A new platinate was recently discovered when Nd2O3 was explored as a platinum capture material in the Ostwald process, formed by a direct reaction between gaseous PtO2 and Nd2O3. The crystal structure of this new platinate and its composition, Nd10.67Pt4O24, are here reported for the first time. The compound is synthesized either by a direct reaction between PtO2(g) and Nd2O3 or by the citric acid chemical route. Based on 3-dimensional electron diffraction data and Rietveld refinement of high-resolution synchrotron and neutron powder diffraction data, we describe its crystal structure in space group I41/a. The compound is structurally related to the Ln11-x Sr x Ir4O24 (Ln = La, Pr, Nd, and Sm) phases with a double perovskite (A2BB'O6)-like crystal structure with A-site cation deficiency. Owing to the fixed oxidation state of Pt(IV), two of the four Nd sites are partly occupied to provide charge neutrality, with Nd4 taking a split position. On heating, Nd10.67Pt4O24 decomposes into Nd2O3 and Pt. A plateau in the thermogravimetric curves measured in 33 vol % O2 in N2 indicates the presence of an intermediate Pt(II) phase at around 960 °C, probably isostructural with La4PtO7.

Center for Materials Science and Nanotechnology Department of Chemistry University of Oslo Oslo N 0315 Norway

Department for Hydrogen Technology Institute for Energy Technology P O Box 40 Kjeller NO 2027 Norway

Institute of Physics of the CAS Na Slovance 1999 2 Prague 8 182221 Czech Republic

Zobrazit více v PubMed

Zhou H.; Wiebe C. R. High-Pressure Routes to New Pyrochlores and Novel Magnetism. Inorganics 2019, 7, 49.10.3390/inorganics7040049. DOI

Hoekstra H. R.; Gallagher F. Synthesis of some pyrochlore-type oxides of platinum(IV) at high pressure. Inorg. Chem. 1968, 7, 2553–2557. 10.1021/ic50070a017. DOI

Hoekstra H. R.; Siegel S.; Gallagher F. X. .Reaction of Platinum Dioxide with Some Metal Oxides. Platin. Group Met. Compd; Rao U. V., Ed.; American Chemical Society: Washington, D.C., 1971; pp 39–53.10.1021/ba-1971-0098.ch004 DOI

Ostorero J.; Makram H. Single crystal growth of some pyrochlore type compounds of platinum(IV) at low pressure. J. Cryst. Growth 1974, 24–25, 677–678. 10.1016/0022-0248(74)90404-7. DOI

Morosan E.; Fleitman J. A.; Huang Q.; Lynn J. W.; Chen Y.; Ke X.; Dahlberg M. L.; Schiffer P.; Craley C. R.; Cava R. J. Structure and magnetic properties of the Ho2Ge2O7 pyrogermanate. Phys. Rev. B 2008, 77, 224423.10.1103/PhysRevB.77.224423. DOI

Für Krist. - Cryst. Mater. 1997, 212, 137.10.1524/zkri.1997.212.2.137. DOI

Welch P. G.; Paddison J. A. M.; Le M. D.; Gardner J. S.; Chen W.-T.; Wildes A. R.; Goodwin A. L.; Stewart J. R. Magnetic structure and exchange interactions in the Heisenberg pyrochlore antiferromagnet Gd2Pt2O7. Phys. Rev. B 2022, 105, 094402.10.1103/PhysRevB.105.094402. DOI

Cruickshank K. M.; Glasser F. P. Rare earth—platinum group mixed metal oxide systems. J. Alloys Compd. 1994, 210, 177–184. 10.1016/0925-8388(94)90135-X. DOI

Ouchetto K.; Archaimbault F.; Choisnet J.; Et-Tabirou M. New ordered and distorted perovskites: the mixed platinates Ln2MPtO6 (Ln = La, Pr, Nd, Sm, Eu, Gd; M = Mg, Co, Ni, Zn). Mater. Chem. Phys. 1997, 51, 117–124. 10.1016/S0254-0584(97)80279-9. DOI

Hansen T. J.; Macquart R. B.; Smith M. D.; zur Loye H.-C. Crystal growth and structures of three new platinates: Ln3NaPtO7 (Ln = La, Nd) and La4PtO7. Solid State Sci. 2007, 9, 785–791. 10.1016/j.solidstatesciences.2007.06.014. DOI

Hessevik J.; Carlsen C. S.; Bestul O. K.; Waller D.; Fjellvåg H.; Sjåstad A. O. Oxides for Pt Capture in the Ammonia Oxidation Process—A Screening Study. Reactions 2025, 6 (1), 13.10.3390/reactions6010013. DOI

Hessevik J.; Fjellvåg A. S.; Iveland O.; By T.; Skjelstad J.; Waller D.; Fjellvåg H.; Sjåstad A. O. LaNiO3 as a Pt catchment material in the ammonia oxidation process. Mater. Today Commun. 2022, 33, 104084.10.1016/j.mtcomm.2022.104084. DOI

Ferreira T.; Smith M. D.; zur Loye H.-C. A Family of A-Site Cation-Deficient Double-Perovskite-Related Iridates: Ln9Sr2Ir4O24 (Ln = La, Pr, Nd, Sm). Inorg. Chem. 2018, 57, 7797–7804. 10.1021/acs.inorgchem.8b00887. PubMed DOI

Bramnik K. G.; Miehe G.; Ehrenberg H.; Fuess H.; Abakumov A. M.; Shpanchenko R. V.; Pomjakushin V. Yu.; Balagurov A. M. Preparation, Structure, and Magnetic Studies of a New Sr11Re4O24 Double Oxide. J. Solid State Chem. 2000, 149, 49–55. 10.1006/jssc.1999.8493. DOI

Jeitschko W.; Mons H. A.; Rodewald U. C.; Möller M. H. The Crystal Structure of the Potential Ferroelectric Calcium Rhenate(VI, VII) Ca11Re4O24 and its Relation to the Structure of Sr11Os4O24. Z. Für Naturforschung B 1998, 53, 31–36. 10.1515/znb-1998-0108. DOI

Wakeshima M.; Hinatsu Y. Crystal structure and magnetic ordering of novel perovskite-related barium osmate Ba11Os4O24. Solid State Commun. 2005, 136, 499–503. 10.1016/j.ssc.2005.09.025. DOI

Gemmi M.; Lanza A. E. 3D electron diffraction techniques. Acta Crystallogr. Sect. B Struct. Sci. Cryst. Eng. Mater. 2019, 75, 495–504. 10.1107/S2052520619007510. PubMed DOI

Gemmi M.; Mugnaioli E.; Gorelik T. E.; Kolb U.; Palatinus L.; Boullay P.; Hovmöller S.; Abrahams J. P. 3D Electron Diffraction: The Nanocrystallography Revolution. ACS Cent. Sci. 2019, 5, 1315.10.1021/acscentsci.9b00394. PubMed DOI PMC

Brázda P.; Klementová M.; Krysiak Y.; Palatinus L. Accurate lattice parameters from 3D electron diffraction data. I. Optical distortions. IUCrJ. 2022, 9, 735–755. 10.1107/S2052252522007904. PubMed DOI PMC

Khouchen M.; Klar P. B.; Chintakindi H.; Suresh A.; Palatinus L. Optimal estimated standard uncertainties of reflection intensities for kinematical refinement from 3D electron diffraction data. Acta Crystallogr. Sect. Found. Adv. 2023, 79, 427–439. 10.1107/S2053273323005053. PubMed DOI PMC

Klar P. B.; Krysiak Y.; Xu H.; Steciuk G.; Cho J.; Zou X.; Palatinus L. Accurate structure models and absolute configuration determination using dynamical effects in continuous-rotation 3D electron diffraction data. Nat. Chem. 2023, 15, 848–855. 10.1038/s41557-023-01186-1. PubMed DOI PMC

Palatinus L.; Petříček V.; Corrêa C. A. Structure refinement using precession electron diffraction tomography and dynamical diffraction: theory and implementation. Acta Crystallogr. Sect. Found. Adv. 2015, 71, 235–244. 10.1107/S2053273315001266. PubMed DOI

Palatinus L.; Corrêa C. A.; Steciuk G.; Jacob D.; Roussel P.; Boullay P.; Klementová M.; Gemmi M.; Kopeček J.; Domeneghetti M. C.; Cámara F.; Petříček V. Structure refinement using precession electron diffraction tomography and dynamical diffraction: tests on experimental data. Acta Crystallogr. Sect. B Struct. Sci. Cryst. Eng. Mater. 2015, 71, 740–751. 10.1107/S2052520615017023. PubMed DOI

Palatinus L.; Chapuis G. SUPERFLIP – a computer program for the solution of crystal structures by charge flipping in arbitrary dimensions. J. Appl. Crystallogr. 2007, 40, 786–790. 10.1107/S0021889807029238. DOI

Palatinus L. The charge-flipping algorithm in crystallography. Acta Crystallogr. Sect. B 2013, 69, 1–16. 10.1107/S2052519212051366. PubMed DOI

Petříček V.; Palatinus L.; Plášil J.; Dušek M. Jana2020 – a new version of the crystallographic computing system Jana. Z. Für Krist. - Cryst. Mater. 2023, 238, 271–282. 10.1515/zkri-2023-0005. DOI

Williams W. G.; Ibberson R. M.; Day P.; Enderby J. E. GEM — General materials diffractometer at ISIS. Phys. B Condens. Matter 1997, 241–243, 234–236. 10.1016/S0921-4526(97)00561-9. DOI

Coelho A. A. TOPAS and TOPAS-Academic: an optimization program integrating computer algebra and crystallographic objects written in C++. J. Appl. Crystallogr. 2018, 51, 210–218. 10.1107/S1600576718000183. DOI

Palatinus L.; Brázda P.; Jelínek M.; Hrdá J.; Steciuk G.; Klementová M. Specifics of the data processing of precession electron diffraction tomography data and their implementation in the program PETS2.0. Acta Crystallogr. Sect. B Struct. Sci. Cryst. Eng. Mater. 2019, 75, 512–522. 10.1107/S2052520619007534. PubMed DOI

Shannon R. D. Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr. A 1976, 32, 751–767. 10.1107/S0567739476001551. DOI