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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on U2B6W by Materials Project

U2WB6 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent U3+ sites. In the first U3+ site, U3+ is bonded in a 2-coordinate geometry to fourteen B2- atoms. There are a spread of U–B bond distances ranging from 2.64–2.80 Å. In the second U3+ site, U3+ is bonded in a 12-coordinate geometry to one U3+ and twelve B2- atoms. The U–U bond length is 2.53 Å. There are a spread of U–B bond distances ranging from 2.63–2.74 Å. W6+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of W–B bond distances ranging from 2.37–2.42 Å. There are six inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent U3+, two equivalent W6+, and three B2- atoms. There are a spread of B–B bond distances ranging from 1.78–1.83 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four U3+, two equivalent W6+, and three B2- atoms. There is one shorter (1.69 Å) and one longer (1.81 Å) B–B bond length. In the third B2- site, B2- is bonded in a 9-coordinate geometry to four U3+, two equivalent W6+, and three B2- atoms. There is one shorter (1.77 Å) and one longer (1.79 Å) B–B bond length. In the fourth B2- site, B2- is bonded in a 9-coordinate geometry to four U3+, two equivalent W6+, and three B2- atoms. There is one shorter (1.68 Å) and one longer (1.83 Å) B–B bond length. In the fifth B2- site, B2- is bonded in a 9-coordinate geometry to four U3+, two equivalent W6+, and three B2- atoms. In the sixth B2- site, B2- is bonded in a 8-coordinate geometry to six U3+ and two B2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Tm2B6Os by Materials Project

Tm2OsB6 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Tm3+ sites. In the first Tm3+ site, Tm3+ is bonded in a 12-coordinate geometry to fourteen B2- atoms. There are a spread of Tm–B bond distances ranging from 2.70–2.79 Å. In the second Tm3+ site, Tm3+ is bonded to twelve B2- atoms to form a mixture of face and edge-sharing TmB12 cuboctahedra. There are a spread of Tm–B bond distances ranging from 2.57–2.60 Å. Os6+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of Os–B bond distances ranging from 2.33–2.39 Å. There are six inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Tm3+, two equivalent Os6+, and three B2- atoms. There are a spread of B–B bond distances ranging from 1.78–1.81 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four Tm3+, two equivalent Os6+, and three B2- atoms. There is one shorter (1.80 Å) and one longer (1.81 Å) B–B bond length. In the third B2- site, B2- is bonded in a 9-coordinate geometry to four Tm3+, two equivalent Os6+, and three B2- atoms. There is one shorter (1.73 Å) and one longer (1.84 Å) B–B bond length. In the fourth B2- site, B2- is bonded in a 9-coordinate geometry to four Tm3+, two equivalent Os6+, and three B2- atoms. Both B–B bond lengths are 1.79 Å. In the fifth B2- site, B2- is bonded in a 9-coordinate geometry to four Tm3+, two equivalent Os6+, and three B2- atoms. In the sixth B2- site, B2- is bonded in a 9-coordinate geometry to six Tm3+ and three B2- atoms. The B–B bond length is 2.10 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2B6Os by Materials Project

Y2OsB6 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 6-coordinate geometry to fourteen B2- atoms. There are a spread of Y–B bond distances ranging from 2.73–2.82 Å. In the second Y3+ site, Y3+ is bonded to twelve B2- atoms to form a mixture of edge and face-sharing YB12 cuboctahedra. There are a spread of Y–B bond distances ranging from 2.61–2.63 Å. Os6+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of Os–B bond distances ranging from 2.35–2.41 Å. There are six inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Y3+, two equivalent Os6+, and three B2- atoms. There are a spread of B–B bond distances ranging from 1.78–1.84 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Os6+, and three B2- atoms. Both B–B bond lengths are 1.81 Å. In the third B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Os6+, and three B2- atoms. There is one shorter (1.73 Å) and one longer (1.88 Å) B–B bond length. In the fourth B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Os6+, and three B2- atoms. There is one shorter (1.79 Å) and one longer (1.80 Å) B–B bond length. In the fifth B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Os6+, and three B2- atoms. In the sixth B2- site, B2- is bonded in a 9-coordinate geometry to six Y3+ and three B2- atoms. The B–B bond length is 2.17 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Y2B6Ru by Materials Project

Y2RuB6 crystallizes in the orthorhombic Pbam space group. The structure is three-dimensional. there are two inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded in a 6-coordinate geometry to fourteen B2- atoms. There are a spread of Y–B bond distances ranging from 2.73–2.81 Å. In the second Y3+ site, Y3+ is bonded to twelve B2- atoms to form a mixture of face and edge-sharing YB12 cuboctahedra. There are a spread of Y–B bond distances ranging from 2.61–2.64 Å. Ru6+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of Ru–B bond distances ranging from 2.35–2.41 Å. There are six inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Y3+, two equivalent Ru6+, and three B2- atoms. There are a spread of B–B bond distances ranging from 1.78–1.84 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Ru6+, and three B2- atoms. There is one shorter (1.81 Å) and one longer (1.82 Å) B–B bond length. In the third B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Ru6+, and three B2- atoms. There is one shorter (1.73 Å) and one longer (1.88 Å) B–B bond length. In the fourth B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Ru6+, and three B2- atoms. Both B–B bond lengths are 1.79 Å. In the fifth B2- site, B2- is bonded in a 9-coordinate geometry to four Y3+, two equivalent Ru6+, and three B2- atoms. In the sixth B2- site, B2- is bonded in a 9-coordinate geometry to six Y3+ and three B2- atoms. The B–B bond length is 2.16 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V5B6 by Materials Project

V5B6 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are three inequivalent V+2.40+ sites. In the first V+2.40+ site, V+2.40+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of V–B bond distances ranging from 2.24–2.33 Å. In the second V+2.40+ site, V+2.40+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of V–B bond distances ranging from 2.22–2.33 Å. In the third V+2.40+ site, V+2.40+ is bonded to twelve B2- atoms to form a mixture of edge and face-sharing VB12 cuboctahedra. There are eight shorter (2.30 Å) and four longer (2.36 Å) V–B bond lengths. There are three inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to seven V+2.40+ and two equivalent B2- atoms. Both B–B bond lengths are 1.76 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to six V+2.40+ and three B2- atoms. The B–B bond length is 1.73 Å. In the third B2- site, B2- is bonded in a 9-coordinate geometry to seven V+2.40+ and two equivalent B2- atoms. Both B–B bond lengths are 1.80 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb5B6 by Materials Project

Nb5B6 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. there are three inequivalent Nb+2.40+ sites. In the first Nb+2.40+ site, Nb+2.40+ is bonded to twelve B2- atoms to form a mixture of edge and face-sharing NbB12 cuboctahedra. There are eight shorter (2.47 Å) and four longer (2.50 Å) Nb–B bond lengths. In the second Nb+2.40+ site, Nb+2.40+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of Nb–B bond distances ranging from 2.38–2.60 Å. In the third Nb+2.40+ site, Nb+2.40+ is bonded in a 7-coordinate geometry to seven B2- atoms. There are a spread of Nb–B bond distances ranging from 2.42–2.59 Å. There are three inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to seven Nb+2.40+ and two equivalent B2- atoms. Both B–B bond lengths are 1.85 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to seven Nb+2.40+ and two equivalent B2- atoms. Both B–B bond lengths are 1.88 Å. In the third B2- site, B2- is bonded in a 9-coordinate geometry to six Nb+2.40+ and three B2- atoms. The B–B bond length is 1.82 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb2(NiB2)3 by Materials Project

Yb2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Yb3+ is bonded in a distorted q4 geometry to twelve B2- atoms. There are a spread of Yb–B bond distances ranging from 2.73–2.75 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.13 Å) and four longer (2.16 Å) Ni–B bond lengths. In the second Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.25 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Yb3+, two equivalent Ni2+, and three B2- atoms. There is two shorter (1.71 Å) and one longer (1.74 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Yb3+, three Ni2+, and two B2- atoms. The B–B bond length is 1.72 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Er2(NiB2)3 by Materials Project

Er2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Er3+ is bonded in a 12-coordinate geometry to twelve B2- atoms. There are a spread of Er–B bond distances ranging from 2.72–2.75 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.12 Å) and four longer (2.16 Å) Ni–B bond lengths. In the second Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.22 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Er3+, two equivalent Ni2+, and three B2- atoms. There is one shorter (1.73 Å) and two longer (1.75 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Er3+, three Ni2+, and two B2- atoms. The B–B bond length is 1.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Lu2(NiB2)3 by Materials Project

Lu2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Lu3+ is bonded in a 12-coordinate geometry to twelve B2- atoms. There are a spread of Lu–B bond distances ranging from 2.70–2.73 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.10 Å) and four longer (2.15 Å) Ni–B bond lengths. In the second Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.20 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Lu3+, two equivalent Ni2+, and three B2- atoms. There is one shorter (1.71 Å) and two longer (1.75 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Lu3+, three Ni2+, and two B2- atoms. The B–B bond length is 1.72 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Materials Data on B6H6NO6 by Materials Project

(HBO1)3B3NH3O3 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of twelve borinic acid molecules and two B3NH3O3 clusters. In each B3NH3O3 cluster, there are three inequivalent B2+ sites. In the first B2+ site, B2+ is bonded in a single-bond geometry to one O2- atom. The B–O bond length is 1.41 Å. In the second B2+ site, B2+ is bonded in a single-bond geometry to one O2- atom. The B–O bond length is 1.38 Å. In the third B2+ site, B2+ is bonded in a single-bond geometry to one O2- atom. The B–O bond length is 1.38 Å. N2- is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of N–O bond distances ranging from 2.68–3.07 Å. There are three inequivalent H+0.33+ sites. In the first H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H+0.33+ site, H+0.33+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one B2+, one N2-, and one H+0.33+ atom. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one B2+, one N2-, and one H+0.33+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one B2+, two equivalent N2-, and one H+0.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Materials Data on Tm2(NiB2)3 by Materials Project

Tm2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Tm3+ is bonded in a 12-coordinate geometry to twelve B2- atoms. There are a spread of Tm–B bond distances ranging from 2.72–2.75 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.22 Å. In the second Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.12 Å) and four longer (2.16 Å) Ni–B bond lengths. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Tm3+, three Ni2+, and two B2- atoms. There is one shorter (1.73 Å) and one longer (1.75 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Tm3+, two equivalent Ni2+, and three B2- atoms. The B–B bond length is 1.73 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ho2(NiB2)3 by Materials Project

Ho2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ho3+ is bonded in a 12-coordinate geometry to twelve B2- atoms. There are a spread of Ho–B bond distances ranging from 2.73–2.75 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.23 Å. In the second Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.13 Å) and four longer (2.17 Å) Ni–B bond lengths. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Ho3+, three Ni2+, and two B2- atoms. There is one shorter (1.74 Å) and one longer (1.75 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Ho3+, two equivalent Ni2+, and three B2- atoms. The B–B bond length is 1.74 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Materials Data on Ce(CrB3)2 by Materials Project

CeCr2B6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Ce3+ is bonded in a 12-coordinate geometry to sixteen B2- atoms. There are a spread of Ce–B bond distances ranging from 2.80–2.97 Å. Cr+4.50+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are two shorter (2.12 Å) and eight longer (2.21 Å) Cr–B bond lengths. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to two equivalent Ce3+, four equivalent Cr+4.50+, and three B2- atoms. There is two shorter (1.75 Å) and one longer (1.86 Å) B–B bond length. In the second B2- site, B2- is bonded in a 6-coordinate geometry to three equivalent Ce3+, three equivalent Cr+4.50+, and three B2- atoms. Both B–B bond lengths are 1.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(CrB3)2 by Materials Project

ThCr2B6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Th4+ is bonded in a 12-coordinate geometry to sixteen B2- atoms. There are a spread of Th–B bond distances ranging from 2.83–2.98 Å. Cr4+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are two shorter (2.13 Å) and eight longer (2.23 Å) Cr–B bond lengths. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to two equivalent Th4+, four equivalent Cr4+, and three B2- atoms. There is two shorter (1.76 Å) and one longer (1.85 Å) B–B bond length. In the second B2- site, B2- is bonded in a 6-coordinate geometry to three equivalent Th4+, three equivalent Cr4+, and three B2- atoms. Both B–B bond lengths are 1.81 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U(FeB3)2 by Materials Project

UFe2B6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. U6+ is bonded in a 12-coordinate geometry to sixteen B2- atoms. There are a spread of U–B bond distances ranging from 2.66–2.89 Å. Fe3+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of Fe–B bond distances ranging from 2.02–2.18 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 6-coordinate geometry to three equivalent U6+, three equivalent Fe3+, and three B2- atoms. There is one shorter (1.70 Å) and two longer (1.79 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to two equivalent U6+, four equivalent Fe3+, and three B2- atoms. The B–B bond length is 1.78 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr(CrB3)2 by Materials Project

Pr(CrB3)2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Pr3+ is bonded in a 12-coordinate geometry to sixteen B2- atoms. There are a spread of Pr–B bond distances ranging from 2.85–2.96 Å. Cr+4.50+ is bonded in a 10-coordinate geometry to ten B2- atoms. There are a spread of Cr–B bond distances ranging from 2.14–2.23 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 6-coordinate geometry to three equivalent Pr3+, three equivalent Cr+4.50+, and three B2- atoms. There is one shorter (1.77 Å) and two longer (1.80 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to two equivalent Pr3+, four equivalent Cr+4.50+, and three B2- atoms. The B–B bond length is 1.82 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Nb2AlB6 by Materials Project

Nb2AlB6 is hexagonal omega structure-derived structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Nb+4.50+ is bonded to twelve B2- atoms to form NbB12 cuboctahedra that share edges with six equivalent NbB12 cuboctahedra, edges with six equivalent AlB12 cuboctahedra, a faceface with one AlB12 cuboctahedra, and faces with seven equivalent NbB12 cuboctahedra. There are six shorter (2.44 Å) and six longer (2.53 Å) Nb–B bond lengths. Al3+ is bonded to twelve equivalent B2- atoms to form AlB12 cuboctahedra that share edges with twelve equivalent NbB12 cuboctahedra, faces with two equivalent NbB12 cuboctahedra, and faces with six equivalent AlB12 cuboctahedra. All Al–B bond lengths are 2.41 Å. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to three equivalent Nb+4.50+, three equivalent Al3+, and three equivalent B2- atoms. All B–B bond lengths are 1.76 Å. In the second B2- site, B2- is bonded in a 9-coordinate geometry to six equivalent Nb+4.50+ and three equivalent B2- atoms. All B–B bond lengths are 1.76 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Phase relations in the Fe-FeSi system at high pressures and temperatures

The Earth's core is comprised mostly of iron and nickel, but it also contains several weight percent of one or more unknown light elements, which may include silicon. Therefore it is important to understand the high pressure, high temperature properties and behavior of alloys in the Fe–FeSi system, such as their phase diagrams. We determined melting temperatures and subsolidus phase relations of Fe–9 wt% Si and stoichiometric FeSi using synchrotron X-ray diffraction at high pressures and temperatures, up to ~200 GPa and ~145 GPa, respectively. Combining this data with that of previous studies, we generated phase diagrams in pressure–temperature, temperature–composition, and pressure–composition space. We find the B2 crystal structure in Fe–9Si where previous studies reported the less ordered bcc structure, and a shallower slope for the hcp+B2 to fcc+B2 boundary than previously reported. In stoichiometric FeSi, we report a wide B2+B20 two-phase field, with complete conversion to the B2 structure at ~42 GPa. The minimum temperature of an Fe–Si outer core is 4380 K, based on the eutectic melting point of Fe–9Si, and silicon is shown to be less efficient at depressing the melting point of iron at core conditions than oxygen or sulfur. At the highest pressures reached, only the hcp and B2 structures are seen in the Fe–FeSi system. We predict that alloys containing more than ~4–8 wt% silicon will convert to an hcp+B2 mixture and later to the hcp structure with increasing pressure, and that an iron–silicon alloy in the Earth's inner core would most likely be a mixture of hcp and B2 phases.

Fischer, Rebecca A.↗