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At least 397 records · Page 22
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DOE OSTI2020

Materials Data on Al4Fe5Rh by Materials Project

Fe5RhAl4 is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a body-centered cubic geometry to four equivalent Rh and four equivalent Al atoms. All Fe–Rh bond lengths are 2.59 Å. All Fe–Al bond lengths are 2.56 Å. In the second Fe site, Fe is bonded in a body-centered cubic geometry to eight Al atoms. All Fe–Al bond lengths are 2.46 Å. In the third Fe site, Fe is bonded in a body-centered cubic geometry to eight equivalent Al atoms. All Fe–Al bond lengths are 2.52 Å. Rh is bonded in a body-centered cubic geometry to eight equivalent Fe atoms. There are two inequivalent Al sites. In the first Al site, Al is bonded in a body-centered cubic geometry to eight Fe atoms. In the second Al site, Al is bonded in a body-centered cubic geometry to eight Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr5Co4Ni by Materials Project

Zr5Co4Ni is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Zr sites. In the first Zr site, Zr is bonded in a body-centered cubic geometry to four equivalent Co and four equivalent Ni atoms. All Zr–Co bond lengths are 2.79 Å. All Zr–Ni bond lengths are 2.79 Å. In the second Zr site, Zr is bonded in a body-centered cubic geometry to eight Co atoms. There are four shorter (2.78 Å) and four longer (2.79 Å) Zr–Co bond lengths. In the third Zr site, Zr is bonded in a body-centered cubic geometry to eight equivalent Co atoms. All Zr–Co bond lengths are 2.78 Å. There are two inequivalent Co sites. In the first Co site, Co is bonded in a body-centered cubic geometry to eight Zr atoms. In the second Co site, Co is bonded in a body-centered cubic geometry to eight Zr atoms. Ni is bonded in a body-centered cubic geometry to eight equivalent Zr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnV(Ni2Sn)2 by Materials Project

VMn(Ni2Sn)2 is Tungsten-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. V is bonded in a distorted body-centered cubic geometry to eight Ni and six equivalent Sn atoms. There are two shorter (2.62 Å) and six longer (2.63 Å) V–Ni bond lengths. All V–Sn bond lengths are 3.03 Å. Mn is bonded in a distorted body-centered cubic geometry to eight Ni and six equivalent Sn atoms. All Mn–Ni bond lengths are 2.63 Å. All Mn–Sn bond lengths are 3.04 Å. There are four inequivalent Ni sites. In the first Ni site, Ni is bonded in a distorted body-centered cubic geometry to one V, three equivalent Mn, and four equivalent Sn atoms. All Ni–Sn bond lengths are 2.63 Å. In the second Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. In the third Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. All Ni–V bond lengths are 2.63 Å. The Ni–Mn bond length is 2.63 Å. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. In the fourth Ni site, Ni is bonded in a distorted body-centered cubic geometry to three equivalent V, one Mn, and four equivalent Sn atoms. All Ni–V bond lengths are 2.63 Å. There are one shorter (2.62 Å) and three longer (2.63 Å) Ni–Sn bond lengths. Sn is bonded in a 8-coordinate geometry to three equivalent V, three equivalent Mn, and eight Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn2InSbPd4 by Materials Project

Mn2Pd4InSb is Heusler-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Mn is bonded in a body-centered cubic geometry to eight Pd and three equivalent Sb atoms. There are a spread of Mn–Pd bond distances ranging from 2.76–2.82 Å. All Mn–Sb bond lengths are 3.24 Å. There are three inequivalent Pd sites. In the first Pd site, Pd is bonded in a body-centered cubic geometry to four equivalent Mn, three equivalent In, and one Sb atom. All Pd–In bond lengths are 2.79 Å. The Pd–Sb bond length is 2.78 Å. In the second Pd site, Pd is bonded in a body-centered cubic geometry to four equivalent Mn, one In, and three equivalent Sb atoms. The Pd–In bond length is 2.79 Å. All Pd–Sb bond lengths are 2.79 Å. In the third Pd site, Pd is bonded in a body-centered cubic geometry to four equivalent Mn, three equivalent In, and one Sb atom. All Pd–In bond lengths are 2.79 Å. The Pd–Sb bond length is 2.78 Å. In is bonded in a body-centered cubic geometry to eight Pd atoms. Sb is bonded in a distorted body-centered cubic geometry to six equivalent Mn and eight Pd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgSc5Al4 by Materials Project

MgSc5Al4 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Mg is bonded in a distorted body-centered cubic geometry to eight equivalent Sc atoms. All Mg–Sc bond lengths are 3.05 Å. There are three inequivalent Sc sites. In the first Sc site, Sc is bonded in a distorted body-centered cubic geometry to four equivalent Mg and four equivalent Al atoms. All Sc–Al bond lengths are 2.91 Å. In the second Sc site, Sc is bonded in a body-centered cubic geometry to eight Al atoms. There are four shorter (2.93 Å) and four longer (2.96 Å) Sc–Al bond lengths. In the third Sc site, Sc is bonded in a body-centered cubic geometry to eight equivalent Al atoms. All Sc–Al bond lengths are 2.94 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a body-centered cubic geometry to eight Sc atoms. In the second Al site, Al is bonded in a body-centered cubic geometry to eight Sc atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nd5MgAl4 by Materials Project

MgNd5Al4 is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Mg is bonded in a body-centered cubic geometry to eight equivalent Nd atoms. All Mg–Nd bond lengths are 3.35 Å. There are three inequivalent Nd sites. In the first Nd site, Nd is bonded in a distorted body-centered cubic geometry to four equivalent Mg and four equivalent Al atoms. All Nd–Al bond lengths are 3.19 Å. In the second Nd site, Nd is bonded in a body-centered cubic geometry to eight Al atoms. There are four shorter (3.22 Å) and four longer (3.27 Å) Nd–Al bond lengths. In the third Nd site, Nd is bonded in a body-centered cubic geometry to eight equivalent Al atoms. All Nd–Al bond lengths are 3.23 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded in a body-centered cubic geometry to eight Nd atoms. In the second Al site, Al is bonded in a body-centered cubic geometry to eight Nd atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg64Si32Bi by Materials Project

Mg64Si32Bi crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to four Si atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. There are one shorter (2.72 Å) and three longer (2.76 Å) Mg–Si bond lengths. In the second Mg site, Mg is bonded to four Si atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.74–2.81 Å. In the third Mg site, Mg is bonded to four Si atoms to form a mixture of edge and corner-sharing MgSi4 tetrahedra. There are a spread of Mg–Si bond distances ranging from 2.74–2.78 Å. In the fourth Mg site, Mg is bonded in a 5-coordinate geometry to four Si and one Bi atom. There are one shorter (2.60 Å) and three longer (2.82 Å) Mg–Si bond lengths. The Mg–Bi bond length is 2.97 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded in a body-centered cubic geometry to eight Mg atoms. In the second Si site, Si is bonded in a distorted body-centered cubic geometry to eight Mg atoms. In the third Si site, Si is bonded in a body-centered cubic geometry to eight Mg atoms. In the fourth Si site, Si is bonded in a body-centered cubic geometry to eight Mg atoms. Bi is bonded in a distorted body-centered cubic geometry to eight equivalent Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tl5BrCl4 by Materials Project

Tl5BrCl4 is Heusler-like structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are three inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a body-centered cubic geometry to eight Cl1- atoms. There are four shorter (3.40 Å) and four longer (3.41 Å) Tl–Cl bond lengths. In the second Tl1+ site, Tl1+ is bonded in a body-centered cubic geometry to two equivalent Br1- and six Cl1- atoms. Both Tl–Br bond lengths are 3.45 Å. There are two shorter (3.37 Å) and four longer (3.41 Å) Tl–Cl bond lengths. In the third Tl1+ site, Tl1+ is bonded in a body-centered cubic geometry to four equivalent Br1- and four equivalent Cl1- atoms. All Tl–Br bond lengths are 3.41 Å. All Tl–Cl bond lengths are 3.42 Å. Br1- is bonded in a body-centered cubic geometry to eight Tl1+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a body-centered cubic geometry to eight Tl1+ atoms. In the second Cl1- site, Cl1- is bonded in a body-centered cubic geometry to eight Tl1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li22Ge5 by Materials Project

Li22Ge5 crystallizes in the cubic F-43m space group. The structure is three-dimensional. there are sixteen inequivalent Li sites. In the first Li site, Li is bonded in a body-centered cubic geometry to four equivalent Li and four equivalent Ge atoms. All Li–Li bond lengths are 2.47 Å. All Li–Ge bond lengths are 2.89 Å. In the second Li site, Li is bonded in a body-centered cubic geometry to eight Li atoms. There are four shorter (2.54 Å) and four longer (2.72 Å) Li–Li bond lengths. In the third Li site, Li is bonded in a body-centered cubic geometry to eight Li atoms. There are four shorter (2.54 Å) and four longer (2.66 Å) Li–Li bond lengths. In the fourth Li site, Li is bonded in a distorted body-centered cubic geometry to four equivalent Li and four equivalent Ge atoms. All Li–Li bond lengths are 2.58 Å. All Li–Ge bond lengths are 2.73 Å. In the fifth Li site, Li is bonded in a 11-coordinate geometry to eight Li and three equivalent Ge atoms. There are a spread of Li–Li bond distances ranging from 2.66–3.04 Å. All Li–Ge bond lengths are 3.11 Å. In the sixth Li site, Li is bonded in a 2-coordinate geometry to three Ge atoms. There are two shorter (2.70 Å) and one longer (3.02 Å) Li–Ge bond lengths. In the seventh Li site, Li is bonded in a distorted single-bond geometry to three Ge atoms. There are one shorter (2.70 Å) and two longer (3.07 Å) Li–Ge bond lengths. In the eighth Li site, Li is bonded in a 3-coordinate geometry to two Li and three equivalent Ge atoms. All Li–Ge bond lengths are 2.81 Å. In the ninth Li site, Li is bonded in a distorted linear geometry to one Li and two Ge atoms. There are one shorter (2.65 Å) and one longer (2.66 Å) Li–Ge bond lengths. In the tenth Li site, Li is bonded in a 3-coordinate geometry to one Li and three equivalent Ge atoms. All Li–Ge bond lengths are 2.78 Å. In the eleventh Li site, Li is bonded in a distorted bent 120 degrees geometry to two Ge atoms. There are one shorter (2.65 Å) and one longer (2.67 Å) Li–Ge bond lengths. In the twelfth Li site, Li is bonded in a 3-coordinate geometry to one Li and three equivalent Ge atoms. All Li–Ge bond lengths are 2.77 Å. In the thirteenth Li site, Li is bonded in a 4-coordinate geometry to one Li and four Ge atoms. There are one shorter (2.72 Å) and three longer (2.82 Å) Li–Ge bond lengths. In the fourteenth Li site, Li is bonded in a distorted single-bond geometry to three Ge atoms. There are one shorter (2.76 Å) and two longer (3.08 Å) Li–Ge bond lengths. In the fifteenth Li site, Li is bonded in a distorted single-bond geometry to one Li and one Ge atom. The Li–Ge bond length is 2.70 Å. In the sixteenth Li site, Li is bonded in a 2-coordinate geometry to two equivalent Li and three Ge atoms. There are two shorter (2.79 Å) and one longer (2.96 Å) Li–Ge bond lengths. There are four inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to eleven Li atoms. In the second Ge site, Ge is bonded in a distorted body-centered cubic geometry to eight Li atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to thirteen Li atoms. In the fourth Ge site, Ge is bonded in a 8-coordinate geometry to thirteen Li atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zn4Ni5Ge by Materials Project

Ni5Zn4Ge is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are three inequivalent Ni sites. In the first Ni site, Ni is bonded in a body-centered cubic geometry to four equivalent Zn and four equivalent Ge atoms. All Ni–Zn bond lengths are 2.56 Å. All Ni–Ge bond lengths are 2.49 Å. In the second Ni site, Ni is bonded in a body-centered cubic geometry to eight Zn atoms. There are four shorter (2.50 Å) and four longer (2.51 Å) Ni–Zn bond lengths. In the third Ni site, Ni is bonded in a body-centered cubic geometry to eight equivalent Zn atoms. All Ni–Zn bond lengths are 2.51 Å. There are two inequivalent Zn sites. In the first Zn site, Zn is bonded in a distorted body-centered cubic geometry to eight Ni atoms. In the second Zn site, Zn is bonded in a body-centered cubic geometry to eight Ni atoms. Ge is bonded in a distorted body-centered cubic geometry to eight equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrFe11Si4 by Materials Project

Fe11CrSi4 is Tungsten-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Cr is bonded in a distorted body-centered cubic geometry to eight Fe atoms. There are two shorter (2.39 Å) and six longer (2.41 Å) Cr–Fe bond lengths. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded in a distorted body-centered cubic geometry to four Fe and four Si atoms. There are three shorter (2.41 Å) and one longer (2.43 Å) Fe–Fe bond lengths. There are one shorter (2.40 Å) and three longer (2.42 Å) Fe–Si bond lengths. In the second Fe site, Fe is bonded in a distorted body-centered cubic geometry to four Fe and four equivalent Si atoms. There are one shorter (2.40 Å) and three longer (2.42 Å) Fe–Fe bond lengths. All Fe–Si bond lengths are 2.42 Å. In the third Fe site, Fe is bonded in a distorted body-centered cubic geometry to one Cr, three equivalent Fe, and four Si atoms. All Fe–Fe bond lengths are 2.44 Å. There are three shorter (2.40 Å) and one longer (2.47 Å) Fe–Si bond lengths. In the fourth Fe site, Fe is bonded in a 8-coordinate geometry to three equivalent Cr, one Fe, and four equivalent Si atoms. The Fe–Fe bond length is 2.48 Å. There are one shorter (2.40 Å) and three longer (2.43 Å) Fe–Si bond lengths. In the fifth Fe site, Fe is bonded in a 8-coordinate geometry to eight Fe and six Si atoms. There are three shorter (2.79 Å) and three longer (2.80 Å) Fe–Si bond lengths. In the sixth Fe site, Fe is bonded in a 8-coordinate geometry to eight Fe and six equivalent Si atoms. All Fe–Si bond lengths are 2.79 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded in a distorted body-centered cubic geometry to fourteen Fe atoms. In the second Si site, Si is bonded in a distorted body-centered cubic geometry to eleven Fe atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al2CrFeCo4 by Materials Project

CrFeCo4Al2 is Tungsten-derived structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Cr is bonded in a body-centered cubic geometry to eight Co atoms. All Cr–Co bond lengths are 2.47 Å. Fe is bonded in a distorted body-centered cubic geometry to eight Co and six equivalent Al atoms. There are two shorter (2.46 Å) and six longer (2.47 Å) Fe–Co bond lengths. All Fe–Al bond lengths are 2.85 Å. There are three inequivalent Co sites. In the first Co site, Co is bonded in a body-centered cubic geometry to three equivalent Cr, one Fe, and four equivalent Al atoms. All Co–Al bond lengths are 2.46 Å. In the second Co site, Co is bonded in a body-centered cubic geometry to one Cr, three equivalent Fe, and four equivalent Al atoms. All Co–Al bond lengths are 2.47 Å. In the third Co site, Co is bonded in a body-centered cubic geometry to three equivalent Cr, one Fe, and four equivalent Al atoms. All Co–Cr bond lengths are 2.47 Å. The Co–Fe bond length is 2.46 Å. All Co–Al bond lengths are 2.46 Å. Al is bonded in a body-centered cubic geometry to three equivalent Fe and eight Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZrU4O10 by Materials Project

U4ZrO10 is Fluorite-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent U4+ sites. In the first U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.32 Å) and six longer (2.34 Å) U–O bond lengths. In the second U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.34–2.36 Å. In the third U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are five shorter (2.34 Å) and three longer (2.35 Å) U–O bond lengths. In the fourth U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.30–2.36 Å. In the fifth U4+ site, U4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.32–2.37 Å. Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.25–2.30 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to four U4+ atoms to form OU4 tetrahedra that share corners with sixteen OU4 tetrahedra and edges with six OZrU3 tetrahedra. In the second O2- site, O2- is bonded to four U4+ atoms to form OU4 tetrahedra that share corners with sixteen OU4 tetrahedra and edges with six OZrU3 tetrahedra. In the third O2- site, O2- is bonded to three U4+ and one Zr4+ atom to form OZrU3 tetrahedra that share corners with sixteen OZrU3 tetrahedra and edges with six OU4 tetrahedra. In the fourth O2- site, O2- is bonded to two U4+ and two equivalent Zr4+ atoms to form OZr2U2 tetrahedra that share corners with sixteen OU4 tetrahedra and edges with six OZrU3 tetrahedra. In the fifth O2- site, O2- is bonded to three U4+ and one Zr4+ atom to form OZrU3 tetrahedra that share corners with sixteen OU4 tetrahedra and edges with six OZrU3 tetrahedra. In the sixth O2- site, O2- is bonded to three U4+ and one Zr4+ atom to form a mixture of corner and edge-sharing OZrU3 tetrahedra. In the seventh O2- site, O2- is bonded to four U4+ atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the eighth O2- site, O2- is bonded to three U4+ and one Zr4+ atom to form OZrU3 tetrahedra that share corners with sixteen OU4 tetrahedra and edges with six OZrU3 tetrahedra. In the ninth O2- site, O2- is bonded to four U4+ atoms to form a mixture of corner and edge-sharing OU4 tetrahedra. In the tenth O2- site, O2- is bonded to two U4+ and two equivalent Zr4+ atoms to form a mixture of corner and edge-sharing OZr2U2 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg4CdAg5 by Materials Project

Mg4Ag5Cd is Heusler-like structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a body-centered cubic geometry to eight Ag atoms. There are four shorter (2.87 Å) and four longer (2.90 Å) Mg–Ag bond lengths. In the second Mg site, Mg is bonded in a body-centered cubic geometry to eight Ag atoms. There are four shorter (2.90 Å) and four longer (2.91 Å) Mg–Ag bond lengths. There are three inequivalent Ag sites. In the first Ag site, Ag is bonded in a body-centered cubic geometry to four equivalent Mg and four equivalent Cd atoms. All Ag–Cd bond lengths are 2.94 Å. In the second Ag site, Ag is bonded in a body-centered cubic geometry to eight Mg atoms. In the third Ag site, Ag is bonded in a body-centered cubic geometry to eight equivalent Mg atoms. Cd is bonded in a body-centered cubic geometry to eight equivalent Ag atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg13(NbH16)2 by Materials Project

Mg13(NbH16)2 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a body-centered cubic geometry to eight H+0.94- atoms. There are four shorter (2.04 Å) and four longer (2.08 Å) Mg–H bond lengths. In the second Mg2+ site, Mg2+ is bonded in a body-centered cubic geometry to eight H+0.94- atoms. There are four shorter (1.97 Å) and four longer (2.11 Å) Mg–H bond lengths. In the third Mg2+ site, Mg2+ is bonded in a body-centered cubic geometry to eight H+0.94- atoms. There are a spread of Mg–H bond distances ranging from 1.94–2.10 Å. In the fourth Mg2+ site, Mg2+ is bonded in a body-centered cubic geometry to eight equivalent H+0.94- atoms. All Mg–H bond lengths are 2.12 Å. There are two inequivalent Nb2+ sites. In the first Nb2+ site, Nb2+ is bonded in a body-centered cubic geometry to eight equivalent H+0.94- atoms. All Nb–H bond lengths are 1.93 Å. In the second Nb2+ site, Nb2+ is bonded in a body-centered cubic geometry to eight equivalent H+0.94- atoms. All Nb–H bond lengths are 1.94 Å. There are four inequivalent H+0.94- sites. In the first H+0.94- site, H+0.94- is bonded to three Mg2+ and one Nb2+ atom to form a mixture of edge and corner-sharing HMg3Nb tetrahedra. In the second H+0.94- site, H+0.94- is bonded to four Mg2+ atoms to form a mixture of edge and corner-sharing HMg4 tetrahedra. In the third H+0.94- site, H+0.94- is bonded in a trigonal planar geometry to three Mg2+ atoms. In the fourth H+0.94- site, H+0.94- is bonded to three Mg2+ and one Nb2+ atom to form HMg3Nb tetrahedra that share corners with twelve HMg3Nb tetrahedra and edges with four HMg4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2021

A fourth-order Lagrangian discontinuous Galerkin method using a hierarchical orthogonal basis on curvilinear grids

The existing high-order Lagrangian discontinuous Galerkin (DG) hydrodynamic methods are restricted to using quadratic meshes with quadratic polynomials (P2), which in turn, yield up to third-order accuracy. Additionally, these existing DG hydrodynamic schemes, when extended to work with cubic meshes and cubic polynomials (P3), can be unstable on strong-shock problems. Therefore, this paper presents a new Lagrangian discontinuous Galerkin (DG) hydrodynamic method to simulate compressible material dynamics ( e.g., gasses, fluids, and solids) with strong-shocks using cubic meshes and cubic polynomials, and delivers up to fourth-order accuracy on smooth flows. The stability on shock problems is achieved using new hierarchical orthogonal basis functions and a new subcell mesh stabilization (SMS) scheme for cubic meshes. The accuracy and robustness of the new high-order accurate Lagrangian DG hydrodynamic method is demonstrated by simulating a diverse suite of challenging test problems covering gas and solid dynamic problems on curvilinear meshes.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

Characterization and interaction of geometric and contact/impact nonlinearities in dynamical systems

Here, we study how a contact/impact nonlinearity interacts with a geometric cubic nonlinearity in an oscillator system. Specific focus is shown to the effects on bifurcation behavior and secondary resonances (i.e., super- and sub-harmonic resonances). The effects of the individual nonlinearities are first explored for comparison, and then the influences of the combined nonlinearities, varying one parameter at a time, are analyzed and discussed. Nonlinear characterization is then performed on an arbitrary system configuration to study super- and sub-harmonic resonances and grazing contacts or bifurcations. Both the cubic and contact nonlinearities cause a drop in amplitude and shift up in frequency for the primary resonance, and they activate high-amplitude subharmonic resonance regions. The nonlinearities seem to never destructively interfere. The contact nonlinearity generally affects the system’s superharmonic resonance behavior more, particularly with regard to the occurrence of grazing contacts and the activation of many bifurcations in the system’s response. The subharmonic resonance behavior is more strongly affected by the cubic nonlinearity and is prone to multistable behavior. Perturbation theory proved useful for determining when the cubic nonlinearity would be dominant compared to the contact nonlinearity. The limiting behaviors of the contact stiffness and freeplay gap size indicate the cubic nonlinearity is dominant overall. It is demonstrated that the presence of contact may result in the activation of several bifurcations. In addition, it is proved that the system’s subharmonic resonance region is prone to multistable dynamical responses having distinct magnitudes.

42 ENGINEERING↗