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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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17 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

An Atomistic Study of Reactivity in Solid-State Electrolyte Interphase Formation for Li/Li7P3S11

Lithium metal batteries offer superior volumetric and gravimetric specific capacities compared to those based on traditional graphite anodes. Although advancements in solid-state electrolytes address safety concerns, challenges remain, particularly regarding interphase formation in lithium metal anodes. This work presents a computational framework based on high-throughput first-principles density functional theory and machine-learning interatomic potentials (MLIPs) including automated iterative, active learning to enable robust computational exploration of interphase formation between lithium metal anodes and an inorganic solid-state electrolyte. As a demonstration, we apply the framework to a Li/Li7P3S11 interface and find that it accurately identifies the experimentally observed, thermodynamically stable interphase products as well as their overall spatial arrangement within a heterogeneous, amorphous layered structure, with Li2S domains of nanocrystallinity. Our simulations show two stages, a fast and slow diffusion reaction regime, that corroborate the relative phase formation rate of Li x P, Li2S, and Li3P. Using the Onsager transport theory, we capture time-dependent ionic diffusion within the reacting interface, including cross-correlation effects. We found that cross-correlation effects between Li-P and P-S ionic motion significantly influence P-ion diffusion, making it highly sensitive to the local environment and potentially leading to "kinetic trapping" of Li-P phases. The passivation of the interface is shown as the ionic fluxes all approach zero, effectively halting interphase growth.

Diffusion↗
DOE OSTI2022

Synthesis, Crystal and Electronic Structures, Nonlinear Optical Properties, and Magnetic Properties of Two Thiophosphates: KInP 2 S 7 and KCrP 2 S 7

Two thiophosphates, KInP 2 S 7 and KCrP 2 S 7 , were structurally characterized without investigating any optical properties. Herein in this work, KInP 2 S 7 and KCrP 2 S 7 were revisited to investigate their optical and magnetic properties, respectively. Pure polycrystalline samples and crystals of KInP 2 S 7 and KCrP 2 S 7 were grown by high temperature solid state reactions, where mm-sized crystals of KCrP 2 S 7 were collected. KCrP 2 S 7 is isostructural to KInP 2 S 7 , which features a layered structure. KInP 2 S 7 and KCrP 2 S 7 possess close relationship to the layered thiophosphate M 2 P 2 S 6 (M = Fe, Co, Zn, etc.). The bonding pictures of KInP 2 S 7 were studied using the electron localization function (ELF) coupled with crystal orbital Hamilton population (COHP) calculations. The intrinsically distorted [PS 4 ] tetrahedra and [InS 6 ] octahedra are made by strong covalent P-S interactions and ionic In-S interactions, respectively. Electronic structure analysis confirmed that the optical properties of KInP 2 S 7 are mainly contributed to by [PS 4 ] tetrahedra together with small amounts of the contributions coming from [InS 6 ] octahedra. Magnetic measurement on mm-sized crystals of KCrP 2 S 7 verified that there is an antiferromagnetic transition around 21 K, and the Cr atoms are trivalent. KInP 2 S 7 is predicated to be an indirect bandgap semiconductor of 2.38 eV, which is confirmed by the UV-Vis measurement of 2.4(1) eV. KInP 2 S 7 is not a type-I phase-matching material and exhibits moderate second harmonic generation (SHG) response (0.51 × AgGaS 2 , sample of particle size of 100 µm). The laser damage threshold (LDT) of KInP 2 S 7 is very high of 5.2 × AgGaS 2 . Bandgap engineering were undergone to enhance the SHG response of KInP 2 S 7 .

36 MATERIALS SCIENCE↗
DOE OSTI2021

Quantum Calculations of VX Ammonolysis and Hydrolysis Pathways via Hydrated Lithium Nitride

Recently, lithium nitride (Li 3 N) has been proposed as a chemical warfare agent (CWA) neutralization reagent for its ability to produce nucleophilic ammonia molecules and hydroxide ions in aqueous solution. Quantum chemical calculations can provide insight into the Li 3 N neutralization process that has been studied experimentally. Here, we calculate reaction-free energies associated with the Li3N-based neutralization of the CWA VX using quantum chemical density functional theory and ab initio methods. We find that alkaline hydrolysis is more favorable to either ammonolysis or neutral hydrolysis for initial P-S and P-O bond cleavages. Reaction-free energies of subsequent reactions are calculated to determine the full reaction pathway. Notably, products predicted from favorable reactions have been identified in previous experiments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1978

Mechanistic possibilities in prebiotic thiophosphate chemistry

The two types of thiophosphate reactivities were studied in a system that involves reactions of 5'-substituted adenosine derivatives. In this system, both nucleophilic displacement on carbon and P-S cleavage are possible. The products and possible mechanisms of cyclization experiments involving different leaving groups are reported. The data indicate superior reactivity of the 3'-OH of the ribonucleoside, although in most other systems the 2'-OH is found to show superior reactivity. It is suggested that thiophosphates might play a role in prebiotic activation and phosphorylation reactions.

Kapovits, I.↗
NASA NTRS1995

Identification of the in vivo truncation sites at the C-terminal region of alpha-A crystallin from aged bovine and human lens

Total alpha-A crystallin was purified from young versus old lens, followed by digestion with cyanogen bromide. Laser desorption mass spectrometry of the C-terminal fragment demonstrated age-dependent loss of one and five amino acids from the C-terminus of alpha-A crystallin from both bovine and human lens. These results demonstrate specific peptide bonds of alpha-A crystallin are cleaved during the aging process of the normal lens. The C-terminal region is cleaved in two places between the two hydroxyl-containing amino acids present in the sequence -P-S(T)-S-.

Non-NASA Center↗
DOE OSTI2020

Materials Data on P4S7 by Materials Project

P4S7 is High Pressure (4-7GPa) Tellurium structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four P4S7 clusters. there are four inequivalent P+3.50+ sites. In the first P+3.50+ site, P+3.50+ is bonded in a water-like geometry to two S2- atoms. Both P–S bond lengths are 2.12 Å. In the second P+3.50+ site, P+3.50+ is bonded in a water-like geometry to two S2- atoms. Both P–S bond lengths are 2.12 Å. In the third P+3.50+ site, P+3.50+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.14 Å. In the fourth P+3.50+ site, P+3.50+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.13 Å. There are seven inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two P+3.50+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two P+3.50+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two P+3.50+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two P+3.50+ atoms. In the fifth S2- site, S2- is bonded in a single-bond geometry to one P+3.50+ atom. In the sixth S2- site, S2- is bonded in a single-bond geometry to one P+3.50+ atom. In the seventh S2- site, S2- is bonded in a water-like geometry to two P+3.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P2S5 by Materials Project

P2S5 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two P2S5 clusters. there are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are one shorter (1.92 Å) and three longer (2.12 Å) P–S bond lengths. In the second P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are one shorter (1.92 Å) and three longer (2.12 Å) P–S bond lengths. In the third P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are one shorter (1.92 Å) and three longer (2.12 Å) P–S bond lengths. In the fourth P5+ site, P5+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are one shorter (1.92 Å) and three longer (2.12 Å) P–S bond lengths. There are ten inequivalent S2- sites. In the first S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the second S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the fifth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the sixth S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the seventh S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the eighth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom. In the ninth S2- site, S2- is bonded in a water-like geometry to two P5+ atoms. In the tenth S2- site, S2- is bonded in a single-bond geometry to one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P4S9 by Materials Project

P4S9 is black P structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four P4S9 clusters. there are four inequivalent P+4.50+ sites. In the first P+4.50+ site, P+4.50+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. All P–S bond lengths are 2.13 Å. In the second P+4.50+ site, P+4.50+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.12 Å. In the third P+4.50+ site, P+4.50+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.92–2.12 Å. In the fourth P+4.50+ site, P+4.50+ is bonded to four S2- atoms to form corner-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.12 Å. There are nine inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms. In the second S2- site, S2- is bonded in a single-bond geometry to one P+4.50+ atom. In the third S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms. In the fifth S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms. In the sixth S2- site, S2- is bonded in a single-bond geometry to one P+4.50+ atom. In the seventh S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms. In the eighth S2- site, S2- is bonded in a single-bond geometry to one P+4.50+ atom. In the ninth S2- site, S2- is bonded in a water-like geometry to two P+4.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PS by Materials Project

PS1 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of four tetraphosphorous tetrasulfide molecules. there are two inequivalent P2- sites. In the first P2- site, P2- is bonded in a distorted L-shaped geometry to one P2- and two S2+ atoms. The P–P bond length is 2.39 Å. Both P–S bond lengths are 2.12 Å. In the second P2- site, P2- is bonded in a distorted L-shaped geometry to one P2- and two S2+ atoms. Both P–S bond lengths are 2.12 Å. There are three inequivalent S2+ sites. In the first S2+ site, S2+ is bonded in a water-like geometry to two equivalent P2- atoms. In the second S2+ site, S2+ is bonded in a water-like geometry to two equivalent P2- atoms. In the third S2+ site, S2+ is bonded in a water-like geometry to two P2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P4S5 by Materials Project

P4S5 is alpha U structured and crystallizes in the monoclinic P2_1 space group. The structure is zero-dimensional and consists of two P4S5 clusters. there are four inequivalent P+2.50+ sites. In the first P+2.50+ site, P+2.50+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.13 Å) and one longer (2.17 Å) P–S bond lengths. In the second P+2.50+ site, P+2.50+ is bonded in a single-bond geometry to one S2- atom. The P–S bond length is 2.07 Å. In the third P+2.50+ site, P+2.50+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of P–S bond distances ranging from 1.94–2.13 Å. In the fourth P+2.50+ site, P+2.50+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are two shorter (2.13 Å) and one longer (2.16 Å) P–S bond lengths. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two P+2.50+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two P+2.50+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two P+2.50+ atoms. In the fourth S2- site, S2- is bonded in an L-shaped geometry to two P+2.50+ atoms. In the fifth S2- site, S2- is bonded in a single-bond geometry to one P+2.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P4S5 by Materials Project

P4S5 is alpha U structured and crystallizes in the monoclinic P2_1/m space group. The structure is zero-dimensional and consists of two tetraphosphorus pentasulfide molecules. there are three inequivalent P+2.50+ sites. In the first P+2.50+ site, P+2.50+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are two shorter (2.13 Å) and one longer (2.14 Å) P–S bond lengths. In the second P+2.50+ site, P+2.50+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are two shorter (2.13 Å) and one longer (2.14 Å) P–S bond lengths. In the third P+2.50+ site, P+2.50+ is bonded in a water-like geometry to two S2- atoms. There are one shorter (2.12 Å) and one longer (2.13 Å) P–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two P+2.50+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two P+2.50+ atoms. In the third S2- site, S2- is bonded in a water-like geometry to two P+2.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P2S7 by Materials Project

P2S7 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one P2S7 ribbon oriented in the (-1, 0, 1) direction. there are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four S+1.43- atoms to form edge-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.15 Å. In the second P5+ site, P5+ is bonded to four S+1.43- atoms to form edge-sharing PS4 tetrahedra. There are a spread of P–S bond distances ranging from 1.93–2.15 Å. There are seven inequivalent S+1.43- sites. In the first S+1.43- site, S+1.43- is bonded in a single-bond geometry to one P5+ atom. In the second S+1.43- site, S+1.43- is bonded in an L-shaped geometry to two equivalent P5+ atoms. In the third S+1.43- site, S+1.43- is bonded in a distorted water-like geometry to one P5+ and one S+1.43- atom. The S–S bond length is 2.06 Å. In the fourth S+1.43- site, S+1.43- is bonded in a water-like geometry to two S+1.43- atoms. The S–S bond length is 2.06 Å. In the fifth S+1.43- site, S+1.43- is bonded in a distorted water-like geometry to one P5+ and one S+1.43- atom. In the sixth S+1.43- site, S+1.43- is bonded in a single-bond geometry to one P5+ atom. In the seventh S+1.43- site, S+1.43- is bonded in an L-shaped geometry to two equivalent P5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P2S3 by Materials Project

P2S3 crystallizes in the orthorhombic Pmn2_1 space group. The structure is two-dimensional and consists of one P2S3 sheet oriented in the (0, 0, 1) direction. P3+ is bonded in a distorted L-shaped geometry to three S2- atoms. There are one shorter (2.13 Å) and two longer (2.15 Å) P–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in an L-shaped geometry to two equivalent P3+ atoms. In the second S2- site, S2- is bonded in a distorted single-bond geometry to two equivalent P3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P2S3 by Materials Project

P2S3 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of two P2S3 sheets oriented in the (0, 1, 0) direction. there are two inequivalent P3+ sites. In the first P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of P–S bond distances ranging from 2.14–2.16 Å. In the second P3+ site, P3+ is bonded in a trigonal non-coplanar geometry to three S2- atoms. There are a spread of P–S bond distances ranging from 2.14–2.16 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two P3+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two P3+ atoms. In the third S2- site, S2- is bonded in an L-shaped geometry to two P3+ atoms.

36 MATERIALS SCIENCE↗
NASA NTRS2003

Evaluation of an Ultra-Low Power Reed Solomon Encoder for NASA's Space Technology 5 Mission

Radiation test results and analyses are presented for ultra-low power Reed Solomon encoder circuits that are being considered for use on the Space Technology 5 (ST5) mission. The total ionizing dose tolerance is in excess of 100 krad(Si) and is due to the low supply voltage and the use of back-bias, which suppresses radiation-induced leakage currents in the n-channel devices. The circuits do not latch-up for ion LET values of at least 90 MeV-sq cm/mg. A hardened-by-design approach to SEU has achieved an upset threshold of about 20 MeV-sq cm/mg. The SEU rate expected for these circuits in the geosynchronous transfer orbit of ST5 is low.

Lei, K. E.↗
NASA NTRS2023

Improved Space Weather Observations and Modeling for Aviation Radiation

In recent years there has been a growing interest from the aviation community for space weather radiation forecasts tailored to the needs of the aviation industry. In 2019 several space weather centers began issuing advisories for the International Civil Aviation Organization alerting users to enhancements in the radiation environment at aviation flight levels. Due to a lack of routine observations, radiation modeling is required to specify the dose rates experienced by flight crew and passengers. While mature models exist, support for key observational inputs and further modeling advancements are needed. Observational inputs required from the ground-based neutron monitor network must be financially supported for research studies and operations to ensure real-time data is available for forecast operations and actionable end user decision making. An improved understanding of the geomagnetic field is required to reduce dose rate uncertainties in regions close to the open/closed geomagnetic field boundary, important for flights such as those between the continental US and Europe which operate in this region. Airborne radiation measurements, which are crucial for model validation and improvement, are lacking, particularly during solar energetic particle events. New measurement campaigns must be carried out to ensure progress and in situ atmospheric radiation measurements made available for real-time situational awareness. Furthermore, solar energetic particle forecasting must be improved to move aviation radiation nowcasts to forecasts in order to meet customer requirements for longer lead times for planning and mitigation.

space weather↗