We have employed melt-spinning method to produce Ni sub(2)MnSn-based half-metallic Heusler alloy. It allows fast and simple production of large amount of materials in a single production step ...avoiding high temperature post-production annealing. Microstructural, magnetic and spin polarization study of Ni sub(2)MnSn ribbon is used for characterization. SEM analysis reveals the polycrystalline structure with the columnar crystals grown perpendicularly to the ribbon plane. A single-phase austenite with L2 sub(1) structure was confirmed by X-ray. Magnetic measurements shows the ordinary ferromagnetic behavior with Curie temperature 344 K and magnetic moment 4.08 mu sub(B)/f.u. Particular crystal structure leads to the well defined anisotropy having an easy plane in the ribbon's plane. Finally, the spin polarization parameter P sub(0) estimated by Point-Contact Andreev-reflection Spectroscopy is varying in the range 40-70% for Ni sub(2)MnSn which is comparable with other values reported earlier for other Heusler alloys.
Synthesis and characterization of a series of novel {Zn(Δ-cyclen)(HGly)}{Zn(Λ-cyclen)(HGly)}(ClO
4)
4
·
2H
2O (
1), {Zn(Δ-cyclen)(
S-HPhe)}{Zn(Λ-cyclen)(
S-HPhe)}(ClO
4)
4 (
2) and Zn(Δ-cyclen)(
...S-HAla)(ClO
4)
2 (
3) complexes are reported and non-covalent interactions were used for the conformation changes description. In addition to the TRANS-I +++ configuration we described two different isomers in the case of unmodified Zn–cyclen–aminoacid (Gly, Ala, Phe) complexes. Moreover, work also deals with the correlation between spectral and structural properties of the prepared complexes and their thermal stability.
Synthesis and characterization of a series of novel Zn–cyclen–aminoacid complexes are reported and non-covalent interactions were used for the conformation changes description. In addition to the TRANS-I +++ (same position of NH hydrogen atoms in both isomers) configuration we observed two different isomers in the case of the {Zn(Δ-cyclen)(HGly)}{Zn(Λ-cyclen)(HGly)}(ClO
4)
4
·
2H
2O (
1), {Zn(Δ-cyclen)(
S-HPhe)}{Zn(Λ-cyclen)(
S-HPhe)}(ClO
4)
4 (
2) and Zn(Δ-cyclen)(
S-HAla)(ClO
4)
2 (
3) complexes with pentacoordinated zinc atom. Moreover, work also deals with the correlation between spectral and structural properties of the prepared complexes and their thermal stability.
Potentiometric titrations and (1) H NMR spectroscopic studies of amino acids binding to the ZnL(2+) -complex where L=cyclen in aqueous solution provide information concerning complexing species ...identity, their stability, and coordination mode declaration. The amino acids form stable ternary ZnL(HL(n))(2+) and ZnL(L(n))(+) complexes. The observations indicate bidentate coordination mode of the deprotonated amino acids, involving both the amine and the carboxylate functions to the ZnL(2+) complex in pH region of about 7.5-9.5. The determined stability constants indicate that ZnL(2+) complex is a very efficient receptor for simple amino acids such as glycine and alanine.
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