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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 crystallizes in the monoclinic Cc space group. The structure is two-dimensional and consists of two V2O3 sheets oriented in the (0, 0, 1) direction. there are two inequivalent V3+ sites. In the first V3+ site, V3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of V–O bond distances ranging from 1.79–1.87 Å. In the second V3+ site, V3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of V–O bond distances ranging from 1.77–1.85 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two V3+ atoms. In the second O2- site, O2- is bonded in a linear geometry to two V3+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two V3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 is Corundum structured and crystallizes in the trigonal R-3c space group. The structure is three-dimensional. V3+ is bonded to six equivalent O2- atoms to form a mixture of corner, edge, and face-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 47–60°. There are three shorter (2.02 Å) and three longer (2.11 Å) V–O bond lengths. O2- is bonded to four equivalent V3+ atoms to form a mixture of distorted corner and edge-sharing OV4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 is Corundum structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to six O2- atoms to form a mixture of corner, edge, and face-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 46–61°. There are a spread of V–O bond distances ranging from 1.99–2.14 Å. In the second V3+ site, V3+ is bonded to six O2- atoms to form a mixture of corner, edge, and face-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 46–61°. There are a spread of V–O bond distances ranging from 1.98–2.15 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four V3+ atoms to form a mixture of distorted corner and edge-sharing OV4 trigonal pyramids. In the second O2- site, O2- is bonded to four V3+ atoms to form a mixture of distorted corner and edge-sharing OV4 trigonal pyramids. In the third O2- site, O2- is bonded to four V3+ atoms to form a mixture of distorted corner and edge-sharing OV4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are six inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to seven O2- atoms to form distorted VO7 pentagonal bipyramids that share corners with two VO6 octahedra, edges with two equivalent VO6 octahedra, and edges with four equivalent VO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 34–40°. There are a spread of V–O bond distances ranging from 2.05–2.24 Å. In the second V3+ site, V3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of V–O bond distances ranging from 2.00–2.44 Å. In the third V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra, a cornercorner with one VO7 pentagonal bipyramid, edges with three VO6 octahedra, and edges with two equivalent VO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 15–63°. There are a spread of V–O bond distances ranging from 2.00–2.18 Å. In the fourth V3+ site, V3+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra, a cornercorner with one VO7 pentagonal bipyramid, and edges with three VO6 octahedra. The corner-sharing octahedra tilt angles range from 15–61°. There are a spread of V–O bond distances ranging from 2.02–2.19 Å. In the fifth V3+ site, V3+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 61–63°. There are a spread of V–O bond distances ranging from 2.00–2.15 Å. In the sixth V3+ site, V3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of V–O bond distances ranging from 2.01–2.36 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to five V3+ atoms. In the second O2- site, O2- is bonded to four V3+ atoms to form distorted OV4 tetrahedra that share corners with two equivalent OV5 square pyramids, corners with three OV4 tetrahedra, and corners with six OV4 trigonal pyramids. In the third O2- site, O2- is bonded to four V3+ atoms to form distorted OV4 trigonal pyramids that share corners with two equivalent OV5 square pyramids, corners with three equivalent OV4 tetrahedra, corners with three OV4 trigonal pyramids, and edges with four OV4 trigonal pyramids. In the fourth O2- site, O2- is bonded to four V3+ atoms to form OV4 trigonal pyramids that share corners with two equivalent OV5 square pyramids, corners with three equivalent OV4 tetrahedra, corners with three OV4 trigonal pyramids, an edgeedge with one OV5 square pyramid, and edges with two equivalent OV4 trigonal pyramids. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to four V3+ atoms. In the sixth O2- site, O2- is bonded to five V3+ atoms to form OV5 square pyramids that share corners with three OV4 tetrahedra, corners with five OV4 trigonal pyramids, edges with two equivalent OV5 square pyramids, edges with two equivalent OV4 tetrahedra, and an edgeedge with one OV4 trigonal pyramid. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to five V3+ atoms. In the eighth O2- site, O2- is bonded to four V3+ atoms to form OV4 tetrahedra that share a cornercorner with one OV5 square pyramid, corners with three OV4 tetrahedra, corners with three equivalent OV4 trigonal pyramids, edges with two equivalent OV5 square pyramids, and edges with two equivalent OV4 tetrahedra. In the ninth O2- site, O2- is bonded to four V3+ atoms to form OV4 trigonal pyramids that share a cornercorner with one OV5 square pyramid, corners with three equivalent OV4 tetrahedra, corners with two equivalent OV4 trigonal pyramids, and edges with two equivalent OV4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to five O2- atoms to form distorted VO5 trigonal bipyramids that share corners with three equivalent VO6 octahedra, corners with four equivalent VO5 trigonal bipyramids, and edges with three equivalent VO6 octahedra. The corner-sharing octahedra tilt angles range from 48–78°. There are a spread of V–O bond distances ranging from 1.96–2.12 Å. In the second V3+ site, V3+ is bonded to six O2- atoms to form distorted VO6 octahedra that share corners with two equivalent VO6 octahedra, corners with three equivalent VO5 trigonal bipyramids, edges with three equivalent VO6 octahedra, and edges with three equivalent VO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There are a spread of V–O bond distances ranging from 1.96–2.18 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four V3+ atoms to form a mixture of distorted edge and corner-sharing OV4 trigonal pyramids. In the second O2- site, O2- is bonded in a trigonal planar geometry to three V3+ atoms. In the third O2- site, O2- is bonded to four V3+ atoms to form a mixture of distorted edge and corner-sharing OV4 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V2O3 by Materials Project

V2O3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent V3+ sites. In the first V3+ site, V3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 0–67°. There are a spread of V–O bond distances ranging from 1.97–2.17 Å. In the second V3+ site, V3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing VO6 octahedra. The corner-sharing octahedra tilt angles range from 54–67°. There are a spread of V–O bond distances ranging from 1.95–2.19 Å. In the third V3+ site, V3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of V–O bond distances ranging from 2.00–2.59 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three V3+ atoms. In the second O2- site, O2- is bonded to four V3+ atoms to form OV4 tetrahedra that share a cornercorner with one OV6 octahedra, corners with two equivalent OV4 tetrahedra, corners with three equivalent OV4 trigonal pyramids, edges with two equivalent OV6 octahedra, and edges with two equivalent OV4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. In the third O2- site, O2- is bonded in a 5-coordinate geometry to five V3+ atoms. In the fourth O2- site, O2- is bonded to four V3+ atoms to form OV4 trigonal pyramids that share a cornercorner with one OV6 octahedra, corners with three equivalent OV4 tetrahedra, corners with two equivalent OV4 trigonal pyramids, and edges with two equivalent OV4 trigonal pyramids. The corner-sharing octahedral tilt angles are 40°. In the fifth O2- site, O2- is bonded to six V3+ atoms to form distorted OV6 octahedra that share corners with two equivalent OV4 tetrahedra, corners with two equivalent OV4 trigonal pyramids, edges with two equivalent OV6 octahedra, and edges with four equivalent OV4 tetrahedra.

36 MATERIALS SCIENCE↗
NASA NTRS1984

Achondrite ALHA77005 - Alteration of chromite and olivine

The olivine crystals of the 77005 achondrite are brown except for colorless shock lamellae, mottled patches, and grains adjacent to pools of impact melt. Sporadic dark alteration patches in brown olivine and Cr-rich spinel gave the following average electron-microprobe analyses: (olivine) P2O5 0.9, SiO2 57.9, TiO2 0, Al2O3 0.7, Cr2O3 0.4, V2O3 0, Fe2O3 (assumed oxidation state) 17.0, MgO 1.6, CaO 0.2, Na2O 0, K2O 1.8, SO3 (assumed oxidation state) 9.2, Cl 0.1, sum 89.8 wt pct; (spinel) P2O5 3.5, SiO2 2.1, TiO2 2.2, Al2O3 2.1, Cr2O3 13.4, V2O3 0.8, Fe2O3 40.7, MgO 0.9, CaO 0.1, Na2O 0, K2O 2.0, SO3 11.1, Cl 0.1, sum 79.0 wt pct. Ion-microprobe analyses revealed H in both. Rare orange patches in brown olivine from another area gave SiO2 33-35, FeO 30-28, MgO 28-32, sum 93 wt pct. Thermal metamorphism under dry oxidizing conditions is discussed as a possible alternative to shock-induced oxidation for generation of the brown olivine (McSween and Stoeffler, 1980). Because alteration patches transgress shock lamellae, and because sulfatic alteration occurs in fusion crusts of Antarctic meteorites (Gibson et al., 1983), alteration of the 77005 achondrite at the Antarctic surface is preferred to a complex series of processes needed for preterrestrial alteration.

Smith, J. V.↗
NASA NTRS1986

Garnet melt viscosity, surface tension and drainage

Good surface morphology and layer uniformity of LPE-grown Bi YIG films are favored by fast melt removal after growth. Three flux modifying oxides: MoO3, V2O3, and WO3 are compared with respect to their effect on viscosity, surface tension and melt drainage. All three oxides increased the viscosities of Bi-garnet melts, but the viscosities and drainage times of V2O3 and MoO3 modified melts were smaller than those of WO3 modified melts. The liquid-gas surface tension was found to be temperature independent. The drainage process was strongly temperature dependent, 40 to 60 kcal/mol, whereas the viscosities of melts had activation energies of 11 to 16 kcal/mol. Contact angles of 16 + or - 2 deg were measured on frozen melt drops.

Luther, L. C.↗
DOE OSTI2020

Materials Data on V2Se2O11 by Materials Project

V2O3(SeO4)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. V5+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of V–O bond distances ranging from 1.60–2.38 Å. Se6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Se–O bond distances ranging from 1.64–1.70 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one V5+ and one Se6+ atom. In the second O2- site, O2- is bonded in a linear geometry to two equivalent V5+ atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one V5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one V5+ and one Se6+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one V5+ and one Se6+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one V5+ and one Se6+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS1972

Niobian rutile in an Apollo 14 KREEP fragment.

Niobian rutile was found in a KREEP lithic fragment of basaltic texture. The niobian rutile contains 85.3% TiO2, 7.1% Nb2O5, 2.65% Cr2O3, 0.70% ZrO2, 0.61% SiO2, 0.82% Al2O3 0.61% FeO, 0.52% CaO, 0.22% V2O3 in addition to minor amounts of MnO, MgO, and CeO2. Rare-earth elements were not detected, in contrast with lunar niobian rutile of Marvin (1971). Coexisting minerals in the KREEP fragment are major amounts of plagioclase and orthopyroxene, and minor amounts of olivine, ilmenite, augite, barian K-feldspar, whitlockite, troilite, Ni-Fe, zirkelite, and chromite.

Hlava, P. F.↗
NASA NTRS1990

Critical behavior in the hydrogen insulator-metal transition

The vibrational Raman spectrum of solid hydrogen has been measured from 77 to 295 K in the vicinity of the recently observed insulator-metal transition and low-temperature phase transition at 150 gigapascals. The measurements provide evidence for a critical point in the pressure-temperature phase boundary of the low-temperature transition. The result suggests that below the critical temperature the insulator-metal transition changes from continuous to discontinuous, consistent with the general criteria originally proposed by Mott (1949) for metallization by band-gap closure. The effect of temperature on hydrogen metallization closely resembles that of the lower-pressure insulator-metal transitions in doped V2O3 alloys.

Hemley, R. J.↗
NASA NTRS1995

Effect of Nb2O5 and V2O5 addition on the superconducting properties of YBa2Cu3O(y) thin films

The effect of Nb2O5 and V2O5 addition on the superconducting properties and microstructure of YBa2Cu3O(y) has been studied in thin films. Polycrystalline targets for laser ablation were prepared by mixing high purity V2O5 or Nb2O5 powders with a well characterized YBa2Cu3O(y) powder in the range 0 to 4 wt percent by solid state reaction method. Thin films (approximately 1500 A thickness) of the above targets were grown on (100) SrTiO3 (STO) and (100) LaAlO3 (LAO) substrates at 700 C temperature by pulsed laser deposition (PLD) technique. In the case of Nb2O5 addition we have noticed an increase in J(sub c) up to 0.5 wt percent and higher additive concentration (greater than 0.5 wt percent) have degraded the superconducting properties. However, in the case of V2O3 addition, there is an improvement in current density and microstructural properties up to 1 wt percent and the superconducting properties degrade for concentrations greater than 1 wt percent. The best J(sub c) for 0.5 wt percent of Nb2O5 added YBCO thin film is 1.6 x 10(exp 6) A/sq cm and for that of V2O5 added sample is 3.4 x 10(exp 6) A/sq cm at 77 K as compared to the pure YBa2Cu3O(y) (YBCO) film J(sub c) (1.2 x 10(exp 6) A/sq cm) observed on STO substrates. The reason for improvement in J(sub c) and microstructural properties in the case of V2O5 addition could be due to the low melting of V2O5 (690 C) which can act as a very good surfactant during deposition. Over all, we have realized that Nb2O5 addition or V2O5 addition to YBCO have shown significant improvement over the undoped YBa2Cu3O(7-x) films grown under identical conditions.

Srinivas, S.↗
NASA NTRSDate not supplied

Tin-Essako 001: A Metal-Rich Ureilite?

Introduction: Metal-rich achondrites include a variety of types, and likely have a variety of origins. Models range from gravitational mixing at the core-mantle boundaries of differentatiated asteroids, to complex impact mixing scenarios. We describe a new type of metal-rich achondrite that might be the first metal-rich ureilite. Sample: Tin-Essako (TE) 001 (~4.3 g) was found in Mali in 2020 and purchased by Jay Piatek in 2021. It was classified as a metal-rich ungrouped achondrite, with olivine and oxygen isotope (d18O=8.2810‰, d17O=3.718‰, avg. 3) compositions suggesting affinity to ureilites [1]. We studied one polished section (~187.7 mm2) of TE 001. Petrography: TE 001 consists of ~60% metal and 40% silicates, heterogeneously distributed. The metal is largely fresh, but iron oxides (presumably terrestrial) occur along one edge and in some patches and veins in the interior. The silicates are dominantly olivine (≥90%), with melt-textured areas of plagioclase + Si-rich glass. Minor phases include chromite and carbon. Olivine occurs as rounded grains (up to ~2.5 mm) in metal, commonly with rims of melt-textured plagioclase + glass. Olivine also occurs in more massive areas having a “honeycomb” texture, with rounded olivine “cells” surrounded by an interstitial network of reduced olivine riddled with tiny metal grains, plus melt-textured plagioclase + Si-rich glass. Chromite occurs as subhedral to rounded grains; smaller grains (30-250 mm) are included in olivine and a few larger grains (400-500 mm) are isolated within metal. A carbon phase occurs as lacy-textured rims around olivine grains in metal, or small patches within metal. Mineral Compositions: The olivine (excluding interstitial areas) is Fo 73.9±0.5, with 0.25±0.02 wt.% CaO, 0.31±0.01 wt% Cr2O3, 0.01 wt.% NiO, and molar Fe/Mn=49.8±2.2 (53 analyses). Olivine in interstitial areas has Fo up to at least 91. Smaller chromite grains have Fe# (molar Fe/[Fe+Mg]) = 0.54±0.01, Cr# (molar Cr/[Cr+Al]) = 0.52±0.01, 0.52±0.02 wt.% V2O3 and 0.21±0.04 wt% ZnO (28 analyses). One larger grain is zoned from Fe# = 0.45, Cr# =0.52 to Fe# = 0.40, Cr# =0.57, and contains thin Al-rich lamellae not resolved by EMPA. One irregularly shaped patch of chromite included in olivine has Fe# =0.26 and contains no ZnO. Plagioclase laths are An ~53-60, with ≤0.01 wt.% K2O. Glass contains 75-76 wt% SiO2 and ~16 wt% Al2O3. The metal contains 5.2±0.2 wt% Ni, 0.46±0.02 wt.% Co, and 0.01±0.01 wt.% Cr, with Si and P below detection (168 analyses). Discussion: The olivine + chromite assemblage in TE 001 is similar to the most ferroan ureilites (Fo ~75-79 [2]), as are the oxygen isotopes [1]. The presence of a carbon phase supports this, although the identity of this phase (graphite as in ureilites?) remains to be determined. The “honeycomb” textured areas, in particular, the presence of olivine “reduction rims,” resemble shock-smelted olivine areas in ureilites [3], but interstitial melt-textured plagioclase laths + glass like those in TE 001 have not been reported in such (or any) ureilites. Olivine in TE 001 is marginally more ferroan than in the most FeO-rich ureilite, with Fe-Mg-Mn composition offset from the trend of olivine + low-Ca pyroxene ureilites similar to augite-bearing ureilites [4]. CaO and Cr2O3 contents are in the range of those in ureilite olivine [ ] , though Cr2O3 is at the extreme low end of the range [5]. Chromites (except the unusual one) have similar Fe# to the most ferroan primary chromites in ureilites [2], but distinctly lower Cr# (0.52 vs. 0.71). Metal compositions are with the range for metal in ureilites [7]. The absence of pyroxene and sulfide, and the high abundance of metal in TE 001, are unlike ureilites. One possibility is that a ferroan, chromite-bearing, pyroxene-poor ureilite was invaded (possibly due to impact) by a metallic liquid (low S content suggests very high temperature), resulting in complete melting of pyroxene and smelting of olivine, with rapid recrystallization of melted silicate as plagioclase + glass. Alternatively, a pre-existing metal-rich ureilite assemblage may have been impact melted. Additional types of data will be obtained to evaluate these hypotheses (i.e., is the metal indigenous?) and assess affinity to ureilites.

olivine↗