Phase relations in the CaOIrO2Ir system in air

McDaniel, C.L.; Schneider, Samuel J

doi:10.1016/0022-4596(72)90117-x

Cited by 67 publications

(22 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…the layered pPv structure with space group Cmcm and the GdFeO 3 -type Pv structure with space group Pbnm. These two compounds have been known since 1960s [22,23] and received significant attention from geologists since 2004 as an analogy of MgSiO 3 , the main constituent mineral of the Earth's lower mantle [16,24]. More recently, they have emerged as important correlated 5d-electron systems with strong SOC [14,25]; the strong local distortion in pPv CaIrO 3 makes it a model system to investigate the interplay of non-cubic crystal field splitting and SOC [15], while the orthorhombic Pv CaIrO 3 might be considered as an intriguing semimetal with symmetry-protected Dirac points [26].…”

Section: Cairomentioning

confidence: 99%

See 1 more Smart Citation

Synthesis, Crystal Structure, and Physical Properties of the Perovskite Iridates

Cai¹,

Li²,

Cheng³

2016

Perovskite Materials - Synthesis, Characterisation, Properties, and Applications

View full text Add to dashboard Cite

Perovskite iridates have emerged as a new paradigm for studying the strongly correlated electron physics with strong spin-orbit coupling. The "113" alkaline-earth iridates AIrO 3 (A = Ca, Sr, Ba) display a rich variety of crystallographic and electronic states and are now attracting growing research interest. This chapter aims to provide an overview for these "113" iridates, including the materials' synthesis, crystal structure, major physical properties, and other interesting results such as the effects of pressure and chemical substitutions, as well as theoretical perspectives.

show abstract

Section: Cairomentioning

confidence: 99%

“…In the earlier studies [12,22], it was reported that single-phase pPv phase cannot be obtained at ambient pressure through a solid-state reaction from CaCO 3 and IrO 2 in air.…”

Section: Synthesismentioning

confidence: 99%

Synthesis, Crystal Structure, and Physical Properties of the Perovskite Iridates

Cai¹,

Li²,

Cheng³

2016

Perovskite Materials - Synthesis, Characterisation, Properties, and Applications

View full text Add to dashboard Cite

show abstract

“…Calcium occupies bi-capped trigonal prism sites between these layers. Since the structure of CaIrO 3 was discovered and characterized, the material has been the subject of relatively few studies, though previous investigations find a phase transition to the perovskite (Pbnm) structure-type at high temperature (Hirose and Fujita 2005;McDaniel and Schneider 1972). Several studies have investigated the room-pressure CaO-IrO 2 phase diagram in air, finding CaIrO 3 stable to ~1020 °C (McDaniel and Schneider 1972;Rodi and Babel 1965).…”

Section: Introductionmentioning

confidence: 98%

“…Since the structure of CaIrO 3 was discovered and characterized, the material has been the subject of relatively few studies, though previous investigations find a phase transition to the perovskite (Pbnm) structure-type at high temperature (Hirose and Fujita 2005;McDaniel and Schneider 1972). Several studies have investigated the room-pressure CaO-IrO 2 phase diagram in air, finding CaIrO 3 stable to ~1020 °C (McDaniel and Schneider 1972;Rodi and Babel 1965). However, recent work (Martin et al 2007a) challenges these reports, concluding CaIrO 3 is metastable at 1 bar in air and only temporarily synthesized at room pressure when a (CaO + IrO 2 ) mixture is fired.…”

Section: Introductionmentioning

confidence: 99%

High-pressure structure and bonding in CaIrO3: The structure model of MgSiO3 post-perovskite investigated with time-of-flight neutron powder diffraction

Martin

Smith

Marshall

et al. 2007

American Mineralogist

View full text Add to dashboard Cite

The structure of CaIrO 3 (Cmcm) has been refined at high pressure and at low temperature using time-of-flight neutron powder diffraction data. Evidence supporting deviation from space group Cmcm to Cmc2 1 is inconclusive. As CaIrO 3 (Cmcm) unit-cell volume changes, refinements indicate deformation of cation-centered coordination polyhedra, rather than tilting. Structure models demonstrate Ca 2+ -centered polyhedra are an order of magnitude more compressible than Ir 4+ -centered octahedra. Bond valence sums show significant chemical strain (over-bonding) of calcium and oxygen at ambient conditions. Implications for structure change in MgSiO 3 post-perovskite are discussed and a method for predicting the Clapeyron slope between perovskite and post-perovskite phases is proposed based on extrapolation of the volume-ratio between cation-centered polyhedra.

show abstract

“…McDaniel et al have reported two polymorphisms of perovskitetype and post-perovskite-type CaIrO3. The perovskite CaIrO3 (pv-CaIrO3) is a metastable phase which can be prepared by solid state reaction in air 1) between 1173 and 1273 K, accompanying with a stable phase of post-perovskite CaIrO3 (ppv-CaIrO3). The space group of ppv-CaIrO3 is Cmcm and its lattice parameters are a = 0.31445, b = 0.98656 and c = 0.72986 nm.…”

Section: Introductionmentioning

confidence: 99%