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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Mn(NbS2)2 by Materials Project

Mn(NbS2)2 crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Mn(NbS2)2 sheet oriented in the (0, 0, 1) direction. Nb3+ is bonded in a rectangular see-saw-like geometry to four S2- atoms. There are one shorter (2.43 Å) and three longer (2.44 Å) Nb–S bond lengths. Mn2+ is bonded to six equivalent S2- atoms to form edge-sharing MnS6 octahedra. All Mn–S bond lengths are 2.34 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Nb3+ and three equivalent Mn2+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Nb3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(CuSe)2 by Materials Project

Mn(CuSe)2 crystallizes in the cubic F-43m space group. The structure is three-dimensional. Mn2+ is bonded in a 9-coordinate geometry to three equivalent Cu1+ and six Se2- atoms. All Mn–Cu bond lengths are 2.55 Å. There are three shorter (2.75 Å) and three longer (2.91 Å) Mn–Se bond lengths. There are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a 6-coordinate geometry to two equivalent Mn2+ and four Se2- atoms. There are two shorter (2.47 Å) and two longer (2.53 Å) Cu–Se bond lengths. In the second Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent Se2- atoms. All Cu–Se bond lengths are 2.46 Å. In the third Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent Se2- atoms. All Cu–Se bond lengths are 2.58 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms. In the second Se2- site, Se2- is bonded in a 7-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(CO)5 by Materials Project

Mn(CO)5 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight Mn(CO)5 clusters. Mn2+ is bonded in a square pyramidal geometry to five C+1.60+ atoms. There are a spread of Mn–C bond distances ranging from 1.82–1.86 Å. There are five inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(BO2)2 by Materials Project

Mn(BO2)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded in a 4-coordinate geometry to seven O2- atoms. There are a spread of Mn–O bond distances ranging from 2.14–2.74 Å. In the second Mn2+ site, Mn2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Mn–O bond distances ranging from 2.12–2.55 Å. There are four inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.48–1.51 Å. In the second B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.51 Å. In the third B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.47–1.50 Å. In the fourth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.48–1.51 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Mn2+ and two B3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Mn2+ and two B3+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mn2+ and two B3+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mn2+ and two B3+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Mn2+ and two B3+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Mn2+ and two B3+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Mn2+ and two B3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two Mn2+ and two B3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(BH4)2 by Materials Project

Mn(BH4)2 crystallizes in the tetragonal I4_1/acd space group. The structure is three-dimensional and consists of two Mn(BH4)2 frameworks. Mn2+ is bonded to eight H+0.50+ atoms to form distorted MnH8 hexagonal bipyramids that share edges with four equivalent BH4 tetrahedra. There are four shorter (2.05 Å) and four longer (2.10 Å) Mn–H bond lengths. B3- is bonded to four H+0.50+ atoms to form BH4 tetrahedra that share edges with two equivalent MnH8 hexagonal bipyramids. All B–H bond lengths are 1.23 Å. There are two inequivalent H+0.50+ sites. In the first H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mn2+ and one B3- atom. In the second H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mn2+ and one B3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(CuTe)2 by Materials Project

Mn(CuTe)2 crystallizes in the cubic F-43m space group. The structure is three-dimensional. Mn2+ is bonded in a 9-coordinate geometry to three equivalent Cu1+ and six Te2- atoms. All Mn–Cu bond lengths are 2.64 Å. There are three shorter (2.95 Å) and three longer (3.06 Å) Mn–Te bond lengths. There are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a 4-coordinate geometry to two equivalent Mn2+ and four Te2- atoms. There are two shorter (2.64 Å) and two longer (2.65 Å) Cu–Te bond lengths. In the second Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent Te2- atoms. All Cu–Te bond lengths are 2.57 Å. In the third Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent Te2- atoms. All Cu–Te bond lengths are 2.72 Å. There are two inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 4-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms. In the second Te2- site, Te2- is bonded in a 7-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(SbSe2)2 by Materials Project

Mn(SbSe2)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Mn2+ sites. In the first Mn2+ site, Mn2+ is bonded to six Se2- atoms to form MnSe6 octahedra that share corners with four equivalent SbSe6 octahedra, edges with two equivalent MnSe6 octahedra, and edges with six equivalent SbSe6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are two shorter (2.68 Å) and four longer (2.74 Å) Mn–Se bond lengths. In the second Mn2+ site, Mn2+ is bonded to six Se2- atoms to form MnSe6 octahedra that share corners with two equivalent SbSe6 octahedra, corners with four equivalent SbSe5 square pyramids, edges with two equivalent MnSe6 octahedra, and edges with six equivalent SbSe5 square pyramids. The corner-sharing octahedral tilt angles are 50°. There are two shorter (2.62 Å) and four longer (2.77 Å) Mn–Se bond lengths. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to five Se2- atoms to form SbSe5 square pyramids that share corners with two equivalent MnSe6 octahedra, corners with two equivalent SbSe6 octahedra, edges with three equivalent MnSe6 octahedra, and edges with four equivalent SbSe5 square pyramids. The corner-sharing octahedra tilt angles range from 11–60°. There are a spread of Sb–Se bond distances ranging from 2.63–3.14 Å. In the second Sb3+ site, Sb3+ is bonded to six Se2- atoms to form SbSe6 octahedra that share corners with three MnSe6 octahedra, corners with two equivalent SbSe5 square pyramids, edges with three equivalent MnSe6 octahedra, and edges with four equivalent SbSe6 octahedra. The corner-sharing octahedra tilt angles range from 8–50°. There are a spread of Sb–Se bond distances ranging from 2.68–3.33 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to one Mn2+ and three Sb3+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Mn2+ and three equivalent Sb3+ atoms to form a mixture of distorted edge and corner-sharing SeMn2Sb3 square pyramids. In the third Se2- site, Se2- is bonded to two equivalent Mn2+ and three equivalent Sb3+ atoms to form a mixture of distorted edge and corner-sharing SeMn2Sb3 square pyramids. In the fourth Se2- site, Se2- is bonded in a 3-coordinate geometry to one Mn2+ and two equivalent Sb3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(ReO5)2 by Materials Project

Mn(ReO5)2 crystallizes in the monoclinic C2/m space group. The structure is one-dimensional and consists of two Mn(ReO5)2 ribbons oriented in the (0, 1, 0) direction. Re+6.50+ is bonded to four O2- atoms to form ReO4 tetrahedra that share corners with two equivalent MnO6 octahedra. The corner-sharing octahedral tilt angles are 25°. There is two shorter (1.73 Å) and two longer (1.78 Å) Re–O bond length. Mn7+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with four equivalent ReO4 tetrahedra. There are two shorter (1.95 Å) and four longer (2.06 Å) Mn–O bond lengths. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Re+6.50+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Re+6.50+ and one Mn7+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Mn7+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Re+6.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(IO2)2 by Materials Project

Mn(O2I)2 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two Mn(O2I)2 ribbons oriented in the (1, 0, 1) direction. Mn4+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.89 Å) Mn–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn4+ and one I2+ atom. The O–I bond length is 2.00 Å. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn4+ and one I2+ atom. The O–I bond length is 2.03 Å. I2+ is bonded in a linear geometry to two O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(PO4)2 by Materials Project

Mn(PO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Mn(PO4)2 sheet oriented in the (1, 0, 0) direction. Mn7+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 1.75–2.10 Å. P+4.50+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of P–O bond distances ranging from 1.47–1.51 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one P+4.50+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn7+ and one P+4.50+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn7+ and one P+4.50+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Mn7+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(CuS)2 by Materials Project

Mn(CuS)2 crystallizes in the cubic F-43m space group. The structure is three-dimensional. Mn2+ is bonded in a 9-coordinate geometry to three equivalent Cu1+ and six S2- atoms. All Mn–Cu bond lengths are 2.49 Å. There are three shorter (2.60 Å) and three longer (2.82 Å) Mn–S bond lengths. There are three inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded in a 6-coordinate geometry to two equivalent Mn2+ and four S2- atoms. There are two shorter (2.33 Å) and two longer (2.44 Å) Cu–S bond lengths. In the second Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent S2- atoms. All Cu–S bond lengths are 2.37 Å. In the third Cu1+ site, Cu1+ is bonded in a tetrahedral geometry to four equivalent S2- atoms. All Cu–S bond lengths are 2.46 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms. In the second S2- site, S2- is bonded in a 7-coordinate geometry to three equivalent Mn2+ and four Cu1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(CO3)2 by Materials Project

Mn(CO3)2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is two-dimensional and consists of two Mn(CO3)2 sheets oriented in the (0, 0, 1) direction. Mn4+ is bonded to six O2- atoms to form corner-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Mn–O bond distances ranging from 1.97–2.29 Å. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. In the second C4+ site, C4+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.28 Å) C–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn4+ and one O2- atom. The O–O bond length is 1.28 Å. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Mn4+ and one C4+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Mn4+ and one C4+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C4+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Mn4+ and one C4+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Mn4+ and one O2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(IO2)2 by Materials Project

Mn(O2I)2 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two Mn(O2I)2 ribbons oriented in the (1, 0, 1) direction. Mn4+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.88 Å) and two longer (1.89 Å) Mn–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn4+ and one I2+ atom. The O–I bond length is 1.99 Å. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn4+ and one I2+ atom. The O–I bond length is 2.00 Å. I2+ is bonded in a linear geometry to two O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn(BH4)2 by Materials Project

Mn(BH4)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional and consists of two Mn(BH4)2 frameworks. Mn2+ is bonded in a 8-coordinate geometry to eight H+0.50+ atoms. There are a spread of Mn–H bond distances ranging from 2.04–2.22 Å. B3- is bonded in a tetrahedral geometry to four H+0.50+ atoms. There is two shorter (1.23 Å) and two longer (1.24 Å) B–H bond length. There are four inequivalent H+0.50+ sites. In the first H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mn2+ and one B3- atom. In the second H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mn2+ and one B3- atom. In the third H+0.50+ site, H+0.50+ is bonded in a distorted L-shaped geometry to one Mn2+ and one B3- atom. In the fourth H+0.50+ site, H+0.50+ is bonded in a distorted single-bond geometry to one Mn2+ and one B3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Observation of Topological Spin Textures in Ferrimagnetic Mn 2 − x Zn x Sb

Ferrimagnets, which have both ferromagnetic and antiferromagnetic coupling, are attracting increased attention in the realm of spintronic devices due to advantages such as ultrafast dynamics and a suppressed skyrmion Hall effect. Thus, understanding the behavior of nontrivial spin textures in ferrimagnets is crucial; however, comprehensive reports on this topic remain limited. Here, the magnetic spin textures of ferrimagnetic Mn 2 − x Zn x Sb (x = 0.85) is explored as a function of temperature and applied magnetic field. The spin textures can be tuned to a variety of states, including stripes, skyrmion bags, and a skyrmion lattice. Chiral Néel-type magnetic structures are visualized using Lorentz transmission electron microscopy. Mn(I) ions are slightly shifted toward the Sb sites, which may be due to a strong electrostatic interaction between Mn and Sb ions. This local structural distortion breaks the inversion symmetry and introduces an effective Dzyaloshinkii–Moriya interaction. This work thus provides a pathway to use doping and heterogeneity in a ferrimagnet to control and generate chiral nontrivial spin textures.

Mn ion displacement↗
DOE OSTI2023

Formation enthalpies of Al–Mn–Pd and the structure of the i-AlMnPd quasicrystal

Abstract This paper reports formation enthalpies of phases in the Al–Mn–Pd ternary alloy system as calculated from first principles using electronic density functional theory. We consider all crystal structures as reported in the assessed phase diagrams of the ternary and its binary alloy subsystems (Al–Mn, Al–Pd, and Mn–Pd), as well as additional reported or hypothetical structures. Icosahedral and decagonal quasicrystalline approximants are among the structures that we predict to be stable, or nearly so. Our results suggest the need for careful experimental reexamination of phase stability in each of the alloy systems, in tandem with further efforts to refine crystallographic and ab-initio structures.

17 WIND ENERGY↗
DOE OSTI2025

Current understanding of Oxidative Coupling of Methane (OCM) reaction over supported Mn-Na 2 WO 4 catalysts

This perspective reviews the current understanding of the Oxidative Coupling of Methane (OCM) reaction over the supported Mn-Na 2 WO 4 /SiO 2 catalyst, with a focus on recent insights gained from state-of-the-art in-situ and operando spectroscopic characterization and chemical probe experiments under controlled environments. The supported Mn-Na 2 WO 4 /SiO 2 catalyst exhibits dynamic structural changes during the OCM reaction, involving multiple reactive lattice and adsorbed oxygen species, each associated with different oxide phases. These oxygen species play distinct roles in various steps of the OCM mechanism. The catalytic active sites for activation of CH 4 are associated with isolated surface Na-WO x sites on the SiO 2 support and the role of surface MnO x sites on SiO 2 is to oxidatively dehydrogenate C 2 H 6 to C 2 H 4 . Furthermore, this paper provides a detailed discussion of these roles and also introduces new experimental data from Temporal Analysis of Products (TAP) studies to clarify the ongoing debate in the literature regarding the contributions of lattice versus adsorbed oxygen species in OCM reaction product formation. Additionally, recommendations are offered for optimizing the performance of supported Mn-Na 2 WO 4 /SiO 2 catalysts to enhance CH 4 activation and C 2 product selectivity.

03 - NATURAL GAS↗
DOE OSTI2021

Effects of Co doping on the structure and physicochemical properties of hausmannite (Mn 3 O 4 ) and its transformation during aging

Hausmannite is a common low-valence manganese oxide mineral with a distorted spinel structure in surficial sediments. Although natural Mn oxides often contain various transition metal (TM) impurities, few studies have addressed the substitution mechanisms of TMs, such as cobalt (Co), with hausmannite and induced changes in the mineral physicochemical properties. In this study, Co-doped hausmannites with final Co/Mn molar ratios of 0.05 and 0.11 were synthesized and characterized by wet chemical analysis, powder X-ray diffraction (XRD), Fourier transformed infrared spectra (FTIR), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure spectroscopy (XAFS). Co-doped samples have larger crystallite sizes and smaller specific surface areas than those of the hausmannite without Co. The Co cations exist in a mixed-valence of +3 and + 2. Powder XRD and acid dissolution experiments indicate that Co incorporates into the mineral structures, and increases the mineral structural stability. Co K-edge extended X-ray adsorption fine structure (EXAFS) analysis demonstrates that Co likely substitutes for lattice Mn(III). After aging at room temperature for three years, 14.1 ± 1.9% of pure hausmannite is transformed to manganite while only 2.6 ± 0.7% of manganite appears in the aged Co-doped sample with an initial Co/Mn molar ratio of 0.10. Finally, these results provide new insights into the incorporation mechanisms of TMs into low valence Mn oxides, and the stability of these minerals in natural environments.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗