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At least 1,459 records · Page 81
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ce2Si5Ir3 by Materials Project

Ce2Ir3Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Ce3+ is bonded in a 10-coordinate geometry to ten Si4- atoms. There are a spread of Ce–Si bond distances ranging from 3.00–3.27 Å. There are two inequivalent Ir+4.67+ sites. In the first Ir+4.67+ site, Ir+4.67+ is bonded in a distorted hexagonal planar geometry to six Si4- atoms. There are four shorter (2.46 Å) and two longer (2.62 Å) Ir–Si bond lengths. In the second Ir+4.67+ site, Ir+4.67+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Ir–Si bond distances ranging from 2.36–2.46 Å. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 8-coordinate geometry to four equivalent Ce3+ and four equivalent Ir+4.67+ atoms. In the second Si4- site, Si4- is bonded in a 2-coordinate geometry to four equivalent Ce3+, three Ir+4.67+, and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.54 Å. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Ce3+, three Ir+4.67+, and two equivalent Si4- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErSnIr by Materials Project

ErIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Er is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are four shorter (3.00 Å) and one longer (3.05 Å) Er–Ir bond lengths. There are two shorter (3.17 Å) and four longer (3.31 Å) Er–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Er and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.76 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Er and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.81 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Er and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThAlIr by Materials Project

ThIrAl crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Th is bonded in a 5-coordinate geometry to five Ir atoms. There are four shorter (3.01 Å) and one longer (3.02 Å) Th–Ir bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Th and six equivalent Al atoms. All Ir–Al bond lengths are 2.66 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Th and three equivalent Al atoms. All Ir–Al bond lengths are 2.86 Å. Al is bonded in a 4-coordinate geometry to four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tb2Si5Ir3 by Materials Project

Tb2Ir3Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Tb3+ is bonded in a 10-coordinate geometry to ten Si4- atoms. There are a spread of Tb–Si bond distances ranging from 2.95–3.26 Å. There are two inequivalent Ir+4.67+ sites. In the first Ir+4.67+ site, Ir+4.67+ is bonded in a distorted hexagonal planar geometry to six Si4- atoms. There are four shorter (2.46 Å) and two longer (2.59 Å) Ir–Si bond lengths. In the second Ir+4.67+ site, Ir+4.67+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Ir–Si bond distances ranging from 2.34–2.45 Å. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Tb3+, three Ir+4.67+, and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.54 Å. In the second Si4- site, Si4- is bonded in a 2-coordinate geometry to four equivalent Tb3+, three Ir+4.67+, and two equivalent Si4- atoms. In the third Si4- site, Si4- is bonded in a 8-coordinate geometry to four equivalent Tb3+ and four equivalent Ir+4.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho4Ge6Ir7 by Materials Project

Ho4Ir7Ge6 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Ho is bonded to six equivalent Ir and six equivalent Ge atoms to form HoGe6Ir6 cuboctahedra that share corners with twelve equivalent HoGe6Ir6 cuboctahedra, faces with six equivalent HoGe6Ir6 cuboctahedra, and faces with two equivalent IrGe6 octahedra. All Ho–Ir bond lengths are 2.97 Å. All Ho–Ge bond lengths are 3.02 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded to six equivalent Ge atoms to form IrGe6 octahedra that share faces with eight equivalent HoGe6Ir6 cuboctahedra. All Ir–Ge bond lengths are 2.67 Å. In the second Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Ho and four equivalent Ge atoms. All Ir–Ge bond lengths are 2.60 Å. Ge is bonded in a 9-coordinate geometry to four equivalent Ho and five Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YbSnIr by Materials Project

YbIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Yb is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are one shorter (2.98 Å) and four longer (3.05 Å) Yb–Ir bond lengths. There are two shorter (3.21 Å) and four longer (3.34 Å) Yb–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Yb and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.82 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Yb and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.75 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Yb and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sc4Si6Ir7 by Materials Project

Sc4Ir7Si6 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Sc is bonded to six equivalent Ir and six equivalent Si atoms to form ScSi6Ir6 cuboctahedra that share corners with twelve equivalent ScSi6Ir6 cuboctahedra, faces with six equivalent ScSi6Ir6 cuboctahedra, and faces with two equivalent IrSi6 octahedra. All Sc–Ir bond lengths are 2.85 Å. All Sc–Si bond lengths are 2.91 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded to six equivalent Si atoms to form IrSi6 octahedra that share faces with eight equivalent ScSi6Ir6 cuboctahedra. All Ir–Si bond lengths are 2.56 Å. In the second Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Sc and four equivalent Si atoms. All Ir–Si bond lengths are 2.50 Å. Si is bonded in a 9-coordinate geometry to four equivalent Sc and five Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LuSnIr by Materials Project

LuIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Lu is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are four shorter (2.98 Å) and one longer (3.03 Å) Lu–Ir bond lengths. There are two shorter (3.14 Å) and four longer (3.27 Å) Lu–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Lu and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.75 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Lu and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.80 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Lu and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrSi2Ir3 by Materials Project

PrIr3Si2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to two equivalent Pr, twelve Ir, and six equivalent Si atoms. Both Pr–Pr bond lengths are 3.65 Å. There are a spread of Pr–Ir bond distances ranging from 3.18–3.56 Å. There are a spread of Pr–Si bond distances ranging from 3.19–3.38 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Pr and four equivalent Si atoms. All Ir–Si bond lengths are 2.49 Å. In the second Ir site, Ir is bonded in a 4-coordinate geometry to four equivalent Pr and four equivalent Si atoms. There are two shorter (2.45 Å) and two longer (2.46 Å) Ir–Si bond lengths. Si is bonded in a 10-coordinate geometry to three equivalent Pr and six Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmSnIr by Materials Project

SmIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Sm is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are one shorter (3.05 Å) and four longer (3.07 Å) Sm–Ir bond lengths. There are two shorter (3.27 Å) and four longer (3.37 Å) Sm–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Sm and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.80 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Sm and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.84 Å. Sn is bonded in a 12-coordinate geometry to six equivalent Sm and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2Si5Ir3 by Materials Project

Y2Ir3Si5 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Y3+ is bonded in a 10-coordinate geometry to ten Si4- atoms. There are a spread of Y–Si bond distances ranging from 2.95–3.26 Å. There are two inequivalent Ir+4.67+ sites. In the first Ir+4.67+ site, Ir+4.67+ is bonded in a distorted hexagonal planar geometry to six Si4- atoms. There are four shorter (2.46 Å) and two longer (2.59 Å) Ir–Si bond lengths. In the second Ir+4.67+ site, Ir+4.67+ is bonded in a 5-coordinate geometry to five Si4- atoms. There are a spread of Ir–Si bond distances ranging from 2.34–2.45 Å. There are three inequivalent Si4- sites. In the first Si4- site, Si4- is bonded in a 4-coordinate geometry to four equivalent Y3+ and four equivalent Ir+4.67+ atoms. In the second Si4- site, Si4- is bonded in a 2-coordinate geometry to four equivalent Y3+, three Ir+4.67+, and two equivalent Si4- atoms. Both Si–Si bond lengths are 2.53 Å. In the third Si4- site, Si4- is bonded in a 9-coordinate geometry to four equivalent Y3+, three Ir+4.67+, and two equivalent Si4- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TmSnIr by Materials Project

TmIrSn crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Tm is bonded in a 11-coordinate geometry to five Ir and six equivalent Sn atoms. There are four shorter (2.99 Å) and one longer (3.03 Å) Tm–Ir bond lengths. There are two shorter (3.16 Å) and four longer (3.28 Å) Tm–Sn bond lengths. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 9-coordinate geometry to three equivalent Tm and six equivalent Sn atoms. All Ir–Sn bond lengths are 2.76 Å. In the second Ir site, Ir is bonded in a 9-coordinate geometry to six equivalent Tm and three equivalent Sn atoms. All Ir–Sn bond lengths are 2.81 Å. Sn is bonded in a 10-coordinate geometry to six equivalent Tm and four Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NdSi2Ir3 by Materials Project

NdIr3Si2 crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Nd is bonded in a 12-coordinate geometry to two equivalent Nd, twelve Ir, and six equivalent Si atoms. Both Nd–Nd bond lengths are 3.65 Å. There are a spread of Nd–Ir bond distances ranging from 3.18–3.55 Å. There are a spread of Nd–Si bond distances ranging from 3.18–3.37 Å. There are two inequivalent Ir sites. In the first Ir site, Ir is bonded in a 12-coordinate geometry to four equivalent Nd and four equivalent Si atoms. All Ir–Si bond lengths are 2.48 Å. In the second Ir site, Ir is bonded in a 4-coordinate geometry to four equivalent Nd and four equivalent Si atoms. There are two shorter (2.44 Å) and two longer (2.46 Å) Ir–Si bond lengths. Si is bonded in a 10-coordinate geometry to three equivalent Nd and six Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on B5Ir3W2 by Materials Project

W2Ir3B5 crystallizes in the orthorhombic Imm2 space group. The structure is three-dimensional. W2+ is bonded in a 7-coordinate geometry to six B3- atoms. There are a spread of W–B bond distances ranging from 2.22–2.31 Å. There are two inequivalent Ir+3.67+ sites. In the first Ir+3.67+ site, Ir+3.67+ is bonded in an L-shaped geometry to two equivalent B3- atoms. Both Ir–B bond lengths are 2.18 Å. In the second Ir+3.67+ site, Ir+3.67+ is bonded in a 4-coordinate geometry to four B3- atoms. There are one shorter (2.20 Å) and three longer (2.21 Å) Ir–B bond lengths. There are three inequivalent B3- sites. In the first B3- site, B3- is bonded in a 7-coordinate geometry to three equivalent W2+, one Ir+3.67+, and three equivalent B3- atoms. There is two shorter (1.77 Å) and one longer (1.89 Å) B–B bond length. In the second B3- site, B3- is bonded in a 7-coordinate geometry to three equivalent W2+, one Ir+3.67+, and three equivalent B3- atoms. In the third B3- site, B3- is bonded in a 6-coordinate geometry to six Ir+3.67+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Reversible CO 2 Hydrogenation, Neutron Crystallography, and Hydride Reactivity of a Triiridium Heptahydride Complex

Abstract The authors report the structure, reactivity, and catalytic utility of a triiridium complex, [Ir 3 H 6 ( μ 3 ‐H)(PN) 3 ] 2+ ( 2‐H , PN = (2‐pyridyl)CH 2 PBu t 2 ). Despite its unusual stability to unsaturated organics, electrophiles, and even CF 3 SO 3 D, they find that complex 2‐H catalyzes hydrogenation of CO 2 to formate (TON Ir = 9600) and reverse formic acid dehydrogenation (TON Ir = 54 400). The hydrogenation operates via a reactive intermediate [Ir 3 H 4 ( μ ‐H) 4 (PN) 3 ] + ( 5 ). Neutron crystallography and DFT‐supported neutron vibrational spectroscopy of 2‐H reveal Ir─H bond lengths and elucidate the vibration modes within the Ir 3 H 7 core. Stoichiometric oxidation of 2‐H produces four classes of iridium complexes of varied nuclearity and hydride structure: tetra‐ and pentanuclear clusters [Ir 3 H 6 ( μ 3 ‐AuPPh 3 )(PN) 3 ] 2+ ( 2‐Au ) and [Ag{Ir 2 H 4 ( μ ‐OAc)(PN) 2 } 2 ] 3+ ( 6 ) are generated using AuPPh 3 + and AgOAc, respectively. Further oxidation to class [Ir 2 H 3 ( μ ‐X) 2 (PN) 2 ] + is possible with AgOAc, Hg(OAc) 2 , or I 2 . Finally, a TEMPO/HCl system completely oxidizes the hydrides and gives [Ir 2 Cl 4 ( μ ‐Cl) 2 (PN) 2 ] ( 11 ).

Cherepakhin, Valeriy [Loker Hydrocarbon Research I↗
DOE OSTI2025

Reversible CO 2 Hydrogenation, Neutron Crystallography, and Hydride Reactivity of a Triiridium Heptahydride Complex

Here, the authors report the structure, reactivity, and catalytic utility of a triiridium complex, [Ir 3 H 6 (μ 3 -H)(PN) 3 ] 2+ (2-H, PN = (2-pyridyl)CH 2 PBu t 2 ). Despite its unusual stability to unsaturated organics, electrophiles, and even CF 3 SO 3 D, they find that complex 2-H catalyzes hydrogenation of CO 2 to formate (TON Ir = 9600) and reverse formic acid dehydrogenation (TON Ir = 54 400). The hydrogenation operates via a reactive intermediate [Ir 3 H 4 (μ-H) 4 (PN) 3 ] + (5). Neutron crystallography and DFT-supported neutron vibrational spectroscopy of 2-H reveal Ir─H bond lengths and elucidate the vibration modes within the Ir 3 H 7 core. Stoichiometric oxidation of 2-H produces four classes of iridium complexes of varied nuclearity and hydride structure: tetra- and pentanuclear clusters [Ir 3 H 6 (μ 3 -AuPPh 3 )(PN) 3 ] 2+ (2-Au) and [Ag{Ir 2 H 4 (μ-OAc)(PN) 2 } 2 ] 3+ (6) are generated using AuPPh 3 + and AgOAc, respectively. Further oxidation to class [Ir 2 H 3 (μ-X) 2 (PN) 2 ] + is possible with AgOAc, Hg(OAc) 2 , or I 2 . Finally, a TEMPO/HCl system completely oxidizes the hydrides and gives [Ir 2 Cl 4 (μ-Cl) 2 (PN) 2 ] (11).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Iridium-cobalt oxide synthesized via surfactant-assisted Adams fusion for efficient oxygen evolution in acidic and alkaline media

A series of iridium-cobalt (Ir-Co) oxide catalysts were synthesized using a modified surfactant-assisted Adams fusion method and evaluated for the oxygen evolution reaction (OER) in both acidic and alkaline media. The effect of varying the Ir/Co ratio was systematically studied and compared with commercial Ir black and pure IrO 2 samples. The actual elemental ratios were quantified using X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and inductively coupled plasma-mass spectrometry (ICP-MS). Among the synthesized samples, the Ir 6 Co 4 catalyst exhibited the best performance in acidic media, achieving an iR-corrected overpotential of 292 mV. In alkaline conditions, it demonstrated comparable activity to Ir black, with an iR-corrected overpotential of 263 mV. XPS and electron energy loss spectroscopy analyses revealed that increasing Co content led to a higher fraction of metallic Ir (Ir 0 ) in the catalyst. In addition, the role of Ir 3+ in enhancing OER activity was explored. A strong correlation was observed between higher Ir 3+ content and improved OER performance in acidic conditions.

Adams fusion↗
DOE OSTI2021

Ubiquitin-specific protease 14 promotes radio-resistance and suppresses autophagy in oral squamous cell carcinoma

Highlights: • USP14 promotes radioresistance of OSCC cells. • USP14 elevates radioresistance of OSCC cells by suppressing apoptosis. • USP14 modulates radioresistance in OSCC by regulating autophagy. Oral squamous cell carcinoma (OSCC) is a common malignant tumor in the world. Radiotherapy is one of the standard therapies for patients with OSCC, but its clinical efficiency is limited due to radioresistance. In this study, we identified a mechanism of such resistance regulated by Ubiquitin-specific protease 14 (USP14). USP14 expression was significantly increased in clinical OSCC tissue samples and cell lines, and OSCC patients with high USP14 expression predicted poor overall survival rate. Additionally, a negative correlation between USP14 and LC3B was observed in patients with OSCC. We then found that irradiation (IR)-reduced cell survival of OSCC cells lines was further decreased when USP14 was knocked down. However, USP14 over-expression significantly promoted the cell viability of OSCC cells after IR treatment. Colony formation analysis confirmed thatafter IR treatment,USP14 knockdown markedly decreased the proliferation of OSCC cells, but over-expressing USP14 significantly up-regulated the proliferative activity of OSCC cells. Furthermore, DNA damage caused by IR was enhanced by USP14 knockdown, while been suppressed in OSCC cells with USP14 over-expression. Additionally, IR-inducedapoptosis was further promoted by USP14 knockdown in OSCC cells, which was, however, significantly abolished by USP14 over-expression.Moreover, our in vivo studies showed that IR-reduced tumor growth and tumor weight were further enhanced by USP14 knockdown in OSCC tumor-bearing nude mice. Finally, we found that USP14 knockdown could promote IR-induced autophagy by increasing LC3BII and γH2AX expression levels in IR-treated OSCC cells. However, this event was markedly abolished by ATG5 knockdown, subsequently restoring the cell proliferation in IR-incubated OSCC cells.Finally, we found that USP14-mediated apoptosis was autophagy-dependent in IR-treated OSCC cells. Taken together, these findings suggested that suppressing USP14 could alleviateradioresistancein OSCC both in vitro and in vivo by inducing apoptosis and autophagy, and thus could be served as a promising therapeutic strategy for OSCC treatment.

60 APPLIED LIFE SCIENCES↗