Search results for "samarium"

Early lanthanide organometallic hydrides: electronic and steric control of the stability

2000

Abstract Steric and electronic effects on the stability of early lanthanide, neodymium and samarium, organometallic hydrides are discussed. The instability of (tmp)2SmH (tmp=tetramethylphospholyl) is attributed to electronic factors and the low stability of (tBuC5H4)2SmH is related to steric reasons. The analogous neodymium hydride (tBuC5H4)2NdH, could not be obtained, whereas the more hindered triethylborohydride was formed. Access to bisphospholyl bridged heterobimetallic ruthenium–lanthanide hydrides is also related to the size of the lanthanide atom. The bimetallic structures are accessible for lanthanides of ionic radii smaller than 1 A. The role of organometallic hydrides versus alkyl…

Ceria-based electrolytes prepared by solution combustion synthesis: The role of fuel on the materials properties

2016

Ce0.8Sm0.2O2 − xpowders were synthesized by solution combustion synthesis using citric acid, cellulose and sucrose as single, or intimately mixed, fuels. The powders were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, N2sorption at −196 °C, H2-temperature programmed reduction and thermogravimetric analyses. Textural properties of the powders were shaped by the peculiar employed fuel. The study of reducibility revealed that oxygen vacancies formation is mainly influenced by both parameters, specific surface area and total pore volume. The different tendency toward reduction played a key role in sintering under reducing atmosphe…

Preparation of Sm-loaded brookite nanoparticles and thin films

2010

CCDC 672291: Experimental Crystal Structure Determination

2010

Related Article: J.Chakraborty, A.Ray, G.Pilet, G.Chastanet, D.Luneau, R.F.Ziessel, L.J.Charbonniere, L.Carrella, E.Rentschler, M.S.El Fallah, S.Mitra|2009|Dalton Trans.||10263|doi:10.1039/b908910a

CCDC 254789: Experimental Crystal Structure Determination

2006

Related Article: M.Volpe, G.Bombieri, N.Marchini|2006|J.Alloys Compd.|408|1046|doi:10.1016/j.jallcom.2004.12.132

Cation Diffusion and Segregation at the Interface between Samarium-Doped Ceria and LSCF or LSFCu Cathodes Investigated with X-ray Microspectroscopy

2017

The chemical compatibility between electrolytes and electrodes is an extremely important aspect governing the overall impedance of solid-oxide cells. Because these devices work at elevated temperatures, they are especially prone to cation interdiffusion between the cell components, possibly resulting in secondary insulating phases. In this work, we applied X-ray microspectroscopy to study the interface between a samarium-doped ceria (SDC) electrolyte and lanthanum ferrite cathodes (La0.4Sr0.6Fe0.8Cu0.2O3(LSFCu); La0.9Sr0.1Fe0.85Co0.15O3(LSCF)), at a submicrometric level. This technique allows to combine the information about the diffusion profiles of cations on the scale of several micromet…

Influence of Outer-Sphere Anions on the Photoluminescence from Samarium(II) Crown Complexes.

2021

Three samarium(II) crown ether complexes, [Sm(15-crown-5)2]I2 (1), [Sm(15-crown-5)2]I2·CH3CN (2), and [Sm(benzo-15-crown-5)2]I2 (3), have been prepared via the reaction of SmI2 with the corresponding crown ether in either THF or acetonitrile in good to moderate yields. The compounds have been characterized by single crystal X-ray diffraction and a variety of spectroscopic techniques. In all cases, the Sm(II) centers are sandwiched between two crown ether molecules and are bound by the five etheric oxygen atoms from each crown ether to yield 10-coordinate environments. Despite the higher symmetry crystal class of 1 (R3c), the samarium center resides on a general position, whereas in 2 and 3 …

Catalytic activity of solvated and unsolvated lanthanide halides in Friedel–Crafts acylations

2000

Abstract Anhydrous lanthanide halides — chlorides and bromides — can act as homogeneous catalysts of Friedel–Crafts acylations. The catalytic activity is related to the solubility of these anhydrous salts. More soluble THF or dioxane (Diox.) neodymium and samarium adducts are more active catalysts.

Electron spectroscopy with the SAGE spectrometer

2016

A device called the SAGE (Silicon And GErmanium) spectrometer, designed for in-beam electron spectroscopy, is introduced in this work. A detailed description to the technical aspects of the device is given along with several examples of analytical procedures related to work done with the device. The radial ltering method and veto/add-back algorithms are tools for improving the quality of the electron-gamma data whilst the time-gate selection procedure helps in determining absolute internal conversion coe cients without reference points. Two very di erent types of experiments with results obtained from the electron data are introduced and analysed. Coulomb excitation is used to probe 154Sm a…

Evolution of quadrupole collectivity in N=80 isotones toward the Z=64 subshell gap: The B(E2;2+1→0+1) value of 142Sm

2015

It was shown that the evolution of the B(E2; 2+ 1 → 0+ 1 ) values in N = 80 isotones from Te to Nd is affected by the underlying subshell structure. This manifests itself in the observation of the local suppression of the B(E2) value at Z = 58 with respect to the neighboring nuclei 136Ba and 140Nd. To investigate this shell sensitivity toward the Z = 64 subshell gap, the B(E2; 2+ 1 → 0+ 1 ) value of the unstable nucleus 142Sm was measured utilizing the projectile Coulomb excitation technique. The radioactive ion beam (RIB) experiment was performed at the REX-ISOLDE facility at CERN. The B(E2) value of 32 (4) W.u. reflects the impact of the π(1g7/2 2d5/2) subshell closure at Z = 64 with resp…