitation properties.     

Trace elements in edible fats. VIII. Soybean oil “demetalization” with cation exchange resins

The effects of different solvents, degree of dilution, type of resin, and temperature were studied to determine the optimum conditions for “demetalization” of soybean oils with cation exchange resins. Prooxidant metals in crude soybean oils in acetone orn-hexane solutions can be effectively removed when passed through columns of a strong cation exchange resin. Supported by Grant No. FG-Sp-103-60 under Public Law 480. Agricultural Util. Res. Program. USDA.