Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Te”

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 1,531 records · Page 85
All sourcesNASA NTRSDOE OSTI
NASA NTRS2017

Milli-Watt Radioisotope Power to Enable Small, Long-Term Robotic “Probe” Space Exploration

Milli-watt Radioisotope Power Systems (RPS) based on Radioisotope Heater Units (RHUs) could be an ideal power source for certain spacecraft that cannot use solar power due to large distances from the sun, or other environmental constraints, and where they enable or significantly enhance the ability of a mission to meet its scientific or operational goals. Various modular, compact RHU-based thermoelectric (TE) generator concepts developed or derived from current NASA Small Business Innovation Research (SBIR) projects satisfying this need have been investigated. These modular, compact and low mass power systems could support small, highly-mobile robotic exploration packages, and could be incorporated into different robotic package concepts, spacecraft or satellites. Current modular RPS design concepts with 40mW, 80mW and 120mW power levels use RHUs and Bi2Te3 TE converters. Skutterudites materials could be used in the future if new higher thermal energy output and higher temperature miniature heat sources were developed, for example, using technologies currently in the General Purpose Heat Source (GPHS) used in higher electric power output RTGs. Small (a.k.a., “mice-like”) robotic packages could effectively utilize these RHU-driven power levels to accommodate crawling, climbing, monitoring, taking measurements, and communicating during long-term planetary missions aimed at gathering environmental and geologic data (i.e., over multiple decades). Waste heat from the cold side of the TE converter could also be directed toward the electronics and / or energy storage (e.g. batteries) to keep them within design temperature ranges. In addition to power generation and electronics / battery heating, the RHU / TE configuration could be designed to survive an external 500°C bake out procedure for critical spacecraft sterilization, environmental certification and planetary protection. Analytical studies have been performed to optimize various design configurations for power, mass, volume and robotic mobility. Specific power (mW/kg) and volumetric specific power (mW/cm3) characteristics of various design configurations will be presented and key conceptual design tradeoffs will be discussed. Hot- and cold-side thermal interfaces required to meet power and mass goals and associated design sensitivities will also be discussed. RHU / TE systems must overcome critical design challenges to survive high-g loadings in some robotic applications and we will examine the mass impacts required to satisfy various dynamic loading environments up to 10,000 g’s. Power can be generated for a minimum of 30 years or more using plutonium-238 dioxide heat sources (given that Pu-238 has an 87.7 year half-life) with some reduction in power as the heat source naturally degrades.

Bahrami, Poyan↗
DOE OSTI2022

Integration of Thermoelectric Modules to Vapor Compression Systems

This paper describes the technology of a thermoelectric (TE) integrated heat pump. It uses a TE heat pump to subcool the refrigerant liquid before entering the evaporator to enlarge the evaporating capacity; and elevate the heat in the refrigerant flow to a supplemental heating coil and discharge the capacity to the indoor air flow. Using the DOE/ORNL Heat Pump Design Model, four system configurations were modelled on a baseline two-speed heat pump, the baseline heat pump with adding a supplemental coil, the TE integrated heat pump having one stage TE heating to control a 20R liquid refrigerant temperature drop; and having two stages TE heating to control up to 40R temperature drop. The system models were used to produce performance curves for EnergyPlus building energy simulations. We selected template residential buildings, poorly insulated: pre-1990 buildings, and well-insulated: IECC2021 buildings; in five cold climate zones: 5A, 5B, 6A, 6B, 7. The building energy simulations demonstrated energy saving potentials, utility cost reductions and estimated payback periods.

Shen, Bo↗
DOE OSTI2023

Modelling and Simulation of a Thermoelectric Heat Pump with Micro-Channel Heat Transfer

Thermoelectric heat pumps (TEHPs) have advantages of modularity and simple design for heating and cooling in some applications. Models of thermoelectric (TE) heat pumps are widely studied. Nevertheless, most existing modeling work focuses on the TE material or air-sourced TE modules. TEHP modeling, especially the relationship between modules and heat exchangers, has not been comprehensively conducted. This work presents a water-to-water TEHP modeling framework that combines Goldsmid’s approach for TE material performance, Gnielinski’s correlation for convective heat transfer, and thermal balance theory for heat exchange networks. This combined framework provides an accurate theoretical analysis of the water-to-water TEHP system. Subsequently, the framework was used to empirically determine TE material properties (electric resistivity, thermal conductivity, and Seebeck coefficient) that minimize modeling errors versus experimentally observed values from the literature. Finally, an additional set of experimental TEHP data was used to validate the model, all with relative absolute deviations of approximately 10% when predicting heating capacity and 10%–20% when forecasting cooling capacity at a 30 K temperature lift. For future work, people can further develop models of TEHPs with an air-based heat sink on one side and water channels on the other side.

Wan, Hanlong↗
DOE OSTI2020

Materials Data on K2UTe3 by Materials Project

K2UTe3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six Te2- atoms to form distorted KTe6 octahedra that share corners with two equivalent KTe6 octahedra, corners with four equivalent UTe6 octahedra, edges with four equivalent UTe6 octahedra, and edges with eight KTe6 octahedra. The corner-sharing octahedra tilt angles range from 12–13°. There are a spread of K–Te bond distances ranging from 3.45–3.75 Å. In the second K1+ site, K1+ is bonded to six Te2- atoms to form KTe6 octahedra that share corners with two equivalent KTe6 octahedra, corners with four equivalent UTe6 octahedra, edges with four equivalent UTe6 octahedra, and edges with eight KTe6 octahedra. The corner-sharing octahedra tilt angles range from 11–15°. There are two shorter (3.40 Å) and four longer (3.70 Å) K–Te bond lengths. In the third K1+ site, K1+ is bonded to six Te2- atoms to form KTe6 octahedra that share corners with six KTe6 octahedra, edges with six KTe6 octahedra, and edges with six equivalent UTe6 octahedra. The corner-sharing octahedra tilt angles range from 13–15°. There are two shorter (3.45 Å) and four longer (3.49 Å) K–Te bond lengths. U4+ is bonded to six Te2- atoms to form UTe6 octahedra that share corners with six KTe6 octahedra, edges with three equivalent UTe6 octahedra, and edges with nine KTe6 octahedra. The corner-sharing octahedra tilt angles range from 11–13°. There are four shorter (3.09 Å) and two longer (3.10 Å) U–Te bond lengths. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to four K1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing TeK4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the second Te2- site, Te2- is bonded to four K1+ and two equivalent U4+ atoms to form a mixture of edge and corner-sharing TeK4U2 octahedra. The corner-sharing octahedra tilt angles range from 0–13°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KNdTe4 by Materials Project

KNdTe4 crystallizes in the tetragonal P4/nbm space group. The structure is three-dimensional. K1+ is bonded in a 8-coordinate geometry to eight equivalent Te1- atoms. All K–Te bond lengths are 3.71 Å. Nd3+ is bonded in a 8-coordinate geometry to eight equivalent Te1- atoms. All Nd–Te bond lengths are 3.29 Å. Te1- is bonded in a 5-coordinate geometry to two equivalent K1+, two equivalent Nd3+, and one Te1- atom. The Te–Te bond length is 2.83 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbNdTe4 by Materials Project

RbNdTe4 crystallizes in the tetragonal P4/nbm space group. The structure is three-dimensional. Rb1+ is bonded in a 8-coordinate geometry to eight equivalent Te1- atoms. All Rb–Te bond lengths are 3.84 Å. Nd3+ is bonded in a 8-coordinate geometry to eight equivalent Te1- atoms. All Nd–Te bond lengths are 3.29 Å. Te1- is bonded in a 5-coordinate geometry to two equivalent Rb1+, two equivalent Nd3+, and one Te1- atom. The Te–Te bond length is 2.83 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbSc5Te8 by Materials Project

RbSc5Te8 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Rb1+ is bonded in a distorted q6 geometry to ten Te2- atoms. There are a spread of Rb–Te bond distances ranging from 3.93–4.17 Å. There are three inequivalent Sc3+ sites. In the first Sc3+ site, Sc3+ is bonded to six Te2- atoms to form a mixture of edge, face, and corner-sharing ScTe6 octahedra. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Sc–Te bond distances ranging from 2.87–3.04 Å. In the second Sc3+ site, Sc3+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing ScTe6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are four shorter (2.92 Å) and two longer (2.95 Å) Sc–Te bond lengths. In the third Sc3+ site, Sc3+ is bonded to six Te2- atoms to form a mixture of edge, face, and corner-sharing ScTe6 octahedra. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Sc–Te bond distances ranging from 2.87–3.06 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to one Rb1+ and four Sc3+ atoms. In the second Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Rb1+ and three Sc3+ atoms. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Rb1+ and three equivalent Sc3+ atoms. In the fourth Te2- site, Te2- is bonded to five Sc3+ atoms to form distorted edge-sharing TeSc5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te2Ir by Materials Project

IrTe2 is Marcasite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ir4+ sites. In the first Ir4+ site, Ir4+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing IrTe6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are four shorter (2.68 Å) and two longer (2.70 Å) Ir–Te bond lengths. In the second Ir4+ site, Ir4+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing IrTe6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are a spread of Ir–Te bond distances ranging from 2.63–2.77 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ir4+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Ir4+ atoms. In the third Te2- site, Te2- is bonded in a 4-coordinate geometry to three Ir4+ and one Te2- atom. The Te–Te bond length is 2.99 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na3GeTe3 by Materials Project

Na3GeTe3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 pentagonal pyramids that share corners with six equivalent NaTe6 octahedra, corners with five equivalent NaTe5 square pyramids, edges with three equivalent NaTe6 pentagonal pyramids, an edgeedge with one NaTe5 square pyramid, faces with two equivalent NaTe6 octahedra, and a faceface with one NaTe5 square pyramid. The corner-sharing octahedra tilt angles range from 36–78°. There are a spread of Na–Te bond distances ranging from 3.19–3.56 Å. In the second Na1+ site, Na1+ is bonded to six Te2- atoms to form distorted NaTe6 octahedra that share corners with two equivalent NaTe6 octahedra, corners with six equivalent NaTe6 pentagonal pyramids, corners with three equivalent NaTe5 square pyramids, edges with two equivalent NaTe6 octahedra, edges with two equivalent NaTe5 square pyramids, faces with two equivalent NaTe6 pentagonal pyramids, and a faceface with one NaTe5 square pyramid. The corner-sharing octahedral tilt angles are 32°. There are a spread of Na–Te bond distances ranging from 3.19–3.57 Å. In the third Na1+ site, Na1+ is bonded to five Te2- atoms to form distorted NaTe5 square pyramids that share corners with three equivalent NaTe6 octahedra, corners with five equivalent NaTe6 pentagonal pyramids, corners with four equivalent NaTe5 square pyramids, edges with two equivalent NaTe6 octahedra, an edgeedge with one NaTe6 pentagonal pyramid, a faceface with one NaTe6 octahedra, and a faceface with one NaTe6 pentagonal pyramid. The corner-sharing octahedra tilt angles range from 41–55°. There are a spread of Na–Te bond distances ranging from 3.13–3.74 Å. Ge3+ is bonded in a trigonal non-coplanar geometry to three Te2- atoms. There are one shorter (2.61 Å) and two longer (2.62 Å) Ge–Te bond lengths. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six Na1+ and one Ge3+ atom to form distorted face-sharing TeNa6Ge pentagonal bipyramids. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to six Na1+ and one Ge3+ atom. In the third Te2- site, Te2- is bonded in a 6-coordinate geometry to five Na1+ and one Ge3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaTe4Ir by Materials Project

TaIrTe4 crystallizes in the orthorhombic Pmn2_1 space group. The structure is two-dimensional and consists of two TaIrTe4 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six Te2- atoms to form distorted TaTe6 octahedra that share edges with two equivalent IrTe6 octahedra and edges with four TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.67–2.93 Å. In the second Ta5+ site, Ta5+ is bonded to six Te2- atoms to form distorted TaTe6 octahedra that share edges with two equivalent IrTe6 octahedra and edges with four TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.67–2.92 Å. There are two inequivalent Ir3+ sites. In the first Ir3+ site, Ir3+ is bonded to six Te2- atoms to form IrTe6 octahedra that share edges with two equivalent TaTe6 octahedra and edges with four IrTe6 octahedra. There are a spread of Ir–Te bond distances ranging from 2.68–2.74 Å. In the second Ir3+ site, Ir3+ is bonded to six Te2- atoms to form IrTe6 octahedra that share edges with two equivalent TaTe6 octahedra and edges with four IrTe6 octahedra. There are a spread of Ir–Te bond distances ranging from 2.67–2.74 Å. There are eight inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Ta5+ and one Ir3+ atom. In the second Te2- site, Te2- is bonded in a distorted trigonal non-coplanar geometry to three Ta5+ atoms. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Ta5+ and one Ir3+ atom. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ir3+ atoms. In the fifth Te2- site, Te2- is bonded in a distorted trigonal non-coplanar geometry to three Ta5+ atoms. In the sixth Te2- site, Te2- is bonded in a 3-coordinate geometry to one Ta5+ and two equivalent Ir3+ atoms. In the seventh Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ir3+ atoms. In the eighth Te2- site, Te2- is bonded in a 3-coordinate geometry to one Ta5+ and two equivalent Ir3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsGaTe2 by Materials Project

CsGaTe2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of Cs–Te bond distances ranging from 3.90–4.31 Å. In the second Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of Cs–Te bond distances ranging from 3.97–4.32 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Te2- atoms to form corner-sharing GaTe4 tetrahedra. There are a spread of Ga–Te bond distances ranging from 2.65–2.70 Å. In the second Ga3+ site, Ga3+ is bonded to four Te2- atoms to form corner-sharing GaTe4 tetrahedra. There are a spread of Ga–Te bond distances ranging from 2.65–2.70 Å. There are five inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 2-coordinate geometry to four Cs1+ and two Ga3+ atoms. In the second Te2- site, Te2- is bonded in a 2-coordinate geometry to four Cs1+ and two equivalent Ga3+ atoms. In the third Te2- site, Te2- is bonded in a 2-coordinate geometry to four Cs1+ and two equivalent Ga3+ atoms. In the fourth Te2- site, Te2- is bonded in a 6-coordinate geometry to four Cs1+ and two Ga3+ atoms. In the fifth Te2- site, Te2- is bonded to four Cs1+ and two Ga3+ atoms to form a mixture of distorted corner and edge-sharing TeCs4Ga2 octahedra. The corner-sharing octahedral tilt angles are 8°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ba2Ge2Te5 by Materials Project

Ba2Ge2Te5 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to eight Te2- atoms. There are a spread of Ba–Te bond distances ranging from 3.54–3.89 Å. In the second Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine Te2- atoms. There are a spread of Ba–Te bond distances ranging from 3.58–4.05 Å. There are two inequivalent Ge3+ sites. In the first Ge3+ site, Ge3+ is bonded in a distorted trigonal non-coplanar geometry to three Te2- atoms. There are a spread of Ge–Te bond distances ranging from 2.64–2.67 Å. In the second Ge3+ site, Ge3+ is bonded in a trigonal non-coplanar geometry to three Te2- atoms. There are a spread of Ge–Te bond distances ranging from 2.62–2.65 Å. There are five inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 5-coordinate geometry to four Ba2+ and one Ge3+ atom. In the second Te2- site, Te2- is bonded in a 4-coordinate geometry to three Ba2+ and one Ge3+ atom. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Ba2+ and two Ge3+ atoms. In the fourth Te2- site, Te2- is bonded in a 5-coordinate geometry to four Ba2+ and one Ge3+ atom. In the fifth Te2- site, Te2- is bonded in a 5-coordinate geometry to four Ba2+ and one Ge3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KGaTe2 by Materials Project

KGaTe2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.71–3.74 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.58–3.73 Å. There are two inequivalent Ga3+ sites. In the first Ga3+ site, Ga3+ is bonded to four Te2- atoms to form corner-sharing GaTe4 tetrahedra. There are a spread of Ga–Te bond distances ranging from 2.65–2.67 Å. In the second Ga3+ site, Ga3+ is bonded to four Te2- atoms to form corner-sharing GaTe4 tetrahedra. There are a spread of Ga–Te bond distances ranging from 2.65–2.67 Å. There are five inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to two K1+ and two Ga3+ atoms. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to four K1+ and two Ga3+ atoms. In the third Te2- site, Te2- is bonded in a 4-coordinate geometry to two K1+ and two Ga3+ atoms. In the fourth Te2- site, Te2- is bonded in a 6-coordinate geometry to four K1+ and two equivalent Ga3+ atoms. In the fifth Te2- site, Te2- is bonded in a 6-coordinate geometry to four K1+ and two equivalent Ga3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KAlTe2 by Materials Project

KAlTe2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.57–3.72 Å. In the second K1+ site, K1+ is bonded in a 6-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.67–3.72 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four Te2- atoms to form corner-sharing AlTe4 tetrahedra. There are a spread of Al–Te bond distances ranging from 2.63–2.66 Å. In the second Al3+ site, Al3+ is bonded to four Te2- atoms to form corner-sharing AlTe4 tetrahedra. There are a spread of Al–Te bond distances ranging from 2.63–2.66 Å. There are five inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to two K1+ and two Al3+ atoms. In the second Te2- site, Te2- is bonded in a 2-coordinate geometry to four K1+ and two Al3+ atoms. In the third Te2- site, Te2- is bonded in a 4-coordinate geometry to two K1+ and two Al3+ atoms. In the fourth Te2- site, Te2- is bonded in a 2-coordinate geometry to four K1+ and two equivalent Al3+ atoms. In the fifth Te2- site, Te2- is bonded in a 2-coordinate geometry to four K1+ and two equivalent Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K3AlTe3 by Materials Project

K3AlTe3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven Te2- atoms. There are a spread of K–Te bond distances ranging from 3.62–4.24 Å. In the second K1+ site, K1+ is bonded to five Te2- atoms to form distorted KTe5 trigonal bipyramids that share corners with four equivalent AlTe4 tetrahedra, corners with two equivalent KTe5 trigonal bipyramids, an edgeedge with one AlTe4 tetrahedra, and an edgeedge with one KTe5 trigonal bipyramid. There are a spread of K–Te bond distances ranging from 3.50–3.66 Å. In the third K1+ site, K1+ is bonded in a 4-coordinate geometry to six Te2- atoms. There are a spread of K–Te bond distances ranging from 3.50–4.01 Å. Al3+ is bonded to four Te2- atoms to form AlTe4 tetrahedra that share corners with four equivalent KTe5 trigonal bipyramids, an edgeedge with one AlTe4 tetrahedra, and an edgeedge with one KTe5 trigonal bipyramid. There are a spread of Al–Te bond distances ranging from 2.61–2.71 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 7-coordinate geometry to five K1+ and two equivalent Al3+ atoms. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to six K1+ and one Al3+ atom. In the third Te2- site, Te2- is bonded in a 1-coordinate geometry to seven K1+ and one Al3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsHo3Te5 by Materials Project

CsHo3Te5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Cs1+ is bonded in a 7-coordinate geometry to seven Te2- atoms. There are a spread of Cs–Te bond distances ranging from 3.92–4.08 Å. There are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing HoTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. There are a spread of Ho–Te bond distances ranging from 3.02–3.17 Å. In the second Ho3+ site, Ho3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing HoTe6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ho–Te bond distances ranging from 3.03–3.18 Å. In the third Ho3+ site, Ho3+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing HoTe6 octahedra. The corner-sharing octahedral tilt angles are 11°. There are a spread of Ho–Te bond distances ranging from 3.04–3.12 Å. There are five inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to five Ho3+ atoms to form TeHo5 square pyramids that share a cornercorner with one TeCsHo4 trigonal bipyramid, edges with two equivalent TeHo5 square pyramids, and edges with two equivalent TeCsHo4 trigonal bipyramids. In the second Te2- site, Te2- is bonded to one Cs1+ and four Ho3+ atoms to form distorted TeCsHo4 trigonal bipyramids that share a cornercorner with one TeHo5 square pyramid, corners with two equivalent TeCsHo4 trigonal bipyramids, edges with two equivalent TeHo5 square pyramids, and edges with two equivalent TeCsHo4 trigonal bipyramids. In the third Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Ho3+ atoms. In the fourth Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Ho3+ atoms. In the fifth Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three Ho3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K2Cd3Te4 by Materials Project

K2Cd3Te4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to six Te2- atoms to form distorted KTe6 octahedra that share corners with twelve CdTe4 tetrahedra, edges with six KTe6 octahedra, and edges with three CdTe4 tetrahedra. There are a spread of K–Te bond distances ranging from 3.67–3.80 Å. In the second K1+ site, K1+ is bonded to six Te2- atoms to form distorted KTe6 octahedra that share corners with ten CdTe4 tetrahedra, edges with six KTe6 octahedra, and edges with four CdTe4 tetrahedra. There are a spread of K–Te bond distances ranging from 3.56–3.80 Å. There are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded to four Te2- atoms to form CdTe4 tetrahedra that share corners with eight KTe6 octahedra, corners with four CdTe4 tetrahedra, edges with two KTe6 octahedra, and edges with two CdTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–97°. There are a spread of Cd–Te bond distances ranging from 2.83–2.99 Å. In the second Cd2+ site, Cd2+ is bonded to four Te2- atoms to form CdTe4 tetrahedra that share corners with six KTe6 octahedra, corners with four equivalent CdTe4 tetrahedra, edges with three KTe6 octahedra, and edges with two equivalent CdTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 12–95°. There are a spread of Cd–Te bond distances ranging from 2.83–2.97 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 6-coordinate geometry to three K1+ and three Cd2+ atoms. In the second Te2- site, Te2- is bonded in a 6-coordinate geometry to three K1+ and three Cd2+ atoms. In the third Te2- site, Te2- is bonded to three K1+ and three Cd2+ atoms to form a mixture of distorted edge and corner-sharing TeK3Cd3 octahedra. The corner-sharing octahedra tilt angles range from 0–54°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TaTe2 by Materials Project

TaTe2 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one TaTe2 sheet oriented in the (2, 0, -1) direction. there are four inequivalent Ta4+ sites. In the first Ta4+ site, Ta4+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.70–2.94 Å. In the second Ta4+ site, Ta4+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.65–2.93 Å. In the third Ta4+ site, Ta4+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are a spread of Ta–Te bond distances ranging from 2.77–2.94 Å. In the fourth Ta4+ site, Ta4+ is bonded to six Te2- atoms to form distorted edge-sharing TaTe6 octahedra. There are four shorter (2.89 Å) and two longer (2.91 Å) Ta–Te bond lengths. There are six inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta4+ atoms. In the second Te2- site, Te2- is bonded in a distorted trigonal non-coplanar geometry to three Ta4+ atoms. In the third Te2- site, Te2- is bonded in a distorted trigonal non-coplanar geometry to three Ta4+ atoms. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta4+ atoms. In the fifth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta4+ atoms. In the sixth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Ta4+ atoms.

36 MATERIALS SCIENCE↗