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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Se2O5 by Materials Project

Se2O5 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of two Se2O5 ribbons oriented in the (0, 1, 0) direction. there are two inequivalent Se5+ sites. In the first Se5+ site, Se5+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.62–1.94 Å. In the second Se5+ site, Se5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Se–O bond distances ranging from 1.63–1.76 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Se5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two Se5+ atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one Se5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two Se5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrFe2C10(Se2O5)2 by Materials Project

CrFe2C10(Se2O5)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four CrFe2C10(Se2O5)2 clusters. Cr6+ is bonded to four C+1.60+ and two Se2- atoms to form CrC4Se2 octahedra that share corners with two FeC3Se3 octahedra. The corner-sharing octahedra tilt angles range from 60–62°. There are a spread of Cr–C bond distances ranging from 1.86–1.93 Å. There are one shorter (2.46 Å) and one longer (2.47 Å) Cr–Se bond lengths. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to three C+1.60+ and three Se2- atoms to form distorted FeC3Se3 octahedra that share a cornercorner with one CrC4Se2 octahedra and an edgeedge with one FeC3Se3 octahedra. The corner-sharing octahedral tilt angles are 62°. There is one shorter (1.80 Å) and two longer (1.82 Å) Fe–C bond length. There are a spread of Fe–Se bond distances ranging from 2.44–2.49 Å. In the second Fe3+ site, Fe3+ is bonded to three C+1.60+ and three Se2- atoms to form distorted FeC3Se3 octahedra that share a cornercorner with one CrC4Se2 octahedra and an edgeedge with one FeC3Se3 octahedra. The corner-sharing octahedral tilt angles are 60°. There are a spread of Fe–C bond distances ranging from 1.80–1.84 Å. There are a spread of Fe–Se bond distances ranging from 2.44–2.48 Å. There are ten inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a distorted single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the second C+1.60+ site, C+1.60+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the third C+1.60+ site, C+1.60+ is bonded in a distorted single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the fourth C+1.60+ site, C+1.60+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the fifth C+1.60+ site, C+1.60+ is bonded in a single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the sixth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Cr6+ and one O2- atom. The C–O bond length is 1.17 Å. In the seventh C+1.60+ site, C+1.60+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.15 Å. In the eighth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Cr6+ and one O2- atom. The C–O bond length is 1.17 Å. In the ninth C+1.60+ site, C+1.60+ is bonded in a distorted linear geometry to one Cr6+ and one O2- atom. The C–O bond length is 1.16 Å. In the tenth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Cr6+ and one O2- atom. The C–O bond length is 1.17 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted L-shaped geometry to two Fe3+ atoms. In the second Se2- site, Se2- is bonded in a distorted bent 120 degrees geometry to one Cr6+ and one Fe3+ atom. In the third Se2- site, Se2- is bonded in a distorted bent 120 degrees geometry to one Cr6+ and one Fe3+ atom. In the fourth Se2- site, Se2- is bonded in a distorted L-shaped geometry to two Fe3+ atoms. There are ten 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. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Th(Se2O5)2 by Materials Project

Th(Se2O5)2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Th4+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Th–O bond distances ranging from 2.37–2.55 Å. There are four inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.69–1.86 Å. In the second Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.69–1.89 Å. In the third Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.70 Å) and one longer (1.86 Å) Se–O bond length. In the fourth Se4+ site, Se4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.69–1.83 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two Se4+ atoms. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Se4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Th4+ and one Se4+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Se4+ atoms. In the fifth O2- site, O2- is bonded in a linear geometry to one Th4+ and one Se4+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Th4+ and one Se4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Se4+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Se4+ atom. In the ninth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Th4+ and one Se4+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Th4+ and one Se4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr6Fe5Ag3(Se2O5)2 by Materials Project

Sr6Fe5Ag3(Se2O5)2 crystallizes in the orthorhombic C222 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight equivalent FeO5 square pyramids. There are a spread of Sr–O bond distances ranging from 2.84–3.03 Å. In the second Sr2+ site, Sr2+ is bonded in a 4-coordinate geometry to four equivalent Se2- and four O2- atoms. There are a spread of Sr–Se bond distances ranging from 3.28–3.40 Å. There are a spread of Sr–O bond distances ranging from 2.48–2.51 Å. There are two inequivalent Fe+2.60+ sites. In the first Fe+2.60+ site, Fe+2.60+ is bonded to five O2- atoms to form FeO5 square pyramids that share corners with five equivalent FeO5 square pyramids and faces with four equivalent SrO12 cuboctahedra. There are a spread of Fe–O bond distances ranging from 1.94–2.05 Å. In the second Fe+2.60+ site, Fe+2.60+ is bonded in a 4-coordinate geometry to four equivalent Se2- atoms. All Fe–Se bond lengths are 2.63 Å. There are three inequivalent Ag1+ sites. In the first Ag1+ site, Ag1+ is bonded in a distorted tetrahedral geometry to four equivalent Se2- atoms. All Ag–Se bond lengths are 2.79 Å. In the second Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four equivalent Se2- atoms. All Ag–Se bond lengths are 2.72 Å. In the third Ag1+ site, Ag1+ is bonded in a 4-coordinate geometry to four equivalent Se2- atoms. All Ag–Se bond lengths are 2.71 Å. Se2- is bonded in a 8-coordinate geometry to four equivalent Sr2+, one Fe+2.60+, and three Ag1+ atoms. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two equivalent Fe+2.60+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and two equivalent Fe+2.60+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and two equivalent Fe+2.60+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and two equivalent Fe+2.60+ atoms. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to four Sr2+ and two equivalent Fe+2.60+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiFe(Se2O5)2 by Materials Project

LiFe(Se2O5)2 crystallizes in the orthorhombic Pnc2 space group. The structure is three-dimensional. Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share edges with two equivalent FeO6 octahedra. There are a spread of Li–O bond distances ranging from 2.15–2.23 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share edges with two equivalent LiO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.02–2.07 Å. There are two inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.89 Å. In the second Se4+ site, Se4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.71–1.86 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Li1+ and one Se4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Fe3+, and one Se4+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Se4+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Fe3+ and one Se4+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Li1+, one Fe3+, and one Se4+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Se4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cr2(Se2O5)3 by Materials Project

Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SrRe3Se4O11 by Materials Project

(SrRe3(Se2O5)2)2O2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one hydrogen peroxide molecule and one SrRe3(Se2O5)2 sheet oriented in the (0, 1, 0) direction. In the SrRe3(Se2O5)2 sheet, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.41–2.78 Å. There are three inequivalent Re+6.67+ sites. In the first Re+6.67+ site, Re+6.67+ is bonded in a water-like geometry to two O2- atoms. There is one shorter (1.73 Å) and one longer (1.78 Å) Re–O bond length. In the second Re+6.67+ site, Re+6.67+ is bonded in a distorted single-bond geometry to four Se and one O2- atom. There are a spread of Re–Se bond distances ranging from 2.47–2.50 Å. The Re–O bond length is 1.71 Å. In the third Re+6.67+ site, Re+6.67+ is bonded in a distorted single-bond geometry to four Se and one O2- atom. There are a spread of Re–Se bond distances ranging from 2.49–2.54 Å. The Re–O bond length is 1.70 Å. There are four inequivalent Se sites. In the first Se site, Se is bonded in a 2-coordinate geometry to two Re+6.67+ atoms. In the second Se site, Se is bonded in a 3-coordinate geometry to two Re+6.67+ and one O2- atom. The Se–O bond length is 2.93 Å. In the third Se site, Se is bonded in a 2-coordinate geometry to two Re+6.67+ atoms. In the fourth Se site, Se is bonded in a 2-coordinate geometry to two Re+6.67+ and one O2- atom. The Se–O bond length is 3.02 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted L-shaped geometry to one Sr2+ and one O2- atom. The O–O bond length is 1.45 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one O2- atom. The O–O bond length is 1.24 Å. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one O2- atom. The O–O bond length is 1.31 Å. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Re+6.67+ and one Se atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one Re+6.67+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one Re+6.67+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Sr2+ and one O2- atom. The O–O bond length is 1.37 Å. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two O2- atoms. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to one Sr2+ and one O2- atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+, one Re+6.67+, and one Se atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H8Se2N2O5 by Materials Project

(NH4)2Se2O5 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of eight ammonium molecules and four Se2O5 clusters. In each Se2O5 cluster, there are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.87 Å. In the second Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.90 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Se2- atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Se2- atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H8Se2N2O5 by Materials Project

(NH4)2Se2O5 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of eight ammonium molecules and four Se2O5 clusters. In each Se2O5 cluster, there are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.69–1.87 Å. In the second Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.69 Å) and one longer (1.91 Å) Se–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Se2- atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two Se2- atoms. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CrHSe3O8 by Materials Project

Cr(SeO2OH)(Se2O5) crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Cr(SeO2OH)(Se2O5) sheet oriented in the (-1, 0, 2) direction. Cr5+ is bonded in a distorted octahedral geometry to six O2- atoms. There are a spread of Cr–O bond distances ranging from 1.68–2.21 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are three inequivalent Se+3.33+ sites. In the first Se+3.33+ site, Se+3.33+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.68–1.88 Å. In the second Se+3.33+ site, Se+3.33+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.66–2.05 Å. In the third Se+3.33+ site, Se+3.33+ is bonded in an L-shaped geometry to two O2- atoms. Both Se–O bond lengths are 1.72 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Cr5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr5+ and one Se+3.33+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Cr5+ and one Se+3.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one Se+3.33+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two Se+3.33+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Cr5+, one H1+, and one Se+3.33+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr5+ and one Se+3.33+ atom. In the eighth O2- site, O2- is bonded in a bent 150 degrees geometry to one Cr5+ and one Se+3.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3Se3(ClO4)2 by Materials Project

Sr3(SeO3)(Se2O5)Cl2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to eight O2- and two equivalent Cl1- atoms. There are a spread of Sr–O bond distances ranging from 2.62–2.95 Å. There are one shorter (3.15 Å) and one longer (3.33 Å) Sr–Cl bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to five O2- and three equivalent Cl1- atoms. There are a spread of Sr–O bond distances ranging from 2.56–2.60 Å. There are one shorter (3.04 Å) and two longer (3.12 Å) Sr–Cl bond lengths. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to eight O2- and one Cl1- atom. There are a spread of Sr–O bond distances ranging from 2.59–2.98 Å. The Sr–Cl bond length is 3.12 Å. There are three inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.72 Å) and two longer (1.74 Å) Se–O bond length. In the second Se4+ site, Se4+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is two shorter (1.70 Å) and one longer (1.88 Å) Se–O bond length. In the third Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.69 Å) and one longer (1.87 Å) Se–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Se4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Se4+ atom. In the third O2- site, O2- is bonded to three Sr2+ and one Se4+ atom to form a mixture of distorted edge and corner-sharing OSr3Se tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Se4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Sr2+ and two Se4+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted see-saw-like geometry to four Sr2+ atoms. In the second Cl1- site, Cl1- is bonded in a distorted bent 150 degrees geometry to two equivalent Sr2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg3Se4O5 by Materials Project

(Hg3Se2)(Se2O5) crystallizes in the triclinic P-1 space group. The structure is three-dimensional and consists of four selenium molecules and one Hg3Se2O5 framework. In the Hg3Se2O5 framework, there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Hg–O bond distances ranging from 2.56–2.86 Å. In the second Hg2+ site, Hg2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Hg–O bond distances ranging from 2.55–2.91 Å. In the third Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to three O2- atoms. There are a spread of Hg–O bond distances ranging from 2.71–3.00 Å. There are two inequivalent Se1+ sites. In the first Se1+ site, Se1+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.70 Å) and one longer (1.88 Å) Se–O bond length. In the second Se1+ site, Se1+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Se–O bond distances ranging from 1.69–1.89 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two Se1+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Hg2+ and one Se1+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Hg2+ and one Se1+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Hg2+ and one Se1+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one Se1+ atom.

36 MATERIALS SCIENCE↗