12036-05-4

Usage

InChI:InChI=1/2O.Pr/rO2Pr/c1-3-2

Upstream product

• 10028-15-6 ozone 
• 14797-55-8 Nitrate 
• 92206-38-7 ammonium acetate 
• 80937-33-3 oxygen 
• 7782-50-5 chlorine 
• 13709-46-1 praseodymium(III) fluoride 

Downstream Products

• 22541-14-6 praseodymium⁽³⁺⁾ 

Relevant academic research and scientific papers

Cooperative Jahn-Teller distortion in PrO2

We report neutron diffraction data on single crystal PrO2 which reveal a cooperative Jahn-Teller distortion at TD=120±2 K. Below this temperature an internal distortion of the oxygen sublattice causes the unit cell of the crystallographic structure to become doubled along one crystal axis. We discuss several possible models for this structure. The antiferromagnetic structure below TN=13.5 K is found to consist of two components, one of which shares the same doubled unit cell as the distorted crystallographic structure. We also present measurements of the magnetic susceptibility, the specific heat capacity, and the electrical conductivity of PrO2. The susceptibility data show an anomaly at a temperature close to TD. From the specific heat capacity data we deduce that the ground state is doubly degenerate, consistent with a distortion of the cubic local symmetry. We discuss possible mechanisms for this. The conductivity shows an activated behavior with an activation energy Ea=0.262±0.003 eV.

Research of thermal decomposition of hydrated methanesulfonates

Hydrated methanesulfonates Ln(CH3SO3) 3·nH2O (Ln=La, Ce, Pr, Nd and Yb) and Zn(CH 3SO3)2·nH2O were synthesized, The effect of atmosphere on thermal decomposition produ

X-ray absorption studies of CeO2, PrO2, and TbO2. I. Manifestation of localized and extended f states in the 3d absorption spectra

The 3d x-ray absorption spectra of CeO2, PrO2, and TbO2 show some interesting features. The main lines in these spectra are unusually broad. They are identified by comparison with the 3d-4f atomiclike multiplets observed in Z-1 elements. In these oxides, the positions and the similar form of a weaker structure which is systematically observed at about 35 eV above each main line indicate that it is due to the transitions to the extended f type of states. These observations demonstrate a specific behavior of the outermost f electron which differentiates these oxides from other intermediate-valence materials and from the Ce intermetallic compounds.

Chlorination of Pr2O3 and Pr6O11. Crystal structure, magnetic and spectroscopic properties of praseodymium oxychloride

The reactions of Pr2O3 and Pr6O11 with Cl2(g) were studied thermodynamically and experimentally, and proposed in the systems Pr2O3/Cl2(g) and Pr6O11/Cl2(g). A kinetic analysis was performed on Pr6O11 chlorination, which differs from with other light rare earth oxide chlorinations. The praseodymium oxychlorides obtained by full chlorination of Pr6O11 at 425 °C and 800 °C are different, being well characterized by X-ray diffraction, scanning electron microscopy, magnetic susceptibility measurements and X-ray photoelectron spectroscopy. The crystal structures of the oxychlorides were refined with the Rietveld method. The comparison between the theoretical magnetic moment of Pr3+ and the estimated magnetic moment in the praseodymium oxychloride obtained at 425 °C revealed the presence of Pr3+ and Pr4+, whereas no significant difference was observed between the theoretical and the experimental values of Pr3+ obtained for the praseodymium oxychloride prepared at 800 °C. These observations are consistent with the analyses in the X-ray photoelectron spectra for both oxychlorides. Finally, a general formula of PrO1+xCl is proposed for the oxychlorides synthesized at T 800 °C.

Orthorhombic HP-PrO2 - high-pressure synthesis and crystal structure

The high-pressure phase of PrO2 was synthesized under conditions of 5.5 GPa and 1000°C in a Walker-type multianvil apparatus. The crystal structure was determined on the basis of single-crystal X-ray diffraction data collected, at room temperature. The title compound. crystallizes in the orthorhombic α-PbCl2-type structure with the lattice parameters a = 637.6(3) pm, b = 384.4(2) pm, and c = 703.1(3) pm. The praseodymium ion is ninefold coordinated, the oxygen ions show either tetrahedral or square-pyramidal coordination spheres.

Study of Ce1-xPrxO2 pigments

The synthesis of new compounds based on CeO2, which can be used as pigments for colouring of ceramic glazes, is investigated in our laboratory. The optimum conditions for the syntheses of these compounds have been estimated and the pigments pre

Synthetic control to achieve lanthanide(III)/pyrimidine-4,6-dicarboxylate compounds by preventing oxalate formation: Structural, magnetic, and luminescent properties

Figure Persented: Control over the synthetic conditions in many metal/diazinedicarboxylato systems is crucial to prevent oxalate formation, since dicarboxylato ligands easily undergo degradation in the presence of metal salts. We report here an efficient route to obtain oxalato-free compounds for the lanthanide/pyrimidine-4,6-dicarboxylato (pmdc) system on the basis of the reaction temperature and nonacidic pH or oxygen free atmosphere. Two different crystal architectures have been obtained: {[Ln(μ-pmdc)1.5(H 2O)3]·xH2O}n (1-Ln) and {[Ln2(μ4-pmdc)2(μ-pmdc)(H 2O)2]·H2O}n (2-Ln) with Ln(III) = La-Yb, except Pm. Both crystal structures are built from distorted two-dimensional honeycomb networks based on the recurrent double chelating mode established by the pmdc. In compounds 1-Ln, the tricapped trigonal prismatic coordination environment of the lanthanides is completed by three water molecules, precluding a further increase in the dimensionality. Crystallization water molecules are arranged in the interlamellar space, giving rise to highly flexible supramolecular clusters that are responsible for the modulation found in compound 1-Gd. Two of the coordinated water molecules are replaced by nonchelating carboxylate oxygen atoms of pmdc ligands in compounds 2-Ln, joining the metal-organic layers together and thus providing a compact three-dimensional network. The crystal structure of the compounds is governed by the competition between two opposing factors: the ionic size and the reaction temperature. The lanthanide contraction rejects the sterically hindered coordination geometries whereas high-temperature entropy driven desolvation pathway favors the release of solvent molecules leading to more compact frameworks. The characteristic luminescence of the Nd, Eu, and Tb centers is improved when moving from 1-Ln to 2-Ln compounds as a consequence of the decrease of the O-H oscillators. The magnetic properties of the compounds are dominated by the spin-orbit coupling and the ligand field perturbation, the exchange coupling being almost negligible.

Kinetic analysis of dechlorination and oxidation of PrOCl by using a non-isothermal TG method

Thermal dechlorination and oxidation process of praseodymium oxychloride, PrOCl, was studied from the view point of reaction kinetics. On the basis of data of thermogravimetry under different oxygen partial pressures at various heating rates, a kinetic an

SOLVOLYTIC DISPROPORTIONATION OF MIXED-VALENCE COMPOUNDS L. Pr7O12.

Pr//7O//1//2 is an intermediate praseodymium oxide of mixed oxidation state. It is single phase with metal atoms occupying different types of crystallographic sites. In contact with dilute acid, among other solvents, the single-phase compound loses Pr**3*

Carboxylato-bridged 3D polymeric networks of Pr(III): Synthesis, crystal structure, magnetic property and thermal behavior

A novel polymeric carboxylato-bridged praseodymium(III) complex of fumarate, [Pr2(fum)3(H2O)4] ·5H2O (fum, fumarate dianion) has been synthesized and characterized by single-crystal X-ray diffraction studies, magnetic measurements and thermal studies. Single crystal X-ray structural determination reveals that it is a new porous three dimensional pillared layer framework with 1D channel for the accommodation of tetrameric water clusters. A preliminary treatment of the variable-temperature magnetic susceptibility using an expression including the ligand field effects and molecular field approximation leads to zJ′ = -1.60 cm-1, Δ = 0.5 cm-1 and g = 0.84, suggesting the existence of a weak antiferromagnetic coupling between the praseodymium ions.