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First time, the title compound is prepared by solid state reaction of stoichiometric amounts of PbO, PbF2 (slight excess), and TiO2 (Pyrex tubes, 823 K, 12 h). [ABSTRACT FROM AUTHOR]

An abstract of the article "Synthesis and CO2 Absorption Properties of Single-phase Li2CuO2 as a CO2 Absorbent," by Yusuke Matsukura and colleagues is presented.

The A2B2X6X′0.5-type pyrochlore Pb2Ti2O5.4F1.2 is prepared as a single phase by solid state reaction of stoichiometric amounts of PbO, PbF2, and TiO2 (evacuated Pyrex tubes, 873 K, 12 h). [ABSTRACT FROM AUTHOR]

A novel C 3 -symmetric propeller-shaped vanadium(IV/V) oxide cluster complex, [V 8 O 19 (4,4'- t Bubpy) 3 ] (V 8 '), has been synthesized from the reaction of the windmill-shaped vanadium(V) oxide cluster complex [V 8 O 20 (4,4'- t Bubpy) 4 ] (V 8 ) with PPh 3 under N 2 , whereas refluxing V 8 in methanol or ethanol under N 2 provides tetranuclear oxido(alkoxido)vanadium(IV/V) complexes [V 4 O 6 (OR) 6 (4,4'- t Bubpy) 2 ] [R = Me (V 4 '-Me) and Et (V 4 '-Et)]. The mixed-valent vanadium(IV/V) clusters V 8 ' and V 4 ' are converted back to V 8 under O 2 . Interconversions of V 4 ' and the oxido(alkoxido)vanadium(V) complexes [V 4 O 8 (OMe) 4 (4,4'- t Bubpy) 2 ] (V 4 ) and [V 7 O 17 (OEt)(4,4'- t Bubpy) 3 ] (V 7 -Et) are also presented.

The structure proposed for Li(11)Nd(18)Fe(4)O(39-δ) (Chen et al. Inorg. Chem. 2012, 51, 8073) on the basis of diffraction and Mössbauer spectral data is compared to that determined previously for Nd(18)Li(8)Fe(5)O(39) (Dutton et al. Inorg. Chem.200847, 11212) using the same techniques. The Mössbauer spectrum reported by Chen et al. has been reinterpreted. The newly refined spectral parameters differ significantly from the published values but are similar to those reported for Nd(18)Li(8)Fe(5)O(39). The relative areas of the three components indicate that iron cations occupy the 2a, 8e, and 16i sites in space group Pm3n, in disagreement with the model determined from neutron diffraction by Chen et al. in which only the 2a and 8e sites are so occupied. The relationship between Li(11)Nd(18)Fe(4)O(39-δ) and Nd(18)Li(8)Fe(5)O(39) is discussed, and it is proposed that the sample prepared by Dutton et al. is a kinetic product whereas the sample prepared by Chen et al. is the thermodynamically preferred product.

Polycrystalline samples of Ln(18)Li(8)Rh(5-x)Fe(x)O(39) (Ln = La, Nd; 0.5 < or = x < or = 5) have been synthesized by a solid-state method and studied by a combination of dc and ac magnetometry, neutron diffraction, and Mossbauer spectroscopy. All compositions adopt a cubic structure (space group Pm3n, a(0) approximately 12 A) based on intersecting 111 chains made up of alternating octahedral and trigonal-prismatic coordination sites. These chains occupy channels within a Ln-O framework. At low values of x, iron preferentially occupies the smaller (2a) of the two distinct octahedral sites as low-spin Fe(IV). The Rh(III) on the larger (8e) octahedral site is replaced by high-spin Fe(III). Nd-containing compositions having x > 1 show spin-glass-like behavior below approximately 5 K. La-containing compositions having x > 1 show evidence of a magnetic transition at approximately 8 K, but the nature of the transition is unclear. This contrasting behavior demonstrates that, although the structural chemistry of the two systems is essentially the same, the magnetic character of the Ln cations plays an important role in determining the properties of these compounds.

Polycrystalline samples of Nd(18)Li(8)Fe(5)O(39) and Nd(18)Li(8)Co(4)O(39) have been synthesized using a solid-state method and studied by a combination of neutron diffraction, direct and alternating current magnetometry, and, in the case of Nd(18)Li(8)Fe(5)O(39), Mossbauer spectroscopy. Both compounds adopt a cubic structure (space group Pm3n, a(0) approximately 11.9 A) based on intersecting 111 chains made up of alternating octahedral and trigonal-prismatic coordination sites. The Fe(4+) cations in Nd(18)Li(8)Fe(5)O(39) are found on only the smaller of the two distinct octahedral sites in the structure; Fe(3+) and Li(+) are disordered over the larger octahedral site and the trigonal-prismatic site. The Nd(3+) cations occupy sites between the chains. The smaller octahedral site is fully occupied by cobalt in Nd(18)Li(8)Co(4)O(39), with 25% of the larger octahedral sites being vacant; Li(+) is only found on the prismatic sites. Nd(18)Li(8)Fe(5)O(39) shows spin-glass-like behavior with a spin-freezing temperature of 5.75 K, whereas Nd(18)Li(8)Co(4)O(39) appears to order antiferromagnetically at 2.3 K. In both cases, the magnetic coupling involves the Nd(3+) sublattice.