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Results for “tellurium dioxide”

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.

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5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Uncertainties in tellurium-based dark matter searches stemming from nuclear structure uncertainties

Using tellurium dioxide as a target, we calculate uncertainties on 90% upper confidence limits of Galilean effective field theory (Galilean EFT) couplings to a weakly interacting massive particle (WIMP) dark matter candidate due to uncertainties in nuclear shell models. We find that these uncertainties in naturally occurring tellurium isotopes are comparable across the different Galilean EFT couplings to uncertainties in xenon, with some reaching over 100%. We also consider the effect these nuclear uncertainties have on estimates of the annual modulation of dark matter from these searches, finding that the uncertainties in the modulation amplitude are proportional to the nonmodulating upper confidence limit uncertainties. We also show that the determination of the modulation phase is insensitive to changes in the nuclear model for a given isotope.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

Shock compression of crystalline TeO 2 to the high-pressure fluid regime: Insights from ab initio molecular dynamics simulations

The shock response of fully-dense and porous crystalline tellurium dioxide (TeO 2 ⁠) to the high-pressure and high-temperature fluid regime was investigated within the framework of density functional theory with Mermin’s generalization to finite temperatures. The principal and porous shock Hugoniot curves were predicted from canonical ab initio molecular dynamics (AIMD) simulations, with the phase space sampled along isotherms up to 80 000 K, for densities ranging from ρ = 3 to 17 g/cm 3 . The polymorphs investigated are α-TeO 2 paratellurite (⁠P4 1 2 1 2), TeO 2 cotunnite (⁠Pnma⁠), and TeO 2 post-cotunnite (⁠P2 1 /m⁠). Based on the discontinuity found in the calculated U s – u p slope of TeO 2 post-cotunnite at a shock velocity of U s ≃ 8.35km/s and a particle velocity of u p ≃ 3.64 km/s, the shock melting temperature and pressure are predicted to be ≃ 6500 K and ≃ 170 GPa. Results from the AIMD simulations are in line with the static compression data of TeO 2 paratellurite and cotunnite, and with the recent shock Hugoniot data for single-crystal α- TeO 2 for pressures up to 85 GPa, obtained using the inclined-mirror method and the velocity interferometer system for any reflector combined with powder gun and two-stage light-gas gun.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2020

Materials Data on Te4As2S(OF6)2 by Materials Project

(Te)2AsTe2F6AsF6SO2 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four sulfur dioxide molecules, eight tellurium molecules, four AsF6 clusters, and four AsTe2F6 clusters. In each AsF6 cluster, As1+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.77–1.79 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In each AsTe2F6 cluster, As1+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.77–1.80 Å. Te4+ is bonded in a 1-coordinate geometry to one F1- atom. The Te–F bond length is 2.97 Å. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As1+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As1+ and two equivalent Te4+ atoms. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Te3As2S(OF6)2 by Materials Project

(Te)3AsTeF6AsTe2F6(AsF6)2(SO2)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four sulfur dioxide molecules, six tellurium molecules, four AsF6 clusters, two AsTe2F6 clusters, and two AsTeF6 clusters. In each AsF6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.77–1.79 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In each AsTe2F6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.75–1.80 Å. There are two inequivalent Te+2.67+ sites. In the first Te+2.67+ site, Te+2.67+ is bonded in a single-bond geometry to one F1- atom. The Te–F bond length is 2.84 Å. In the second Te+2.67+ site, Te+2.67+ is bonded in a single-bond geometry to one F1- atom. The Te–F bond length is 2.82 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ and one Te+2.67+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ and one Te+2.67+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In each AsTeF6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.76–1.80 Å. Te+2.67+ is bonded in a distorted single-bond geometry to one F1- atom. The Te–F bond length is 2.86 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ and one Te+2.67+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom.

36 MATERIALS SCIENCE↗