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DOE OSTI2020

Materials Data on ReOs by Materials Project

ReOs crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Re is bonded to six equivalent Re and six equivalent Os atoms to form distorted ReRe6Os6 cuboctahedra that share corners with eighteen equivalent ReRe6Os6 cuboctahedra, edges with six equivalent ReRe6Os6 cuboctahedra, edges with twelve equivalent OsRe6Os6 cuboctahedra, faces with eight equivalent ReRe6Os6 cuboctahedra, and faces with twelve equivalent OsRe6Os6 cuboctahedra. All Re–Re bond lengths are 2.78 Å. All Re–Os bond lengths are 2.72 Å. Os is bonded to six equivalent Re and six equivalent Os atoms to form distorted OsRe6Os6 cuboctahedra that share corners with eighteen equivalent OsRe6Os6 cuboctahedra, edges with six equivalent OsRe6Os6 cuboctahedra, edges with twelve equivalent ReRe6Os6 cuboctahedra, faces with eight equivalent OsRe6Os6 cuboctahedra, and faces with twelve equivalent ReRe6Os6 cuboctahedra. All Os–Os bond lengths are 2.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re2Mo3C by Materials Project

Mo3Re2C crystallizes in the cubic P4_132 space group. The structure is three-dimensional. Mo is bonded in a distorted bent 150 degrees geometry to six equivalent Re and two equivalent C atoms. There are a spread of Mo–Re bond distances ranging from 2.85–2.96 Å. Both Mo–C bond lengths are 2.17 Å. Re is bonded to nine equivalent Mo and three equivalent Re atoms to form ReRe3Mo9 cuboctahedra that share corners with fifteen equivalent ReRe3Mo9 cuboctahedra, edges with three equivalent CMo6 octahedra, faces with ten equivalent ReRe3Mo9 cuboctahedra, and faces with four equivalent CMo6 octahedra. All Re–Re bond lengths are 2.59 Å. C is bonded to six equivalent Mo atoms to form distorted CMo6 octahedra that share corners with six equivalent CMo6 octahedra, edges with six equivalent ReRe3Mo9 cuboctahedra, and faces with eight equivalent ReRe3Mo9 cuboctahedra. The corner-sharing octahedral tilt angles are 23°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TiReSi by Materials Project

TiReSi crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Ti is bonded in a 11-coordinate geometry to six equivalent Re and five Si atoms. There are two shorter (2.79 Å) and four longer (2.92 Å) Ti–Re bond lengths. There are four shorter (2.64 Å) and one longer (2.76 Å) Ti–Si bond lengths. Re is bonded in a 10-coordinate geometry to six equivalent Ti and four Si atoms. There are two shorter (2.42 Å) and two longer (2.55 Å) Re–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to three equivalent Ti and six equivalent Re atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to six equivalent Ti and three equivalent Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Br8Cl by Materials Project

Re3Br8Cl crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of one Re3Br8Cl sheet oriented in the (2, 0, -1) direction. there are four inequivalent Re3+ sites. In the first Re3+ site, Re3+ is bonded to five Br1- atoms to form distorted ReBr5 square pyramids that share corners with two ReBr5 square pyramids and an edgeedge with one ReBr4Cl square pyramid. There are a spread of Re–Br bond distances ranging from 2.43–2.86 Å. In the second Re3+ site, Re3+ is bonded to four Br1- and one Cl1- atom to form distorted ReBr4Cl square pyramids that share corners with two ReBr4Cl square pyramids and an edgeedge with one ReBr5 square pyramid. There are a spread of Re–Br bond distances ranging from 2.43–2.85 Å. The Re–Cl bond length is 2.43 Å. In the third Re3+ site, Re3+ is bonded to five Br1- atoms to form distorted ReBr5 square pyramids that share corners with two equivalent ReBr5 square pyramids and an edgeedge with one ReBr3Cl2 square pyramid. There are a spread of Re–Br bond distances ranging from 2.43–2.85 Å. In the fourth Re3+ site, Re3+ is bonded to three Br1- and two equivalent Cl1- atoms to form distorted ReBr3Cl2 square pyramids that share corners with two equivalent ReBr4Cl square pyramids and an edgeedge with one ReBr5 square pyramid. There are a spread of Re–Br bond distances ranging from 2.43–2.85 Å. Both Re–Cl bond lengths are 2.43 Å. There are eleven inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Re3+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Re3+ atom. In the third Br1- site, Br1- is bonded in a water-like geometry to two Re3+ atoms. In the fourth Br1- site, Br1- is bonded in a water-like geometry to two Re3+ atoms. In the fifth Br1- site, Br1- is bonded in a 12-coordinate geometry to two equivalent Re3+ atoms. In the sixth Br1- site, Br1- is bonded in a 12-coordinate geometry to two equivalent Re3+ atoms. In the seventh Br1- site, Br1- is bonded in a single-bond geometry to one Re3+ atom. In the eighth Br1- site, Br1- is bonded in a single-bond geometry to one Re3+ atom. In the ninth Br1- site, Br1- is bonded in a water-like geometry to two Re3+ atoms. In the tenth Br1- site, Br1- is bonded in a water-like geometry to two Re3+ atoms. In the eleventh Br1- site, Br1- is bonded in a 12-coordinate geometry to two Re3+ atoms. Cl1- is bonded in a 12-coordinate geometry to two Re3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnRe by Materials Project

ReZn crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Re is bonded to six equivalent Re and six equivalent Zn atoms to form ReZn6Re6 cuboctahedra that share corners with eighteen equivalent ReZn6Re6 cuboctahedra, edges with six equivalent ReZn6Re6 cuboctahedra, edges with twelve equivalent ZnZn6Re6 cuboctahedra, faces with eight equivalent ReZn6Re6 cuboctahedra, and faces with twelve equivalent ZnZn6Re6 cuboctahedra. All Re–Re bond lengths are 2.75 Å. All Re–Zn bond lengths are 2.75 Å. Zn is bonded to six equivalent Re and six equivalent Zn atoms to form ZnZn6Re6 cuboctahedra that share corners with eighteen equivalent ZnZn6Re6 cuboctahedra, edges with six equivalent ZnZn6Re6 cuboctahedra, edges with twelve equivalent ReZn6Re6 cuboctahedra, faces with eight equivalent ZnZn6Re6 cuboctahedra, and faces with twelve equivalent ReZn6Re6 cuboctahedra. All Zn–Zn bond lengths are 2.75 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ReH(CO)4 by Materials Project

ReH(CO)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two ReH(CO)4 clusters. there are three inequivalent Re7+ sites. In the first Re7+ site, Re7+ is bonded to four C and two H1+ atoms to form corner-sharing ReH2C4 octahedra. The corner-sharing octahedra tilt angles range from 49–50°. There is two shorter (1.94 Å) and two longer (2.00 Å) Re–C bond length. There is one shorter (1.87 Å) and one longer (1.89 Å) Re–H bond length. In the second Re7+ site, Re7+ is bonded to four C and two H1+ atoms to form corner-sharing ReH2C4 octahedra. The corner-sharing octahedral tilt angles are 50°. There are a spread of Re–C bond distances ranging from 1.94–2.01 Å. There is one shorter (1.88 Å) and one longer (1.89 Å) Re–H bond length. In the third Re7+ site, Re7+ is bonded to four C and two H1+ atoms to form corner-sharing ReH2C4 octahedra. The corner-sharing octahedra tilt angles range from 49–50°. There are a spread of Re–C bond distances ranging from 1.94–2.01 Å. There is one shorter (1.88 Å) and one longer (1.89 Å) Re–H bond length. There are twelve inequivalent C sites. In the first C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.17 Å. In the second C site, C is bonded in a distorted linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C site, C is bonded in a distorted linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C site, C is bonded in a distorted linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.15 Å. In the seventh C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.17 Å. In the ninth C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the tenth C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the eleventh C site, C is bonded in a linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.16 Å. In the twelfth C site, C is bonded in a distorted linear geometry to one Re7+ and one O2- atom. The C–O bond length is 1.15 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a bent 120 degrees geometry to two Re7+ atoms. In the second H1+ site, H1+ is bonded in a bent 120 degrees geometry to two Re7+ atoms. In the third H1+ site, H1+ is bonded in a bent 120 degrees geometry to two Re7+ atoms. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one C atom. In the twelfth O2- site, O2- is bonded in a single-bond geometry to one C atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NbReSi by Materials Project

NbReSi crystallizes in the hexagonal P-62m space group. The structure is three-dimensional. Nb is bonded in a 11-coordinate geometry to six equivalent Re and five Si atoms. There are two shorter (2.87 Å) and four longer (2.95 Å) Nb–Re bond lengths. There are four shorter (2.68 Å) and one longer (2.78 Å) Nb–Si bond lengths. Re is bonded in a 10-coordinate geometry to six equivalent Nb and four Si atoms. There are two shorter (2.43 Å) and two longer (2.60 Å) Re–Si bond lengths. There are two inequivalent Si sites. In the first Si site, Si is bonded in a 9-coordinate geometry to three equivalent Nb and six equivalent Re atoms. In the second Si site, Si is bonded in a 9-coordinate geometry to six equivalent Nb and three equivalent Re atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CoRe by Materials Project

CoRe is Magnesium-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Re is bonded to six equivalent Re and six equivalent Co atoms to form ReCo6Re6 cuboctahedra that share corners with eighteen equivalent ReCo6Re6 cuboctahedra, edges with six equivalent ReCo6Re6 cuboctahedra, edges with twelve equivalent CoCo6Re6 cuboctahedra, faces with eight equivalent ReCo6Re6 cuboctahedra, and faces with twelve equivalent CoCo6Re6 cuboctahedra. All Re–Re bond lengths are 2.68 Å. All Re–Co bond lengths are 2.59 Å. Co is bonded to six equivalent Re and six equivalent Co atoms to form CoCo6Re6 cuboctahedra that share corners with eighteen equivalent CoCo6Re6 cuboctahedra, edges with six equivalent CoCo6Re6 cuboctahedra, edges with twelve equivalent ReCo6Re6 cuboctahedra, faces with eight equivalent CoCo6Re6 cuboctahedra, and faces with twelve equivalent ReCo6Re6 cuboctahedra. All Co–Co bond lengths are 2.68 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaEu(ReO5)4 by Materials Project

NaEu(ReO5)4 crystallizes in the tetragonal P-4n2 space group. The structure is three-dimensional. Na is bonded in a 8-coordinate geometry to eight O atoms. There are four shorter (2.57 Å) and four longer (2.69 Å) Na–O bond lengths. Eu is bonded in a 8-coordinate geometry to eight O atoms. There are four shorter (2.36 Å) and four longer (2.39 Å) Eu–O bond lengths. Re is bonded in a tetrahedral geometry to four O atoms. There is three shorter (1.74 Å) and one longer (1.80 Å) Re–O bond length. There are five inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Re atom. In the second O site, O is bonded in a distorted single-bond geometry to one Na and one Re atom. In the third O site, O is bonded in a single-bond geometry to one Eu atom. In the fourth O site, O is bonded in a distorted bent 150 degrees geometry to one Na and one Re atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Eu and one Re atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GaRe by Materials Project

ReGa crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Re is bonded to six equivalent Re and six equivalent Ga atoms to form distorted ReGa6Re6 cuboctahedra that share corners with eighteen equivalent ReGa6Re6 cuboctahedra, edges with six equivalent ReGa6Re6 cuboctahedra, edges with twelve equivalent GaGa6Re6 cuboctahedra, faces with eight equivalent ReGa6Re6 cuboctahedra, and faces with twelve equivalent GaGa6Re6 cuboctahedra. All Re–Re bond lengths are 2.89 Å. All Re–Ga bond lengths are 2.65 Å. Ga is bonded to six equivalent Re and six equivalent Ga atoms to form distorted GaGa6Re6 cuboctahedra that share corners with eighteen equivalent GaGa6Re6 cuboctahedra, edges with six equivalent GaGa6Re6 cuboctahedra, edges with twelve equivalent ReGa6Re6 cuboctahedra, faces with eight equivalent GaGa6Re6 cuboctahedra, and faces with twelve equivalent ReGa6Re6 cuboctahedra. All Ga–Ga bond lengths are 2.89 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TlRe by Materials Project

ReTl crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Re is bonded in a 10-coordinate geometry to two equivalent Re and eight equivalent Tl atoms. Both Re–Re bond lengths are 2.48 Å. There are a spread of Re–Tl bond distances ranging from 3.05–3.15 Å. Tl is bonded to eight equivalent Re and four equivalent Tl atoms to form a mixture of distorted edge, face, and corner-sharing TlTl4Re8 cuboctahedra. There are two shorter (3.04 Å) and two longer (3.10 Å) Tl–Tl bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrRe3 by Materials Project

CrRe3 is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Cr is bonded to twelve equivalent Re atoms to form CrRe12 cuboctahedra that share corners with twelve equivalent CrRe12 cuboctahedra, edges with twenty-four equivalent ReCr4Re8 cuboctahedra, faces with six equivalent CrRe12 cuboctahedra, and faces with twelve equivalent ReCr4Re8 cuboctahedra. All Cr–Re bond lengths are 2.73 Å. Re is bonded to four equivalent Cr and eight equivalent Re atoms to form ReCr4Re8 cuboctahedra that share corners with twelve equivalent ReCr4Re8 cuboctahedra, edges with eight equivalent CrRe12 cuboctahedra, edges with sixteen equivalent ReCr4Re8 cuboctahedra, faces with four equivalent CrRe12 cuboctahedra, and faces with fourteen equivalent ReCr4Re8 cuboctahedra. All Re–Re bond lengths are 2.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K4Re2HCl10O by Materials Project

(K4Re2OCl10)2H2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of two hydrogen molecules and one K4Re2OCl10 framework. In the K4Re2OCl10 framework, there are two inequivalent K1+ sites. In the first K1+ site, K1+ is bonded to twelve Cl1- atoms to form KCl12 cuboctahedra that share corners with four equivalent KCl12 cuboctahedra, faces with four equivalent KCl12 cuboctahedra, and faces with four equivalent ReCl5O octahedra. There are eight shorter (3.58 Å) and four longer (3.63 Å) K–Cl bond lengths. In the second K1+ site, K1+ is bonded in a body-centered cubic geometry to eight equivalent Cl1- atoms. All K–Cl bond lengths are 3.26 Å. Re+3.50+ is bonded to one O2- and five Cl1- atoms to form ReCl5O octahedra that share a cornercorner with one ReCl5O octahedra and faces with four equivalent KCl12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. The Re–O bond length is 1.86 Å. All Re–Cl bond lengths are 2.41 Å. O2- is bonded in a linear geometry to two equivalent Re+3.50+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to four equivalent K1+ and one Re+3.50+ atom. In the second Cl1- site, Cl1- is bonded in a 1-coordinate geometry to four K1+ and one Re+3.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Re3Se4O9 by Materials Project

Re3Se4O3(O2)3 crystallizes in the trigonal R-3m space group. The structure is zero-dimensional and consists of eighteen hydrogen peroxide molecules and three Re3Se4O3 clusters. In each Re3Se4O3 cluster, Re+6.67+ is bonded in a distorted single-bond geometry to four Se+0.50- and one O2- atom. There are a spread of Re–Se bond distances ranging from 2.52–2.54 Å. The Re–O bond length is 1.70 Å. There are two inequivalent Se+0.50- sites. In the first Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three equivalent Re+6.67+ atoms. In the second Se+0.50- site, Se+0.50- is bonded in a 3-coordinate geometry to three equivalent Re+6.67+ atoms. O2- is bonded in a single-bond geometry to one Re+6.67+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3(ReO5)2 by Materials Project

Pr3(ReO5)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.42–2.57 Å. In the second Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.39–2.73 Å. Re+5.50+ is bonded to six O2- atoms to form edge-sharing ReO6 octahedra. There are a spread of Re–O bond distances ranging from 1.89–2.05 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to three Pr3+ and one Re+5.50+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Pr3+ and two equivalent Re+5.50+ atoms. In the third O2- site, O2- is bonded in a trigonal non-coplanar geometry to two equivalent Pr3+ and one Re+5.50+ atom. In the fourth O2- site, O2- is bonded to three Pr3+ and one Re+5.50+ atom to form a mixture of edge and corner-sharing OPr3Re tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cs3Re2Cl10O by Materials Project

Cs3Re2OCl10 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded to twelve Cl1- atoms to form CsCl12 cuboctahedra that share corners with four equivalent CsCl12 cuboctahedra, faces with four equivalent CsCl12 cuboctahedra, and faces with four equivalent ReCl5O octahedra. There are eight shorter (3.68 Å) and four longer (3.81 Å) Cs–Cl bond lengths. In the second Cs1+ site, Cs1+ is bonded in a body-centered cubic geometry to eight equivalent Cl1- atoms. All Cs–Cl bond lengths are 3.59 Å. Re+4.50+ is bonded to one O2- and five Cl1- atoms to form ReCl5O octahedra that share a cornercorner with one ReCl5O octahedra and faces with four equivalent CsCl12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. The Re–O bond length is 1.83 Å. There are four shorter (2.38 Å) and one longer (2.39 Å) Re–Cl bond lengths. O2- is bonded in a linear geometry to two equivalent Re+4.50+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to four equivalent Cs1+ and one Re+4.50+ atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to three Cs1+ and one Re+4.50+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KRe3(SO)4 by Materials Project

KRe3(SO)4 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one KRe3(SO)4 ribbon oriented in the (0, 1, -1) direction. K1+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of K–O bond distances ranging from 2.55–3.00 Å. There are three inequivalent Re5+ sites. In the first Re5+ site, Re5+ is bonded in a distorted single-bond geometry to four S2- and one O2- atom. There are a spread of Re–S bond distances ranging from 2.38–2.41 Å. The Re–O bond length is 1.71 Å. In the second Re5+ site, Re5+ is bonded in a distorted single-bond geometry to four S2- and one O2- atom. There are one shorter (2.39 Å) and three longer (2.40 Å) Re–S bond lengths. The Re–O bond length is 1.70 Å. In the third Re5+ site, Re5+ is bonded in a distorted single-bond geometry to four S2- and one O2- atom. There are two shorter (2.39 Å) and two longer (2.40 Å) Re–S bond lengths. The Re–O bond length is 1.70 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to three Re5+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three Re5+ atoms. In the third S2- site, S2- is bonded in a 4-coordinate geometry to three Re5+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to three Re5+ atoms. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Re5+ atom. In the second O2- site, O2- is bonded in a water-like geometry to two equivalent K1+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one Re5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Re5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2022

A Moving Embedded Boundary Approach for the Compressible Navier-Stokes Equations in a Block-Structured Adaptive Refinement Framework

A computational technique has been developed to perform compressible flow simulations involving moving boundaries using an embedded boundary approach within the block-structured adaptive mesh refinement (SAMR) framework of AMReX [1], [91], [92]. We leverage the SAMR capability to obtain quantitatively accurate results whilst using robust, second-order finite volume schemes. A conservative, unsplit, cut-cell approach is utilized and a ghost-cell approach is developed for computing the flux on the moving, embedded boundary faces. A third-order least-squares formulation has been developed to compute the wall velocity gradients, and was found to significantly improve the performance of the solver in terms of the quantitative comparison of surface quantities such as the skin friction coefficient. Various test cases are performed to validate the method, and compared with analytical, experimental, and other numerical results in literature. Inviscid and viscous test cases are performed that span a wide regime of flow speeds - acoustic (harmonically pulsating sphere), smooth flows (expansion fan created by a receding piston) and flows with shocks (shock-cylinder interaction, shock-wedge interaction, pitching NACA 0012 airfoil and shock-cone interaction). A closed system with moving boundaries - an oscillating piston in a cylinder, showed that the percentage error in mass within the system decreases with refinement, demonstrating that the numerical scheme is conservative with grid refinement, but is not discretely conservative. Viscous test cases involve that of a horizontally moving cylinder at Re = 40, an inline oscillating cylinder at Re = 100, and a transversely oscillating cylinder at Re = 185. The judicious use of adaptive mesh refinement with appropriate refinement criteria to capture the regions of interest leads to well-resolved flow features, and good quantitative comparison is observed with the results available in literature.

adaptive refinement↗