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SAF Grand Challenge: October 2021 – September 2024 Progress Report Fact Sheet

An interagency team led by the U.S. Department of Energy (DOE), U.S. Department of Agriculture (USDA), U.S. Department of Transportation (DOT), and other federal agencies including the U.S. Department of Defense, U.S. Environmental Protection Agency, National Aeronautics and Space Administration, and Commercial Aviation Alternative Fuels Initiative have made important progress on accelerating acceptance and growth of sustainable aviation fuel (SAF) as a primary strategy in aviation decarbonization. The progress made by these federal agencies supports the interagency SAF Grand Challenge, including new funding opportunities and initiatives aligned with the SAF Grand Challenge Roadmap; providing expertise and technical assistance to industry; increasing interagency collaboration; and providing data, modeling, and analysis to decision makers.

Sustainable Aviation Fuel Aviation SAF↗

Fact Sheet - Long-length Scintillating Fibers for Radiation Detection

As the world looks to underground geological repositories for storing nuclear waste, technologies to safeguard the material are needed. An example of a project that developed a new technology is Tripwire. Tripwire proposes a multi-sensor system approach for geological spent nuclear fuel repositories that relies of radiation, vibration, and electromagnetic detection. Tripwire was developed by the Applied Radiation Measurements and Systems (ARMS) group at INL and sponsored by the National Nuclear Security Administration (NNSA). The ARMS group performs research and development, testing and evaluation, operational support, and training focused on applied ionizing radiation detection and measurement. Application areas include nuclear engineering for advanced reactors and fuel cycle operations, nuclear nonproliferation, nuclear counterproliferation, nuclear forensics, and arms control and disarmament.

46 - INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AN↗

HPC Info Sheet

A flyer with current HPC systems.

97 - MATHEMATICS AND COMPUTING↗

Glass-ceramic matrix composite feedstock and forming

A method of forming a part includes forming a glass-ceramic matrix composite material to form a pre-consolidated feedstock sheet with a pre-determined shape. The pre-consolidated feedstock sheet is sectioned into a first piece of pre-consolidated feedstock sheet and a second piece of pre-consolidated feedstock sheet. The first piece of pre-consolidated feedstock sheet and a second piece of pre-consolidated feedstock sheet are assembled with a second piece of pre-consolidated feedstock sheet to form a composite layup. The first piece of pre-consolidated feedstock sheet and the second piece of pre-consolidated feedstock sheet are joined by compressing the composite layup to form a glass-ceramic matrix composite part.

Gangloff, Jr., John J.↗

Improved Polypropylene Thermoformability through Polyethylene Layering

Due to its low cost, stiffness, and recyclability, isotactic polypropylene (iPP) is an excellent candidate for packaging applications. However, iPP is notoriously difficult to thermoform due to its low melt strength. The addition of just 10 thin layers of high-molecular-weight, linear low-density polyethylene (LLDPE) into iPP sheets by coextrusion significantly increased extensional viscosity and reduced sag. Both LLDPE and iPP were metallocene-catalyzed with excellent adhesion as measured in our previous work. Here, we performed a series of hot tensile tests and sheet sag measurements to determine the properties of the iPP sheet and the multilayer sheet between 130 and 180 °C. To evaluate the thermoformability of these multilayer sheets, truncated conical cups were positive vacuum formed at different temperatures and heating times, and the crush strength was measured. Cups that released easily from the mold with good shape retention and a crush strength within 80% of the maximum value were used to define a temperature–time thermoformability window. We estimated the maximum stress that occurred during the thermoforming process to be 5 MPa. Layer thicknesses before and after thermoforming were used to estimate an average strain of 0.78. The thin LLDPE layers decreased the yield stress below 5 MPa. This enabled thermoforming at sheet temperatures as low as 150 °C. The immiscible LLDPE interfaces increased extensional viscosity, which decreased sag in the multilayer sheets compared to iPP. This broadened the thermoforming range to temperatures as high as 180 °C and allowed longer heating times. These highly thermoformable, layered sheets may be recycled as iPP since they contain only 8% of LLDPE.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Materials Data on Ta36B4C35 by Materials Project

Ta26C25Ta9C8TaBC(B)2BC1 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of two boron molecules; one BC1 sheet oriented in the (0, 0, 1) direction; one Ta26C25 sheet oriented in the (0, 0, 1) direction; one Ta9C8 sheet oriented in the (0, 0, 1) direction; and one TaBC sheet oriented in the (0, 0, 1) direction. In the BC1 sheet, B3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. All B–C bond lengths are 1.83 Å. C4- is bonded in a distorted trigonal planar geometry to three equivalent B3+ atoms. In the Ta26C25 sheet, there are eighteen inequivalent Ta+3.56+ sites. In the first Ta+3.56+ site, Ta+3.56+ is bonded in a 3-coordinate geometry to three equivalent C4- atoms. There are one shorter (2.14 Å) and two longer (2.15 Å) Ta–C bond lengths. In the second Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 1°. All Ta–C bond lengths are 2.23 Å. In the third Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 1°. There are five shorter (2.25 Å) and one longer (2.26 Å) Ta–C bond lengths. In the fourth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. All Ta–C bond lengths are 2.25 Å. In the fifth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.24 Å) and three longer (2.26 Å) Ta–C bond lengths. In the sixth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.24 Å) and three longer (2.25 Å) Ta–C bond lengths. In the seventh Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the eighth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the ninth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the tenth Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. In the eleventh Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the twelfth Ta+3.56+ site, Ta+3.56+ is bonded to six equivalent C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the thirteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the fourteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the fifteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the sixteenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.23 Å. In the seventeenth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.23 Å) and two longer (2.24 Å) Ta–C bond lengths. In the eighteenth Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Ta–C bond lengths are 2.25 Å. There are fifteen inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the fifth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the sixth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the ninth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the tenth C4- site, C4- is bonded to six equivalent Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) C–Ta bond lengths. In the eleventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the twelfth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the thirteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifteenth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.25 Å. In the Ta9C8 sheet, there are nine inequivalent Ta+3.56+ sites. In the first Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are five shorter (2.24 Å) and one longer (2.25 Å) Ta–C bond lengths. In the second Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ta–C bond distances ranging from 2.23–2.26 Å. In the third Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. All Ta–C bond lengths are 2.26 Å. In the fourth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth Ta+3.56+ site, Ta+3.56+ is bonded in a distorted T-shaped geometry to three equivalent C4- atoms. In the sixth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.23 Å) and three longer (2.24 Å) Ta–C bond lengths. In the seventh Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.23 Å) and four longer (2.24 Å) Ta–C bond lengths. In the eighth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.24 Å) and two longer (2.25 Å) Ta–C bond lengths. In the ninth Ta+3.56+ site, Ta+3.56+ is bonded to six C4- atoms to form a mixture of corner and edge-sharing TaC6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–C bond lengths are 2.24 Å. There are eight inequivalent C4- sites. In the first C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the third C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.24 Å. In the fourth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. All C–Ta bond lengths are 2.24 Å. In the fifth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the eighth C4- site, C4- is bonded to six Ta+3.56+ atoms to form a mixture of corner and edge-sharing CTa6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the TaBC sheet, Ta+3.56+ is bonded in a single-bond geometry to one C4- atom. The Ta–C bond length is 2.08 Å. B3+ is bonded in a trigonal planar geometry to three equivalent C4- atoms. There are a spread of B–C bond distances ranging from 1.81–1.85 Å. C4- is bonded to one Ta+3.56+ and three equivalent B3+ atoms to form corner-sharing CTaB3 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on TeMoWSeS2 by Materials Project

WTe2MoSe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.45 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the MoSe2 sheet, Mo6+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.54 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W2+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the WTe2 sheet, W2+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Te2Mo3W(SeS2)2 by Materials Project

MoTe2MoSe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one MoTe2 sheet oriented in the (0, 0, 1) direction; and one WS2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo+4.67+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.44 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the MoSe2 sheet, Mo+4.67+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.54 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the MoTe2 sheet, Mo+4.67+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.70 Å. Te2- is bonded to three equivalent Mo+4.67+ atoms to form a mixture of distorted face and corner-sharing TeMo3 cuboctahedra. In the WS2 sheet, W2+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W2+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on MoW(SeS)2 by Materials Project

WSe2MoSe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; and one WSe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.43 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the MoSe2 sheet, Mo6+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.53 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W2+ is bonded to six equivalent S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.43 Å. S2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the WSe2 sheet, W2+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. All W–Se bond lengths are 2.54 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Te2MoW3(SeS2)2 by Materials Project

WTe2WSe2WS2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one WS2 sheet oriented in the (0, 0, 1) direction; one WSe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. There are three shorter (2.44 Å) and three longer (2.45 Å) Mo–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WS2 sheet, W+3.33+ is bonded to six S2- atoms to form distorted edge-sharing WS6 pentagonal pyramids. All W–S bond lengths are 2.45 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent W+3.33+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WSe2 sheet, W+3.33+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. All W–Se bond lengths are 2.55 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms. In the WTe2 sheet, W+3.33+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W+3.33+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W+3.33+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on TeMoWSe2S by Materials Project

WTe2WSe2MoSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one WSe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.46 Å. S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the MoSe2 sheet, Mo6+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.55 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WSe2 sheet, W2+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. All W–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the WTe2 sheet, W2+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. There are three shorter (2.71 Å) and three longer (2.72 Å) W–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on TeMoWSe2S by Materials Project

WTe2WSe2MoSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one WSe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.46 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the MoSe2 sheet, Mo6+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.55 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the WSe2 sheet, W2+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. All W–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the WTe2 sheet, W2+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. There are three shorter (2.71 Å) and three longer (2.72 Å) W–Te bond lengths. Te2- is bonded in a 12-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Te2MoWSeS by Materials Project

WTe2MoTe2WSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoTe2 sheet oriented in the (0, 0, 1) direction; one WSe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo6+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.47 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo6+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the MoTe2 sheet, Mo6+ is bonded to six Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Mo6+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent Mo6+ atoms. In the WSe2 sheet, W2+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing WSe6 pentagonal pyramids. There are three shorter (2.56 Å) and three longer (2.57 Å) W–Se bond lengths. Se2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms. In the WTe2 sheet, W2+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.72 Å. Te2- is bonded in a 12-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Te4Mo3W(SeS)2 by Materials Project

WTe2MoTe2MoSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one MoTe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo+4.67+ is bonded to six equivalent S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.47 Å. S2- is bonded in a distorted T-shaped geometry to three equivalent Mo+4.67+ atoms. In the MoSe2 sheet, Mo+4.67+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the MoTe2 sheet, Mo+4.67+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.71 Å. Te2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the WTe2 sheet, W2+ is bonded to six equivalent Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.72 Å. Te2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Te4Mo3W(SeS)2 by Materials Project

WTe2MoTe2MoSe2MoS2 is Molybdenite-derived structured and crystallizes in the trigonal P3m1 space group. The structure is two-dimensional and consists of one MoS2 sheet oriented in the (0, 0, 1) direction; one MoSe2 sheet oriented in the (0, 0, 1) direction; one MoTe2 sheet oriented in the (0, 0, 1) direction; and one WTe2 sheet oriented in the (0, 0, 1) direction. In the MoS2 sheet, Mo+4.67+ is bonded to six S2- atoms to form distorted edge-sharing MoS6 pentagonal pyramids. All Mo–S bond lengths are 2.47 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Mo+4.67+ atoms. In the MoSe2 sheet, Mo+4.67+ is bonded to six equivalent Se2- atoms to form distorted edge-sharing MoSe6 pentagonal pyramids. All Mo–Se bond lengths are 2.56 Å. Se2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the MoTe2 sheet, Mo+4.67+ is bonded to six Te2- atoms to form distorted edge-sharing MoTe6 pentagonal pyramids. All Mo–Te bond lengths are 2.71 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Mo+4.67+ atoms. In the second Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent Mo+4.67+ atoms. In the WTe2 sheet, W2+ is bonded to six Te2- atoms to form distorted edge-sharing WTe6 pentagonal pyramids. All W–Te bond lengths are 2.72 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 12-coordinate geometry to three equivalent W2+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent W2+ atoms.

36 MATERIALS SCIENCE↗