X-Ray Absorption Edges of Transition Metal Salts

Abstract Bis-2-thienyldiethylaminophosphane (C4H3S)2PNEt2 (1) is introduced as a ligand for late transition metal complexes ([(H3C4S)2PNEt2]nMXmLp), with M = Ni(II), Au(I), Cu(I), Pd(II), Ir(I), X = Cl, Br and L = NCMe, COD, (2-7). Reactions of 1 with the late transition metal salts NiCl2·dme, (Me2S)AuCl, CuCl, PdCl2(PhCN)2, and [Ir(COD)Cl]2 yield the complexes [{(H3C4S)2PNEt2}2 · NiCl2] (2), [(H3C4S)2PNEt2 · AuCl] (3) [(H3C4S)2PNEt2·CuCl(CH3CN)]2 (4), [{(H3C4S)2PNEt2}2 · PdCl2] (5), [{(H3C4S)2PNEt2}2·PdCl2]2 (6), and [(H3C4S)2PNEt2·IrCl(COD)] (7). In addition, the transformation of 1 to the valuable chlorine-substituted starting material (H3C4S)2PCl (8) and the related conversion of 8 to the secondary phosphane (H3C4S)2PH (9) is reported. The complexes 2-7 are stable under inert gas conditions and were characterized by single-crystal X-ray studies, NMR spectroscopy, and elemental analysis.

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ChemInform Abstract: Unusual Behaviour of the Thioether Function of the Ligand 1,8-Bis(3,5- dimethyl-1-pyrazolyl)-3,6-dithiaoctane (bddo) Towards Transition-Metal Salts. X-Ray Structures of a Green and a Red Modification of (Cu(bddo) Cl2).

ChemInform ◽

10.1002/chin.199102052 ◽

2010 ◽

Vol 22 (2) ◽

pp. no-no

Author(s):

W. G. HAANSTRA ◽

W. A. J. W. VAN DER DONK ◽

W. L. DRIESSEN ◽

J. REEDIJK ◽

J. S. WOOD ◽

...

Keyword(s):

Transition Metal ◽

Metal Salts ◽

X Ray ◽

Unusual Behaviour ◽

Transition Metal Salts

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Synthesis of New Derivatives of BEDT-TTF: Installation of Alkyl, Ethynyl, and Metal-Binding Side Chains and Formation of Tris(BEDT-TTF) Systems

Magnetochemistry ◽

10.3390/magnetochemistry7080110 ◽

2021 ◽

Vol 7 (8) ◽

pp. 110

Author(s):

Songjie Yang ◽

Matteo Zecchini ◽

Andrew Brooks ◽

Sara Krivickas ◽

Desiree Dalligos ◽

...

Keyword(s):

Metal Binding ◽

Tricarboxylic Acid ◽

Metal Salts ◽

Side Chain ◽

Side Chains ◽

Ethynyl Group ◽

X Ray ◽

Transition Metal Salts ◽

Alkyl Side Chains ◽

Derivatives Of

The syntheses of new BEDT-TTF derivatives are described. These comprise BEDT-TTF with one ethynyl group (HC≡C-), with two (n-heptyl) or four (n-butyl) alkyl side chains, with two trans acetal (-CH(OMe)2) groups, with two trans aminomethyl (-CH2NH2) groups, and with an iminodiacetate (-CH2N(CH2CO2−)2 side chain. Three transition metal salts have been prepared from the latter donor, and their magnetic properties are reported. Three tris-donor systems are reported bearing three BEDT-TTF derivatives with ester links to a core derived from benzene-1,3,5-tricarboxylic acid. The stereochemistry and molecular structure of the donors are discussed. X-ray crystal structures of two BEDT-TTF donors are reported: one with two CH(OMe)2 groups and with one a -CH2N(CH2CO2Me)2 side chain.

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Al-driven peculiarities of local coordination and magnetic properties in single-phase Alx-CrFeCoNi high-entropy alloys

Nano Research ◽

10.1007/s12274-021-3704-5 ◽

2021 ◽

Author(s):

Alevtina Smekhova ◽

Alexei Kuzmin ◽

Konrad Siemensmeyer ◽

Chen Luo ◽

Kai Chen ◽

...

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Magnetic Circular Dichroism ◽

Surface Region ◽

Face Centered Cubic ◽

X Rays ◽

X Ray ◽

High Entropy ◽

X Ray Absorption ◽

Absorption Edges

AbstractModern design of superior multi-functional alloys composed of several principal components requires in-depth studies of their local structure for developing desired macroscopic properties. Herein, peculiarities of atomic arrangements on the local scale and electronic states of constituent elements in the single-phase face-centered cubic (fcc)- and body-centered cubic (bcc)-structured high-entropy Alx-CrFeCoNi alloys (x = 0.3 and 3, respectively) are explored by element-specific X-ray absorption spectroscopy in hard and soft X-ray energy ranges. Simulations based on the reverse Monte Carlo approach allow to perform a simultaneous fit of extended X-ray absorption fine structure spectra recorded at K absorption edges of each 3d constituent and to reconstruct the local environment within the first coordination shells of absorbers with high precision. The revealed unimodal and bimodal distributions of all five elements are in agreement with structure-dependent magnetic properties of studied alloys probed by magnetometry. A degree of surface atoms oxidation uncovered by soft X-rays suggests different kinetics of oxide formation for each type of constituents and has to be taken into account. X-ray magnetic circular dichroism technique employed at L2.3 absorption edges of transition metals demonstrates reduced magnetic moments of 3d metal constituents in the sub-surface region of in situ cleaned fcc-structured Al0.3-CrFeCoNi compared to their bulk values. Extended to nanostructured versions of multicomponent alloys, such studies would bring new insights related to effects of high entropy mixing on low dimensions.

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