Four new adducts catena-O,O′-glutaratotriphenylstannate, (Me4N)2O2C(CH2)3CO2×4SnPh3Cl (1), (Me4N)2O2C(CH2)3CO2×3SnPh3Cl (2), (SnPh3)2O2C(CH2)3CO2×SnPh3Cl (2′) and (Cy2NH2)2O2C(CH2)3CO2×SnPh3Cl (3), ...have been isolated from the reactions carried out in solution. The compounds have been characterized by FT-IR and Mössbauer spectroscopies except for 2’ whose structure is proposed on the basis of FT-IR data. Overall, the spectra studies sheew existence of several caracteristic bands such as υ (C=O), υ (CO2–), υ (Sn–O), υ (Sn–Cl), vibrations of glutarate ions, and the intense doublet showing the presence of phenyl groups. In the solid state, the suggested structures are discrete or of infinite chain. In this work, the geometry at Sn centers, trigonal bipyramidal or tetrahedral, is ascertained by the Mössbauer parameters. The glutarate ions exhibit a monodentate, tridentate or tetradentate coordination behavior towards the Sn atoms.
•A new honeycomb ordered layered oxide Na3LiFeSbO6 was synthesized.•This compound crystallizes in the C2/c space group.•Disorder in the honeycomb arrangement of Li and Fe is present.
A new compound ...Na3LiFeSbO6 has been synthesized by conventional solid state methods and investigated using X-ray diffraction, DC magnetic susceptibility, 57Fe Mössbauer spectroscopy and optical measurements. This compound crystallizes in a monoclinic unit cell and is related to a family of honeycomb ordered layered oxide materials where Na+ fills octahedral interlayer sites between Li1/3Fe1/3Sb1/3O2 slabs of edge sharing octahedra. Each SbO6 octahedron is surrounded by LiO6 and FeO6 octahedra creating a honeycomb arrangement within the slabs. Powder X-ray diffraction indicates the presence of stacking faults. This compound exhibits Curie–Weiss behavior at high temperatures and the effective magnetic moment verifies the presence of high spin Fe3+. The 57Fe Mössbauer spectroscopy confirms Fe3+ in an octahedral position and indicates disorder in the arrangement of LiO6 and FeO6 octahedra in the Li1/3Fe1/3Sb1/3O2 slabs.
Four new carboxyalkylphosphonate SnR2 residue (R = Me, Ph, Bu) containing adducts and derivatives i.e. {(Cy2NH2)3(O2CCH2PO3)(SnBu2Cl2)} (1), {(SnMe2Cl)(O2CCH2PO3H2)4Cy2NH2Cl} (2), ...{(Me4N)(SnPh2Cl)O2C(CH2)2 PO3H(SnPh2)O2C(CH2)2PO3H} (3) and {(Cy2NH2)2(O2CCH2PO3H)(SnPh2Cl2)2} (4), have been synthesized from one-pot reactions carried out in solution. All compounds have been investigated by spectral techniques (infrared and Mossbauer). The spectral studies have evidenced presence of several characteristic bands, especially υ (C=O), υ (OH), υ (CO2- ), υ (PO32- ) vibrations coming from carboxyalkylphosphonate ions, with wide absorption due to the NH2 groups coming from the dicyclohexylammonium counter ion (for 1, 2 and 4) and the intense doublet which show the presence of phenyl groups (for 3 and 4). In the solid state, the proposed structures are discrete or of infinite chain however hydrogen bonding patterns may occur. Event in this investigation is the presence, for compound 3, of two types of arrangement at Sn centers viz. an octahedron and a trigonal bipyramidal whose presence are ascertained by the Mossbauer parameters. The neutral or acidic carboxyalkylphosphonate ions exhibit a diversity of coordination behavior towards the Sn atoms: monochelating (carboxylate and phosphonate O-donor), monochelating through the carboxylate and unidentate coordinating O-donor through the phosphonic acid or acidic phosphonate, bichelating with chelations from carboxylate and acidic phosphonate, and unidentate from both the carboxylate and phosphonic acid.
In the orthorhombic manganites o-RMnO3, where R is a heavy rare earth (R = Gd-Yb), the Mn3+ sublattice is known to undergo two magnetic transitions. The low temperature phase has an antiferromagnetic ...structure (collinear or elliptical), which has been well characterized by neutron diffraction in most of these compounds. The intermediate phase, occurring in a narrow temperature range (a few K), is documented for R = Gd–Ho as a collinear modulated structure, incommensurate with the lattice spacings. We report here on a 57Fe Mössbauer study of 2% 57Fe doped o-YbMnO3, where the spin only Fe3+ ion plays the role of a magnetic probe. From the analysis of the shape of the magnetic hyperfine Mössbauer spectra, we show that the magnetic structure of the intermediate phase in o-YbMnO3 (38.0 K < T < 41.5 K) is also modulated and incommensurate.
Tin phosphate glasses in the SnO–P
2
O
5
binary diagram have been prepared by using a domestic microwave-heating device. Microwaves provide an extremely facile and automatically ...temperature-controlled route to the synthesis of glasses due to the specific dielectric properties of each chemical composition. Typical melting time is no longer than 10 min, limiting the oxidation of Sn
2+
and the melt can be quenched into glass. The glass transition temperature increases with the SnO content confirming the depolymerization of the vitreous network, as expected by the relative fraction of the different Q
n
structural units deduced from NMR experiments. Concerning the mechanical properties, the Vickers hardness and the fracture toughness decrease while the thermal expansion coefficient and the different elastic moduli remain constants. These results confirm that those characteristics are not very sensible to structural considerations. On the contrary, the chemical durability of Sn
2
P
2
O
7
, determined from the weight loss method, is 300 times higher than that of Sn(PO
3
)
2
. Furthermore, Sn
2
P
2
O
7
is the only glass composition that exhibits a devitrification phenomenon leading to the low-temperature phase of the crystalline tin(II) pyrophosphate.
In this work, two different laterites (iron contents of 13.07 and 49.34 wt%, respectively, for lateritic clay, LAC, and iron-rich laterite, LAI) were selected and calcined at 600 °C. The obtained ...calcined laterites, namely LAI600 and LAC600, were separately mixed with an alkaline solution (silicate modulus of 1.35) or an acidic solution (phosphoric acid solution at pH ≤ 2) for the synthesis of inorganic polymer products. The fabricated products were cured at 20 °C (ambient) and 40 °C (oven). The obtained results showed that the compressive strength of each series of alkaline-based inorganic polymer binder increased with ageing time (7 and 28 days) for room temperature curing, while the reverse trend was noted for oven-cured specimens. The best mechanical performance was obtained when using a phosphoric acid solution, 38 and 52 ± 1 MPa; 62 and 65 ± 1 MPa at 28 days for LAC and LAI respectively. It appeared that a higher iron content within the laterite contributed to an increase in the compressive strength under acidic conditions (LAI (59 MPa) > LAC (48 MPa)) compared to the behavior obtained under alkaline conditions (LAI (6 MPa) < LAC (29 MPa)). Accordingly, the acidic products exhibited a dense structure (with lower porosity) and contained amorphous iron/aluminium phosphate phases such as berlinite (FePO4), iron hydrogen phosphate hydrate (Fe3H15(PO4)8·4H2O), ferrowyllieite (AlFe2Na2(PO4)3) and sodium iron phosphate (Na3Fe2(PO4)3) arising from the alteration of iron minerals in an acidic medium, confirmed by Mössbauer spectroscopy and electron paramagnetic resonance spectroscopy.
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