Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Ag(NO)3”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Li3AgF4 by Materials Project

Li3AgF4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twenty-four inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.86–2.04 Å. In the second Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.83–1.88 Å. In the third Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.92–2.05 Å. In the fourth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.80–1.92 Å. In the fifth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.84–1.89 Å. In the sixth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of distorted edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.86–2.05 Å. In the seventh Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.85–1.91 Å. In the eighth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.87–2.04 Å. In the ninth Li1+ site, Li1+ is bonded in a distorted trigonal non-coplanar geometry to three F1- atoms. There are a spread of Li–F bond distances ranging from 1.88–1.90 Å. In the tenth Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.86–2.14 Å. In the eleventh Li1+ site, Li1+ is bonded to four F1- atoms to form distorted corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.86–1.98 Å. In the twelfth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.83–1.92 Å. In the thirteenth Li1+ site, Li1+ is bonded to four F1- atoms to form corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.89–2.26 Å. In the fourteenth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.86–2.03 Å. In the fifteenth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of distorted edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.87–2.00 Å. In the sixteenth Li1+ site, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four F1- atoms. There are a spread of Li–F bond distances ranging from 1.94–2.05 Å. In the seventeenth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.85–1.90 Å. In the eighteenth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.84–1.90 Å. In the nineteenth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.87–2.03 Å. In the twentieth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.84–1.89 Å. In the twenty-first Li1+ site, Li1+ is bonded to four F1- atoms to form distorted corner-sharing LiF4 tetrahedra. There are a spread of Li–F bond distances ranging from 1.84–1.97 Å. In the twenty-second Li1+ site, Li1+ is bonded to four F1- atoms to form distorted corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.87–2.32 Å. In the twenty-third Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.85–2.11 Å. In the twenty-fourth Li1+ site, Li1+ is bonded to four F1- atoms to form a mixture of distorted edge and corner-sharing LiF4 trigonal pyramids. There are a spread of Li–F bond distances ranging from 1.91–2.03 Å. There are eight inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.30–2.97 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.24–3.10 Å. In the third Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.30–2.89 Å. In the fourth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.34–2.74 Å. In the fifth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.30–2.86 Å. In the sixth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.36–2.72 Å. In the seventh Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.26–2.85 Å. In the eighth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to six F1- atoms. There are a spread of Ag–F bond distances ranging from 2.30–2.87 Å. There are thirty-two inequivalent F1- sites. In the first F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted FLi3Ag tetrahedra that share corners with two FLi3Ag tetrahedra and a cornercorner with one FLi2Ag2 trigonal pyramid. In the second F1- site, F1- is bonded in a 5-coordinate geometry to four Li1+ and one Ag1+ atom. In the third F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted corner-sharing FLi3Ag trigonal pyramids. In the fourth F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted corner-sharing FLi3Ag trigonal pyramids. In the fifth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and two Ag1+ atoms. In the sixth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag1+ atom. In the seventh F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Ag1+ atom. In the eighth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag1+ atom. In the ninth F1- site, F1- is bonded in a 2-coordinate geometry to two Li1+ and two Ag1+ atoms. In the tenth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and two Ag1+ atoms. In the eleventh F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted corner-sharing FLi3Ag tetrahedra. In the twelfth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the thirteenth F1- site, F1- is bonded in a 4-coordinate geometry to two Li1+ and two Ag1+ atoms. In the fourteenth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and two Ag1+ atoms. In the fifteenth F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted corner-sharing FLi3Ag tetrahedra. In the sixteenth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the seventeenth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the eighteenth F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag1+ atom. In the nineteenth F1- site, F1- is bonded in a 4-coordinate geometry to four Li1+ and one Ag1+ atom. In the twentieth F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and one Ag1+ atom. In the twenty-first F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag1+ atom. In the twenty-second F1- site, F1- is bonded in a 4-coordinate geometry to three Li1+ and two Ag1+ atoms. In the twenty-third F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted FLi3Ag tetrahedra that share a cornercorner with one FLi3Ag tetrahedra and a cornercorner with one FLi2Ag2 trigonal pyramid. In the twenty-fourth F1- site, F1- is bonded to three Li1+ and one Ag1+ atom to form distorted corner-sharing FLi3Ag tetrahedra. In the twenty-fifth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the twenty-sixth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the twenty-seventh F1- site, F1- is bonded in a 3-coordinate geometry to three Li1+ and one Ag1+ atom. In the twenty-eighth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the twenty-ninth F1- site, F1- is bonded to two Li1+ and two Ag1+ atoms to form distorted corner-sharing FLi2Ag2 trigonal pyramids. In the thirtieth F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the thirty-first F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms. In the thirty-second F1- site, F1- is bonded in a 5-coordinate geometry to three Li1+ and two Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Electrochemical Separation of Ag 2 S and Cu 2 S from Molten Sulfide Electrolyte

The production of precious metals from Cu-rich sources such as ore products or secondary sources is slow and complex largely due to limited solubility in aqueous electrolytes. This results in sequential processing with various electrolytes and chemistries, where first Cu is electrorefined, followed by Ag, followed by Au and the platinum group metals. These are separate processes, often conducted in separate electrorefining and electrowinning facilities. The chemical properties of molten sulfides, and their ability to operate at a temperature where liquid metal cathodes are used, suggest the possibility of an alternative, streamlined processing route for Cu and precious metals. Unfortunately, little thermodynamic or electrochemical information is available regarding the behavior of Cu and precious metal sulfides in molten sulfide electrolytes. Herein, the relative activity of the Cu 2 S-Ag 2 S pseudobinary dissolved in a BaS-La 2 S 3 supporting electrolyte is measured at 1523 K. It was found that the supporting electrolyte favors mixing with Ag 2 S over Cu 2 S. Molten sulfide electrolysis of Cu and Ag was conducted, with results in good agreement with the thermodynamic model. It is found that the Ag-Cu cathode chemistry will influence the electrochemical selectivity in the Ag-Cu-Ba-La-S system.

25 ENERGY STORAGE↗
DOE OSTI2020

Materials Data on AgBiS2 by Materials Project

AgBiS2 is Caswellsilverite-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded to six S2- atoms to form AgS6 octahedra that share corners with two equivalent BiS6 octahedra, corners with four equivalent AgS6 octahedra, edges with four equivalent AgS6 octahedra, and edges with eight BiS6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Ag–S bond distances ranging from 2.77–2.96 Å. In the second Ag1+ site, Ag1+ is bonded to six S2- atoms to form AgS6 octahedra that share corners with two equivalent BiS6 octahedra, corners with four equivalent AgS6 octahedra, edges with four equivalent AgS6 octahedra, and edges with eight BiS6 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. There are a spread of Ag–S bond distances ranging from 2.77–2.96 Å. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with two equivalent AgS6 octahedra, corners with four equivalent BiS6 octahedra, edges with four equivalent BiS6 octahedra, and edges with eight AgS6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Bi–S bond distances ranging from 2.73–2.89 Å. In the second Bi3+ site, Bi3+ is bonded to six S2- atoms to form BiS6 octahedra that share corners with two equivalent AgS6 octahedra, corners with four equivalent BiS6 octahedra, edges with four equivalent BiS6 octahedra, and edges with eight AgS6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Bi–S bond distances ranging from 2.75–2.86 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ag1+ and three Bi3+ atoms to form a mixture of edge and corner-sharing SAg3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 2–3°. In the second S2- site, S2- is bonded to three Ag1+ and three Bi3+ atoms to form a mixture of edge and corner-sharing SAg3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. In the third S2- site, S2- is bonded to three Ag1+ and three Bi3+ atoms to form a mixture of edge and corner-sharing SAg3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. In the fourth S2- site, S2- is bonded to three Ag1+ and three Bi3+ atoms to form a mixture of edge and corner-sharing SAg3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 2–3°.

36 MATERIALS SCIENCE↗
DOE OSTI2023

An Aerosol Jet Printed Resistance Temperature Detector‐Micro Hotplate with Temperature Coefficient of Resistance Stabilized by Electrical Sintering

Abstract Aerosol jet printing (AJP) is an emerging direct write tool enabling rapid prototyping and fabrication of electronics components. AJP provides faster and less expensive production of devices with feature sizes of >10 microns compared to traditional MEMS processes. Herein, the fabrication of a resistance temperature detector‐micro hotplate (RTD‐µHP) is reported using AJP printed silver. AJP eliminates sophisticated MEMS processes such as masking, alignment, and etching. The compatibility of the AJP process with a broad range of materials is demonstrated by printing highly resolved lines on rigid and flexible substrates. Optimal thermal sintering conditions of AJP printed silver (Ag) lines are found by in situ resistance measurements. To stabilize the temperature coefficient of resistance (TCR) of the RTD‐µHP at high operating current levels, electrical sintering is performed on the RTD‐µHPs. Electrical sintering improves the conductivity of fully thermally sintered Ag RTD‐µHPs by 32% and provides a burn‐in mechanism for stabilizing the TCR. The TCR of the RTD‐µHPs after electrical sintering is 3.80 × 10 −3 at 22 °C, close to the value for bulk Ag. The performance of the RTD‐µHPs is tested using a reference thermocouple. The RTD‐µHPs show reliable and repeatable heating and temperature sensing up to 70 °C in air.

Sui, Yongkun↗
DOE OSTI2020

Materials Data on Ag7AsS6 by Materials Project

Ag7AsS6 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four S2- atoms. There are a spread of Ag–S bond distances ranging from 2.54–2.84 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to four S2- atoms. There are a spread of Ag–S bond distances ranging from 2.53–3.23 Å. In the third Ag1+ site, Ag1+ is bonded in a linear geometry to two S2- atoms. There are one shorter (2.41 Å) and one longer (2.43 Å) Ag–S bond lengths. As5+ is bonded in a tetrahedral geometry to four S2- atoms. There are three shorter (2.21 Å) and one longer (2.23 Å) As–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to three Ag1+ and one As5+ atom to form distorted corner-sharing SAg3As tetrahedra. In the second S2- site, S2- is bonded in a 7-coordinate geometry to seven Ag1+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to seven Ag1+ atoms. In the fourth S2- site, S2- is bonded to three equivalent Ag1+ and one As5+ atom to form corner-sharing SAg3As tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag8SnSe6 by Materials Project

Ag8SnSe6 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are five inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.68–2.76 Å. In the second Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two Se2- atoms. There are one shorter (2.59 Å) and one longer (2.61 Å) Ag–Se bond lengths. In the third Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to four Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.57–3.66 Å. In the fourth Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.71–2.79 Å. In the fifth Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.69–2.94 Å. Sn4+ is bonded in a tetrahedral geometry to four Se2- atoms. There are a spread of Sn–Se bond distances ranging from 2.55–2.57 Å. There are five inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 5-coordinate geometry to five Ag1+ atoms. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to eight Ag1+ atoms. In the third Se2- site, Se2- is bonded in a distorted trigonal pyramidal geometry to three Ag1+ and one Sn4+ atom. In the fourth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Ag1+ and one Sn4+ atom. In the fifth Se2- site, Se2- is bonded in a 5-coordinate geometry to four Ag1+ and one Sn4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag2CO3 by Materials Project

Ag2CO3 crystallizes in the trigonal P31c space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Ag–O bond distances ranging from 2.32–2.84 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Ag–O bond distances ranging from 2.17–2.48 Å. There are three inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. In the third C4+ site, C4+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All C–O bond lengths are 1.30 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ag1+ and one C4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Ag1+ and one C4+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Ag1+ and one C4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag2S by Materials Project

Ag2S crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to two equivalent S2- atoms. Both Ag–S bond lengths are 2.47 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three equivalent S2- atoms. There are a spread of Ag–S bond distances ranging from 2.54–2.79 Å. S2- is bonded in a 5-coordinate geometry to five Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Code Standard Evaluation for ASME AG-1-2019, Section FL

ASME AG-1 Section FL Deep Bed Sand Filters includes a requirement to use Special Test Sections to provide a representative assessment of the filter efficiency. The SRPPF project design basis is to test the entire filter bed (versus a representative sample) following the same basis methodology to test the existing filters at the Savannah River Site. Using a combination of: 1) the filter testing experience at SRS since the early 1970’s, 2) the methodology found in ASME AG-1 for testing high capacity HEPA filter housings and 3) requirements for stack or duct sampling systems published by the Environmental Protection Agency (EPA), the Special Test Sections methodology for Deep Bed Sand (DBS) filters in ASME AG-1 Section FL has been replaced with a methodology to test the entire DBS filter system.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2010

Rocket-Plume Spectroscopy Simulation for Hydrocarbon-Fueled Rocket Engines

The UV-Vis spectroscopic system for plume diagnostics monitors rocket engine health by using several analytical tools developed at Stennis Space Center (SSC), including the rocket plume spectroscopy simulation code (RPSSC), to identify and quantify the alloys from the metallic elements observed in engine plumes. Because the hydrocarbon-fueled rocket engine is likely to contain C2, CO, CH, CN, and NO in addition to OH and H2O, the relevant electronic bands of these molecules in the spectral range of 300 to 850 nm in the RPSSC have been included. SSC incorporated several enhancements and modifications to the original line-by-line spectral simulation computer program implemented for plume spectral data analysis and quantification in 1994. These changes made the program applicable to the Space Shuttle Main Engine (SSME) and the Diagnostic Testbed Facility Thruster (DTFT) exhaust plume spectral data. Modifications included updating the molecular and spectral parameters for OH, adding spectral parameter input files optimized for the 10 elements of interest in the spectral range from 320 to 430 nm and linking the output to graphing and analysis packages. Additionally, the ability to handle the non-uniform wavelength interval at which the spectral computations are made was added. This allowed a precise superposition of wavelengths at which the spectral measurements have been made with the wavelengths at which the spectral computations are done by using the line-by-line (LBL) code. To account for hydrocarbon combustion products in the plume, which might interfere with detection and quantification of metallic elements in the spectral region of 300 to 850 nm, the spectroscopic code has been enhanced to include the carbon-based combustion species of C2, CO, and CH. In addition, CN and NO have spectral bands in 300 to 850 nm and, while these molecules are not direct products of hydrocarbon-oxygen combustion systems, they can show up if nitrogen or a nitrogen compound is present as an impurity in the propellants and/or these can form in the boundary layer as a result of interaction of the hot plume with the atmosphere during the ground testing of engines. Ten additional electronic band systems of these five molecules have been included into the code. A comprehensive literature search was conducted to obtain the most accurate values for the molecular and the spectral parameters, including Franck-Cordon factors and electronic transition moments for all ten band systems. For each elemental transition in the RPSSC, six spectral parameters - Doppler broadened line width at half-height, pressure-broadened line width at half-height, electronic multiplicity of the upper state, electronic term energy of the upper state, Einstein transition probability coefficient, and the atomic line center - are required. Input files have been created for ten elements of Ni, Fe, Cr, Co, Cu, Ca, Mn, Al, Ag, and Pd, which retain only relatively moderate to strong transitions in 300 to 430 nm spectral range for each element. The number of transitions in the input files is 68 for Ni; 148 for Fe; 6 for Cr; 87 for Co; 1 for Ca; 3 for Mn; 2 each for Cu, Al, and Ag; and 11 for Pd.

Tejwani, Gopal D.↗
DOE OSTI2022

Acetate formation on metals via CH 4 carboxylation by CO 2 : A DFT study

Here, density functional theory calculations have been performed to investigate CH 4 activation and coupling to CO 2 forming C 2 carboxylates such as acetate on the close-packed (111) or (0001) surfaces of ten mid-to-late transition and coinage metals (Co, Ni, Cu, Ru, Rh, Pd, Ag, Ir, Pt, and Au). Consistent with the literature, the activation energy (E a ) for the initial C-H bond scission in CH 4 is mild, being ca. 1 eV or less on all but the coinage metals, of which Ag exhibits the highest E a at 2.13 eV, followed by Au and Cu. E a for the CH 3 -CO 2 coupling step is 0.8 ~ 1.1 eV on Co, Ru, Rh, and Ag, 1.2 ~ 1.5 eV on Ni, Cu, Pd, and Ir, and 1.8 ~ 2.1 eV on Pt and Au. While the two E a are comparable for several metals in terms of DFT total energies, free energy analysis indicates CH 3 -CO 2 coupling to be much more rate-limiting than CH 4 activation. Overcoming it would require over 800 K even on the most active of the metals considered, Ru, which makes the formation of acetate not feasible on the monometallic metal surfaces. Instead, we propose that single atom alloys based on early transition metals doped into a host metal such as Ni(111) could be viable catalysts. The dopant sites serve to stabilize the transition state of C-C coupling while Ni sites continue to activate CH 4 , thereby significantly lowering the required temperature for acetate formation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on AgIO4 by Materials Project

AgIO4 is Zircon-like structured and crystallizes in the tetragonal I4_1/a space group. The structure is three-dimensional. Ag3+ is bonded in a 8-coordinate geometry to eight equivalent O2- atoms. There are four shorter (2.59 Å) and four longer (2.62 Å) Ag–O bond lengths. O2- is bonded in a 3-coordinate geometry to two equivalent Ag3+ and one I5+ atom. The O–I bond length is 1.82 Å. I5+ is bonded in a tetrahedral geometry to four equivalent O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag8GeTe6 by Materials Project

Ag8GeTe6 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 2-coordinate geometry to four Ag1+ and two Te2- atoms. There are a spread of Ag–Ag bond distances ranging from 2.92–3.01 Å. There are one shorter (2.75 Å) and one longer (2.82 Å) Ag–Te bond lengths. In the second Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to one Ag1+ and four Te2- atoms. The Ag–Ag bond length is 2.94 Å. There are a spread of Ag–Te bond distances ranging from 2.94–3.01 Å. In the third Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to two Ag1+ and four Te2- atoms. There are one shorter (2.89 Å) and one longer (3.20 Å) Ag–Ag bond lengths. There are a spread of Ag–Te bond distances ranging from 2.76–3.41 Å. In the fourth Ag1+ site, Ag1+ is bonded in a 5-coordinate geometry to one Ag1+ and four Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.84–3.06 Å. In the fifth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two Ag1+ and four Te2- atoms. There are one shorter (2.77 Å) and one longer (2.85 Å) Ag–Ag bond lengths. There are a spread of Ag–Te bond distances ranging from 2.83–3.02 Å. In the sixth Ag1+ site, Ag1+ is bonded in a 9-coordinate geometry to four Ag1+ and five Te2- atoms. There are one shorter (2.82 Å) and one longer (2.89 Å) Ag–Ag bond lengths. There are a spread of Ag–Te bond distances ranging from 2.85–3.93 Å. In the seventh Ag1+ site, Ag1+ is bonded in a rectangular see-saw-like geometry to four Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.78–2.93 Å. In the eighth Ag1+ site, Ag1+ is bonded in a 7-coordinate geometry to three Ag1+ and four Te2- atoms. The Ag–Ag bond length is 2.97 Å. There are a spread of Ag–Te bond distances ranging from 2.78–3.08 Å. In the ninth Ag1+ site, Ag1+ is bonded in a 7-coordinate geometry to three Ag1+ and four Te2- atoms. The Ag–Ag bond length is 2.84 Å. There are a spread of Ag–Te bond distances ranging from 2.90–3.21 Å. In the tenth Ag1+ site, Ag1+ is bonded in a 8-coordinate geometry to four Ag1+ and four Te2- atoms. There are one shorter (2.88 Å) and one longer (3.14 Å) Ag–Ag bond lengths. There are a spread of Ag–Te bond distances ranging from 2.86–3.27 Å. In the eleventh Ag1+ site, Ag1+ is bonded in a 7-coordinate geometry to three Ag1+ and four Te2- atoms. There are one shorter (2.82 Å) and one longer (2.94 Å) Ag–Ag bond lengths. There are a spread of Ag–Te bond distances ranging from 2.84–3.22 Å. In the twelfth Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to one Ag1+ and four Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.86–3.08 Å. In the thirteenth Ag1+ site, Ag1+ is bonded in a 9-coordinate geometry to four Ag1+ and five Te2- atoms. The Ag–Ag bond length is 2.81 Å. There are a spread of Ag–Te bond distances ranging from 2.81–3.94 Å. In the fourteenth Ag1+ site, Ag1+ is bonded in a 7-coordinate geometry to three Ag1+ and four Te2- atoms. The Ag–Ag bond length is 2.80 Å. There are a spread of Ag–Te bond distances ranging from 2.84–3.05 Å. In the fifteenth Ag1+ site, Ag1+ is bonded in a 6-coordinate geometry to two Ag1+ and four Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.85–3.10 Å. In the sixteenth Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to one Ag1+ and three Te2- atoms. There are a spread of Ag–Te bond distances ranging from 2.79–2.97 Å. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four Te2- atoms. There are a spread of Ge–Te bond distances ranging from 2.53–2.66 Å. In the second Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four Te2- atoms. There are a spread of Ge–Te bond distances ranging from 2.58–2.63 Å. There are twelve inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 7-coordinate geometry to seven Ag1+ atoms. In the second Te2- site, Te2- is bonded in a 8-coordinate geometry to eight Ag1+ atoms. In the third Te2- site, Te2- is bonded in a 7-coordinate geometry to seven Ag1+ atoms. In the fourth Te2- site, Te2- is bonded in a distorted L-shaped geometry to one Ag1+ and one Ge4+ atom. In the fifth Te2- site, Te2- is bonded in a 5-coordinate geometry to five Ag1+ and one Ge4+ atom. In the sixth Te2- site, Te2- is bonded in a distorted hexagonal bipyramidal geometry to eight Ag1+ atoms. In the seventh Te2- site, Te2- is bonded in a 5-coordinate geometry to five Ag1+ and one Ge4+ atom. In the eighth Te2- site, Te2- is bonded in a 6-coordinate geometry to five Ag1+ and one Ge4+ atom. In the ninth Te2- site, Te2- is bonded in a 4-coordinate geometry to three Ag1+ and one Ge4+ atom. In the tenth Te2- site, Te2- is bonded in a 6-coordinate geometry to five Ag1+ and one Ge4+ atom. In the eleventh Te2- site, Te2- is bonded in a 5-coordinate geometry to four Ag1+ and one Ge4+ atom. In the twelfth Te2- site, Te2- is bonded in a 6-coordinate geometry to five Ag1+ and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Methane Activation on Metal-Doped (111) and (100) Ceria Surfaces with Charge-Compensating Oxygen Vacancies

Reducing the temperature for methane activation is an important objective that would benefit many technological applications. In this work we explore the possibility to achieve this goal using single atom catalysts (SACs) on ceria surfaces. In particular, we focus on Ag SACs, which have recently been suggested to be promising catalysts for both the oxidation of molecular hydrogen and CH 4 activation. The rate limiting step of methane activation on ceria is the breaking of the first C-H bond. Using first principles calculations, we investigate this reaction on CeO 2 (111) and (100) surfaces, which are both frequently exposed on ceria nanoparticles. For undoped ceria, our results show that the dissociation of CH 4 to CH 3 + H has a lower barrier on the (001) surface than on the (111) one. On both surfaces, the presence of Ag enhances the binding of CH 4 to the surface and reduces the activation energy for its dissociation. Interestingly, the formation of methanol via the Mars-van Krevelen mechanism has a slightly lower energy barrier than the dissociation of CH 4 to CH 3 + H on Ag-doped CeO 2 (111), suggesting that methanol is a likely product of methane activation on this surface. Here, a novel aspect of our work relative to previous studies on CH 4 activation over transition metal doped ceria is that we mainly focus on stable surface structures where each Ag dopant substituting a Ce atom forms a complex with a surface oxygen vacancy (VO). Our results show that these Ag-VO complexes play a critical role and accounting for their presence is essential for a proper description of the surface reactivity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Dual-atom Ag 2 /graphene catalyst for efficient electroreduction of CO 2 to CO

Electrochemical reduction of CO 2 into value-added carbon compounds offers a promising strategy to mitigate global warming, but present challenges for chemistry due to the poor selectivity and stability of electrocatalysts. In this work, we report a dual-atom Ag 2 /graphene catalyst featuring well-defined AgN 3 -AgN 3 active site for CO 2 electrochemical reduction. This dual-atom catalyst can drive CO 2 reduction reaction at a potential as high as -0.25 V, and exhibit excellent CO Faradic efficiency up to 93.4 % with a current density of 11.87 mA cm -2 at -0.7 V and long-term stability, far surpassing the single-atom Ag 1 /graphene and the traditional silver nanoparticle catalysts. Finally, DFT calculations reveal that the dual-atom Ag site lowers the barrier for the formation of *COOH by stabilizing the *CO 2 through the concomitant interactions with the C and an O atom of CO 2 , resulting in excellent catalytic performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on Al(Ag3Se2)3 by Materials Project

Al(Ag3Se2)3 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.74–3.18 Å. In the second Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three Se2- atoms. There are two shorter (2.62 Å) and one longer (2.77 Å) Ag–Se bond lengths. In the third Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to four Se2- atoms. There are a spread of Ag–Se bond distances ranging from 2.67–3.37 Å. Al3+ is bonded in a tetrahedral geometry to four Se2- atoms. There are one shorter (2.38 Å) and three longer (2.41 Å) Al–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to three equivalent Ag1+ and one Al3+ atom. In the second Se2- site, Se2- is bonded in a 6-coordinate geometry to six Ag1+ atoms. In the third Se2- site, Se2- is bonded in a 9-coordinate geometry to nine Ag1+ atoms. In the fourth Se2- site, Se2- is bonded in a 1-coordinate geometry to five Ag1+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2Ag4S3 by Materials Project

K2Ag4S3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six S2- atoms to form a mixture of distorted corner, edge, and face-sharing KS6 octahedra. The corner-sharing octahedra tilt angles range from 40–64°. There are a spread of K–S bond distances ranging from 3.35–3.39 Å. In the second K1+ site, K1+ is bonded to six S2- atoms to form a mixture of distorted corner, edge, and face-sharing KS6 octahedra. The corner-sharing octahedra tilt angles range from 40–64°. There are a spread of K–S bond distances ranging from 3.17–3.41 Å. There are four inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a distorted trigonal planar geometry to three S2- atoms. There are two shorter (2.57 Å) and one longer (2.63 Å) Ag–S bond lengths. In the second Ag1+ site, Ag1+ is bonded in a distorted trigonal planar geometry to three S2- atoms. There are two shorter (2.49 Å) and one longer (2.71 Å) Ag–S bond lengths. In the third Ag1+ site, Ag1+ is bonded in a distorted trigonal planar geometry to three S2- atoms. There are one shorter (2.55 Å) and two longer (2.73 Å) Ag–S bond lengths. In the fourth Ag1+ site, Ag1+ is bonded in a 3-coordinate geometry to three S2- atoms. There are one shorter (2.52 Å) and two longer (2.75 Å) Ag–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 9-coordinate geometry to three K1+ and six Ag1+ atoms. In the second S2- site, S2- is bonded in a 7-coordinate geometry to four K1+ and three Ag1+ atoms. In the third S2- site, S2- is bonded in a 8-coordinate geometry to five K1+ and three Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AgF2 by Materials Project

AgF2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Ag2+ is bonded to six equivalent F1- atoms to form a mixture of corner and edge-sharing AgF6 octahedra. The corner-sharing octahedra tilt angles range from 44–58°. There are a spread of Ag–F bond distances ranging from 2.12–2.62 Å. F1- is bonded in a 3-coordinate geometry to three equivalent Ag2+ atoms.

36 MATERIALS SCIENCE↗