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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Mask-side Hyper-NA EUV imaging on the SHARP microscope

Hyper-NA, the prospective successor to high-numerical aperture (NA) extreme ultraviolet lithography (EUVL) could be inserted soon after 2030. Hyper-NA poses a number of challenges, including reduced depth of focus, amplified mask three-dimensional effects, and increased mask-side angular range. A Hyper-NA capable extreme ultraviolet (EUV) mask-imaging tool can address these challenges and accelerate research and development toward Hyper-NA. The Sharp High-Numerical Aperture Actinic Reticle Review Project (SHARP) EUV mask microscope is supporting mask-side high-NA imaging since 2015. Implementing mask-side Hyper-NA imaging in 2024 enables research and development toward the corresponding nodes of EUVL. Hyper-NA zoneplates at 0.75 4x/8x NA with a 6.7-deg chief ray angle and 0.85 4x/8x NA with a 7.4-deg chief ray angle are added to the SHARP microscope. Imaging at mask-side Hyper-NA is demonstrated. Imaging of 5-nm half-pitch (wafer scale) horizontal lines and spaces is demonstrated using dipole illumination. Imaging of 5-nm half-pitch (wafer scale) vertical lines and spaces is demonstrated using frequency-doubled imaging of 40-nm hp (mask scale) lines and spaces. Normalized image log slope (NILS) and modulation of Hyper-NA image data match closely to simulations for horizontal lines and spaces. A reduction in NILS of 0.3 or less is observed for vertical lines and spaces in the two-beam imaging regime. Through-focus image data are discussed, comparing different dipole sources and mask-side NAs. Mask-side Hyper-NA photomask imaging has been implemented and demonstrated on the SHARP microscope and is now available to users of the instrument.

Benk, Markus↗
DOE OSTI2020

Materials Data on Na(Mg4Al3)4 by Materials Project

Na(Mg4Al3)4 is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Na is bonded in a 12-coordinate geometry to eight Mg and five Al atoms. There are a spread of Na–Mg bond distances ranging from 3.09–3.64 Å. There are a spread of Na–Al bond distances ranging from 3.01–3.18 Å. There are ten inequivalent Mg sites. In the first Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.08–3.17 Å. There are a spread of Mg–Al bond distances ranging from 2.92–3.18 Å. In the second Mg site, Mg is bonded in a 12-coordinate geometry to four Mg and twelve Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.13–3.15 Å. There are a spread of Mg–Al bond distances ranging from 3.15–3.22 Å. In the third Mg site, Mg is bonded in a 10-coordinate geometry to one Na, three Mg, and six Al atoms. Both Mg–Mg bond lengths are 3.06 Å. There are a spread of Mg–Al bond distances ranging from 3.06–3.14 Å. In the fourth Mg site, Mg is bonded in a 11-coordinate geometry to one Na, four Mg, and six Al atoms. Both Mg–Mg bond lengths are 3.06 Å. There are a spread of Mg–Al bond distances ranging from 3.09–3.11 Å. In the fifth Mg site, Mg is bonded in a 12-coordinate geometry to one Na, six Mg, and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.07–3.20 Å. There are a spread of Mg–Al bond distances ranging from 2.93–3.25 Å. In the sixth Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.15–3.17 Å. There are a spread of Mg–Al bond distances ranging from 2.92–3.19 Å. In the seventh Mg site, Mg is bonded in a 12-coordinate geometry to one Na, six Mg, and five Al atoms. There are a spread of Mg–Mg bond distances ranging from 3.15–3.18 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.22 Å. In the eighth Mg site, Mg is bonded in a 10-coordinate geometry to four Mg and six Al atoms. Both Mg–Mg bond lengths are 3.06 Å. There are a spread of Mg–Al bond distances ranging from 3.06–3.13 Å. In the ninth Mg site, Mg is bonded in a 12-coordinate geometry to seven Mg and five Al atoms. The Mg–Mg bond length is 3.13 Å. There are a spread of Mg–Al bond distances ranging from 2.91–3.20 Å. In the tenth Mg site, Mg is bonded in a 12-coordinate geometry to one Na, six Mg, and five Al atoms. There are a spread of Mg–Al bond distances ranging from 2.95–3.18 Å. There are seven inequivalent Al sites. In the first Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. There are one shorter (2.69 Å) and two longer (2.77 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 11-coordinate geometry to one Na, seven Mg, and three Al atoms. There are a spread of Al–Al bond distances ranging from 2.72–2.77 Å. In the third Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.78 Å. In the fourth Al site, Al is bonded in a distorted q6 geometry to one Na, seven Mg, and three Al atoms. There are one shorter (2.69 Å) and one longer (2.79 Å) Al–Al bond lengths. In the fifth Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms. The Al–Al bond length is 2.77 Å. In the sixth Al site, Al is bonded in a 11-coordinate geometry to one Na, seven Mg, and three Al atoms. In the seventh Al site, Al is bonded in a 11-coordinate geometry to eight Mg and three Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na by Materials Project

Na is alpha Samarium structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to twelve Na atoms to form a mixture of corner, edge, and face-sharing NaNa12 cuboctahedra. There are six shorter (3.70 Å) and six longer (3.76 Å) Na–Na bond lengths. In the second Na site, Na is bonded to twelve Na atoms to form a mixture of corner, edge, and face-sharing NaNa12 cuboctahedra. There are three shorter (3.70 Å) and six longer (3.76 Å) Na–Na bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na by Materials Project

Na is alpha La structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to twelve Na atoms to form a mixture of edge, corner, and face-sharing NaNa12 cuboctahedra. There are six shorter (3.69 Å) and six longer (3.73 Å) Na–Na bond lengths. In the second Na site, Na is bonded to twelve Na atoms to form a mixture of edge, corner, and face-sharing NaNa12 cuboctahedra. All Na–Na bond lengths are 3.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na by Materials Project

Na crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded in a 8-coordinate geometry to eight Na atoms. There are a spread of Na–Na bond distances ranging from 3.47–3.75 Å. In the second Na site, Na is bonded in a 8-coordinate geometry to eight Na atoms. Both Na–Na bond lengths are 3.68 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na by Materials Project

Na crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to twelve equivalent Na atoms to form a mixture of face and edge-sharing NaNa12 cuboctahedra. All Na–Na bond lengths are 3.77 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six Na atoms. Both Na–Na bond lengths are 3.37 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na by Materials Project

Na is beta structured and crystallizes in the cubic P4_132 space group. The structure is three-dimensional. there are two inequivalent Na sites. In the first Na site, Na is bonded to twelve Na atoms to form a mixture of face, edge, and corner-sharing NaNa12 cuboctahedra. There are a spread of Na–Na bond distances ranging from 3.71–3.86 Å. In the second Na site, Na is bonded to twelve Na atoms to form a mixture of distorted face, edge, and corner-sharing NaNa12 cuboctahedra. All Na–Na bond lengths are 3.41 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Molecular structure and catalytic promotional effect of Mn on supported Na 2 WO 4 /SiO 2 catalysts for oxidative coupling of methane (OCM) reaction

The structure and promotional effect of Mn in supported Mn-Na 2 WO 4 /SiO 2 catalysts for the oxidative coupling of methane (OCM) reaction has been debated for a longtime in the literature. In the current investigation, with the aid of multiple in-situ characterization studies, we show that the freshly calcined supported 1.2Mn-5Na 2 WO 4 /SiO 2 catalyst possesses crystalline Na 2 WO 4 , Mn 2 O 3 and SiO 2 (cristobalite phase) along with surface MnO x and Na-WO x sites at low temperature and oxidizing environments. Under the OCM reaction environment (T>800°C), the crystalline Na 2 WO 4 phase melts and Mn 2 O 3 phase reduces. In contrast, the surface MnO x and Na-WO x sites exhibit excellent thermal and chemical stability. Exposure of the 1.2Mn-5Na 2 WO 4 /SiO 2 catalyst to the OCM reaction environment redisperses the molten Na 2 WO 4 phase on the SiO 2 support to form new surface WO x sites. Interestingly, the stable MnO x species interacts with both molten Na 2 WO 4 phase and surface Na-WO x sites during OCM reaction. Controlled transient kinetic experiments in TAP and detailed steady state OCM fixed-bed reaction studies reveal the role and promotional effect of Mn in the 1.2Mn-5Na 2 WO 4 /SiO 2 catalyst. The W-oxides (both molten Na 2 WO 4 and surface Na-WO x sites) are the active sites for the catalytic OCM reaction and the MnO x species only function as promoters. The promotion of MnO x strongly depends on the gas phase O 2 partial pressure and the MnO x species act as mediators for oxygen exchange between the gas phase molecular O 2 and catalyst lattice oxygen. In conclusion, the temperature dependent MnO x promotion reveals that the MnO x species selectively promote the molten Na 2 WO 4 phase at lower reaction temperature and the surface Na-WO x sites at higher temperature.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Structure Tuning, Strong Second Harmonic Generation Response, and High Optical Stability of the Polar Semiconductors Na 1- x K x AsQ 2

We report the mixed cation compounds Na 1-x K x AsSe 2 (x = 0.8, 0.65, 0.5) and Na 0.1 K 0.9 AsS 2 crystallize in the polar noncentrosymmetric space group Cc. The AAsQ(2) (A = alkali metals, Q = S, Se) family features one-dimensional (1D) 1 / ∞ [AQ 2 - ] chains comprising corner-sharing pyramidal AQ 3 units in which the packing of these chains is dependent on the alkali metals. The parallel 1 / ∞ [AQ(2) - ] chains interact via short As ∙∙∙Se contacts, which increase in length when the fraction of K atoms is increased. The increase in the As ∙∙∙Se interchain distance increases the band gap from 1.75 eV in γ-NaAsSe 2 to 2.01 eV in Na 0.35 K 0.65 AsSe 2 , 2.07 eV in Na 0.2 K 0.8 AsSe 2 , and 2.18 eV in Na 0.1 K 0.9 AsS 2 . The Na 1-x K x AsSe 2 (x = 0.8, 0.65) compounds melt congruently at approximately 316 °C. Wavelength-dependent second harmonic generation (SHG) measurements on powder samples of Na 1-x K x AsSe 2 (x = 0.8, 0.65, 0.5) and Na 0.1 K 0.9 AsS 2 suggest that Na 0.2 K 0.8 AsSe 2 and Na 0.1 K 0.9 AsS 2 have the highest SHG response and exhibit significantly higher laser-induced damage thresholds (LIDTs). Theoretical SHG calculations on Na 0.5 K 0.5 AsSe 2 confirm its SHG response with the highest value of d 33 = 22.5 pm/V χ 333 (2) = 45.0 pm/V). The effective nonlinearity for a randomly oriented powder is calculated to be d eff = 18.9 pm/V χ eff (2) = 37.8 pm/V), which is consistent with the experimentally obtained value of d eff = 16.5 pm/V χ eff (2) = 33.0 pm/V). Three-photon absorption is the dominant mechanism for the optical breakdown of the compounds under intense excitation at 1580 nm, with Na 0.2 K 0.8 AsSe 2 exhibiting the highest stability.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Flux-assisted polytypism in the [Na 2 Cl]GaQ 2 heterolayered salt-inclusion chalcogenide family

Two polytypic heterolayered salt-inclusion chalcogenides, o-[Na 2 Cl]GaQ 2 and t-[Na 2 Cl]GaQ 2 , were obtained via a NaCl/NaI flux-assisted synthesis, as part of an investigation of the Na–Ga–Q (Q = S and Se) system. The use of a different flux, NaBr/NaI, in the Na–Ga–Se system did not lead to the formation of salt-inclusion phases, but instead the novel Na 2 GaSe 3 and Na 4 Ga 2 Se 5 phases were obtained. Thermal and electronic properties of [Na 2 Cl]GaS 2 materials were investigated with differential scanning calorimetry, post-quenching ex situ powder X-ray diffraction (PXRD), high-temperature PXRD, and enthalpy and electronic structure calculations via density functional theory. Those studies determined the absence of any temperature-induced phase transition between the o-[Na 2 Cl]GaS 2 and t-[Na 2 Cl]GaS 2 polytypic compounds. Moreover, herein we probed the suitability of the heterolayered [Na 2 Cl]GaS 2 single crystals as a sorbent for UO 2 2+ uptake and monitored this process by energy-dispersive and infrared spectroscopies and PXRD, which revealed that the [Na 2 Cl]+ insert could be exchanged with UO 2 2+ on the surface while the UO 2 2+ intercalation decomposes the [Na 2 Cl]GaS 2 structure.

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

Materials Data on Na(LiSi2)3 by Materials Project

Na(LiSi2)3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Na is bonded in a 12-coordinate geometry to four Li and eight Si atoms. There are two shorter (3.08 Å) and two longer (3.12 Å) Na–Li bond lengths. There are a spread of Na–Si bond distances ranging from 3.13–3.32 Å. There are three inequivalent Li sites. In the first Li site, Li is bonded in a 4-coordinate geometry to two equivalent Na and five Si atoms. There are a spread of Li–Si bond distances ranging from 2.68–2.96 Å. In the second Li site, Li is bonded in a 4-coordinate geometry to two equivalent Na and six Si atoms. There are a spread of Li–Si bond distances ranging from 2.55–2.94 Å. In the third Li site, Li is bonded in a 7-coordinate geometry to nine Si atoms. There are a spread of Li–Si bond distances ranging from 2.62–3.06 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to five Li and four Si atoms. There are three shorter (2.41 Å) and one longer (2.45 Å) Si–Si bond lengths. In the second Si site, Si is bonded in a 7-coordinate geometry to one Na, two equivalent Li, and four Si atoms. There are two shorter (2.39 Å) and one longer (2.45 Å) Si–Si bond lengths. In the third Si site, Si is bonded in a 7-coordinate geometry to one Na, two equivalent Li, and four Si atoms. There are two shorter (2.38 Å) and one longer (2.45 Å) Si–Si bond lengths. In the fourth Si site, Si is bonded in a 9-coordinate geometry to two equivalent Na, five Li, and two equivalent Si atoms. In the fifth Si site, Si is bonded in a 8-coordinate geometry to two equivalent Na, three Li, and three Si atoms. In the sixth Si site, Si is bonded in a 8-coordinate geometry to two equivalent Na, three equivalent Li, and three Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Elastic NaxMoS2-carbon-BASE triple interface direct robust solid-solid interface for all-solid-state Na-S batteries

The promises of all-solid-state (ASS) sodium batteries for the next generation energy storage are widely recognized but their developments have been severely constrained by the difficulties to design favorable solid-solid interfaces for unhindered Na-ion transport. Using the most promising ß?-Al2O3 solid state electrolyte (BASE) as a platform, we demonstrate here a triple nanojunction strategy that provides simultaneous strong Na adhesion and continuous Na-ions diffusion at solid-solid interface. Such triple junctions (NaxMoS2-carbon-BASE) were constructed by adhering ternary composite Na anodes containing dispersed 3 wt% MoS2 and 3 wt% carbon on BASE, and provide nearly complete adhesion of Na on BASE with a much smaller contact angle (~ 45o vs. 120o of pristine Na). The composite Na anodes exhibited ~ 3 times improved elastic property and the synergy of NaxMoS2 and carbon provides the required ionic and electronic diffusion channels at solid-solid interface, which significantly improve Na utilization and resist premature failure due to loss of solid-solid contact as Na shrink during high capacity stripping. As a result, Na metal at the triple junction exhibited more than five time reduced charge transfer resistance and at least 200 hours stable battery cycling at practical current densities. The novel anode architecture also enabled high capacity cycling of prototype ASS sodium sulfur batteries when coupled with advanced sulfur cathodes containing intrinsic Na-ions diffusion channels and redox catalytic mediators, leading to stable cycling with specific capacity of 1110 mAh g-1.

ß”-Al2O3 solid electrolyte, solid state batteries,↗
DOE OSTI2023

A New Sodium Thioborate Fast Ion Conductor: Na 3 B 5 S 9

Abstract We report a new sodium fast‐ion conductor, Na 3 B 5 S 9 , that exhibits a high Na ion total conductivity of 0.80 mS cm −1 (sintered pellet; cold‐pressed pellet=0.21 mS cm −1 ). The structure consists of corner‐sharing B 10 S 20 supertetrahedral clusters, which create a framework that supports 3D Na ion diffusion channels. The Na ions are well‐distributed in the channels and form a disordered sublattice spanning five Na crystallographic sites. The combination of structural elucidation via single crystal X‐ray diffraction and powder synchrotron X‐ray diffraction at variable temperatures, solid‐state nuclear magnetic resonance spectra and ab initio molecular dynamics simulations reveal high Na‐ion mobility (predicted conductivity: 0.96 mS cm −1 ) and the nature of the 3D diffusion pathways. Notably, the Na ion sublattice orders at low temperatures, resulting in isolated Na polyhedra and thus much lower ionic conductivity. This highlights the importance of a disordered Na ion sublattice—and existence of well‐connected Na ion migration pathways formed via face‐sharing polyhedra—in dictating Na ion diffusion.

Zhou, Laidong↗
DOE OSTI2023

A New Sodium Thioborate Fast Ion Conductor: Na 3 B 5 S 9

Abstract We report a new sodium fast‐ion conductor, Na 3 B 5 S 9 , that exhibits a high Na ion total conductivity of 0.80 mS cm −1 (sintered pellet; cold‐pressed pellet=0.21 mS cm −1 ). The structure consists of corner‐sharing B 10 S 20 supertetrahedral clusters, which create a framework that supports 3D Na ion diffusion channels. The Na ions are well‐distributed in the channels and form a disordered sublattice spanning five Na crystallographic sites. The combination of structural elucidation via single crystal X‐ray diffraction and powder synchrotron X‐ray diffraction at variable temperatures, solid‐state nuclear magnetic resonance spectra and ab initio molecular dynamics simulations reveal high Na‐ion mobility (predicted conductivity: 0.96 mS cm −1 ) and the nature of the 3D diffusion pathways. Notably, the Na ion sublattice orders at low temperatures, resulting in isolated Na polyhedra and thus much lower ionic conductivity. This highlights the importance of a disordered Na ion sublattice—and existence of well‐connected Na ion migration pathways formed via face‐sharing polyhedra—in dictating Na ion diffusion.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Polymorphism and phase transitions in Na 2 U 2 O 7 from density functional perturbation theory

Polymorphism and phase transitions in sodium diuranate, Na 2 U 2 O 7 , are investigated with density functional perturbation theory (DFPT). Thermal properties of crystalline α-, β- and γ-Na 2 U 2 O 7 polymorphs are predicted from DFPT phonon calculations, i.e., the first time for the high-temperature γ-Na 2 U 2 O 7 phase (R$\bar{3}$ with combining macron]m symmetry). The standard molar isochoric heat capacities predicted within the quasi-harmonic approximation are C p (298.15K)= 219.4 and 220.9 J K -1 mol -1 mfor P21/a α-Na 2 U 2 O 7 and C2/m β-Na 2 U 2 O 7 , respectively. Gibbs free energy calculations reveal that α-Na 2 U 2 O 7 (P2 1 /a) and β-Na 2 U 2 O 7 (C2/m) are almost energetically degenerate at low temperature, with β-Na 2 U 2 O 7 becoming slightly more stable than α-Na 2 U 2 O 7 as temperature increases. Here these findings are consistent with XRD data showing a mixture of α and β phases after cooling of γ-Na 2 U 2 O 7 to room temperature and the observation of a sluggish α → β phase transition above ca. 600 K. A recently observed α-Na 2 U 2 O 7 structure with P21 symmetry is also shown to be metastable at low temperature. Based on Gibbs free energy, no direct β → γ solid-solid phase transition is predicted at high temperature, although some experiments reported the existence of such phase transition around 1348 K. This, along with recent experiments, suggests the occurrence of a multi-step process consisting of initial β-phase decomposition, followed by recrystallization into γ-phase as temperature increases.

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

Materials Data on Na(BH)6 by Materials Project

Na(BH)5BH crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four boranediylradical molecules and two Na(BH)5 clusters. In each Na(BH)5 cluster, Na is bonded in a 6-coordinate geometry to six H atoms. There are a spread of Na–H bond distances ranging from 2.28–2.54 Å. There are five inequivalent B sites. In the first B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the second B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the third B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the fourth B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the fifth B site, B is bonded in a single-bond geometry to one H atom. The B–H bond length is 1.21 Å. There are five inequivalent H sites. In the first H site, H is bonded in a water-like geometry to one Na and one B atom. In the second H site, H is bonded in a water-like geometry to one Na and one B atom. In the third H site, H is bonded in a distorted water-like geometry to one Na and one B atom. In the fourth H site, H is bonded in a distorted single-bond geometry to two equivalent Na and one B atom. In the fifth H site, H is bonded in a water-like geometry to one Na and one B atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na(SeO3)4 by Materials Project

Na(SeO3)4 crystallizes in the monoclinic Pc space group. The structure is one-dimensional and consists of two Na(SeO3)4 ribbons oriented in the (1, 0, 0) direction. Na is bonded to six O atoms to form distorted NaO6 octahedra that share a cornercorner with one SeO4 tetrahedra and an edgeedge with one SeO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.32–2.90 Å. There are four inequivalent Se sites. In the first Se site, Se is bonded to four O atoms to form SeO4 tetrahedra that share a cornercorner with one NaO6 octahedra and an edgeedge with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 73°. There are a spread of Se–O bond distances ranging from 1.63–1.86 Å. In the second Se site, Se is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.62 Å) and two longer (1.63 Å) Se–O bond length. In the third Se site, Se is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Se–O bond distances ranging from 1.65–1.85 Å. In the fourth Se site, Se is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.62 Å) and two longer (1.63 Å) Se–O bond length. There are twelve inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Na and one Se atom. In the second O site, O is bonded in a distorted water-like geometry to one Na and one Se atom. In the third O site, O is bonded in a bent 120 degrees geometry to one Na and one Se atom. In the fourth O site, O is bonded in a single-bond geometry to one Se atom. In the fifth O site, O is bonded in a single-bond geometry to one Se atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Na and one Se atom. In the seventh O site, O is bonded in a single-bond geometry to one Se atom. In the eighth O site, O is bonded in a bent 120 degrees geometry to one Na and one Se atom. In the ninth O site, O is bonded in a single-bond geometry to one Se atom. In the tenth O site, O is bonded in a 2-coordinate geometry to one Na and two Se atoms. In the eleventh O site, O is bonded in a single-bond geometry to one Se atom. In the twelfth O site, O is bonded in a single-bond geometry to one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na(MoSe)3 by Materials Project

Na(MoSe)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na is bonded in a 12-coordinate geometry to three Mo and nine Se atoms. All Na–Mo bond lengths are 3.66 Å. There are a spread of Na–Se bond distances ranging from 3.28–3.50 Å. There are three inequivalent Mo sites. In the first Mo site, Mo is bonded in a distorted see-saw-like geometry to one Na and four Se atoms. There are two shorter (2.64 Å) and two longer (2.72 Å) Mo–Se bond lengths. In the second Mo site, Mo is bonded in a distorted see-saw-like geometry to one Na and four Se atoms. There are two shorter (2.64 Å) and two longer (2.72 Å) Mo–Se bond lengths. In the third Mo site, Mo is bonded in a distorted see-saw-like geometry to one Na and four Se atoms. There are two shorter (2.64 Å) and two longer (2.72 Å) Mo–Se bond lengths. There are three inequivalent Se sites. In the first Se site, Se is bonded in a 7-coordinate geometry to three equivalent Na and four Mo atoms. In the second Se site, Se is bonded in a 7-coordinate geometry to three equivalent Na and four Mo atoms. In the third Se site, Se is bonded in a 7-coordinate geometry to three equivalent Na and four Mo atoms.

36 MATERIALS SCIENCE↗