cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.17188/1730825
title: Materials Data on Rb3Tm by Materials Project

description: Rb3Tm is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Rb is bonded to eight equivalent Rb and four equivalent Tm atoms to form distorted RbRb8Tm4 cuboctahedra that share corners with twelve equivalent RbRb8Tm4 cuboctahedra, edges with eight equivalent TmRb12 cuboctahedra, edges with sixteen equivalent RbRb8Tm4 cuboctahedra, faces with four equivalent TmRb12 cuboctahedra, and faces with fourteen equivalent RbRb8Tm4 cuboctahedra. All Rb–Rb bond lengths are 4.54 Å. All Rb–Tm bond lengths are 4.54 Å. Tm is bonded to twelve equivalent Rb atoms to form TmRb12 cuboctahedra that share corners with twelve equivalent TmRb12 cuboctahedra, edges with twenty-four equivalent RbRb8Tm4 cuboctahedra, faces with six equivalent TmRb12 cuboctahedra, and faces with twelve equivalent RbRb8Tm4 cuboctahedra.
DOI: 10.17188/1730826
title: Materials Data on Ho3Ge13Os4 by Materials Project

description: Ho3Os4Ge13 crystallizes in the cubic Pm-3n space group. The structure is three-dimensional. Ho is bonded in a 8-coordinate geometry to four equivalent Os and twelve equivalent Ge atoms. All Ho–Os bond lengths are 3.20 Å. There are eight shorter (3.18 Å) and four longer (3.24 Å) Ho–Ge bond lengths. Os is bonded in a 6-coordinate geometry to three equivalent Ho and six equivalent Ge atoms. All Os–Ge bond lengths are 2.50 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 2-coordinate geometry to three equivalent Ho, two equivalent Os, and one Ge atom. The Ge–Ge bond length is 3.03 Å. In the second Ge site, Ge is bonded in a cuboctahedral geometry to twelve equivalent Ge atoms.
DOI: 10.17188/1730827
title: Materials Data on Mg2Si3 by Materials Project

description: Mg2Si3 is Magnesium tetraboride-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to six Si+1.33- atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.20 Å. In the second Mg2+ site, Mg2+ is bonded in a 1-coordinate geometry to nine Si+1.33- atoms. There are a spread of Mg–Si bond distances ranging from 2.75–3.19 Å. In the third Mg2+ site, Mg2+ is bonded in a 7-coordinate geometry to seven Si+1.33- atoms. There are a spread of Mg–Si bond distances ranging from 2.74–3.09 Å. In the fourth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five Si+1.33- atoms. There are a spread of Mg–Si bond distances ranging from 2.71–3.00 Å. There are six inequivalent Si+1.33- sites. In the first Si+1.33- site, Si+1.33- is bonded in a 1-coordinate geometry to four Mg2+ and four Si+1.33- atoms. There are a spread of Si–Si bond distances ranging from 2.46–2.81 Å. In the second Si+1.33- site, Si+1.33- is bonded in a 9-coordinate geometry to four Mg2+ and five Si+1.33- atoms. There are a spread of Si–Si bond distances ranging from 2.43–2.51 Å. In the third Si+1.33- site, Si+1.33- is bonded in a 8-coordinate geometry to five Mg2+ and three Si+1.33- atoms. There are one shorter (2.43 Å) and one longer (2.50 Å) Si–Si bond lengths. In the fourth Si+1.33- site, Si+1.33- is bonded in a 8-coordinate geometry to seven Mg2+ and one Si+1.33- atom. In the fifth Si+1.33- site, Si+1.33- is bonded in a 2-coordinate geometry to five Mg2+ and four Si+1.33- atoms. In the sixth Si+1.33- site, Si+1.33- is bonded in a 6-coordinate geometry to two Mg2+ and four Si+1.33- atoms. The Si–Si bond length is 2.49 Å.
DOI: 10.17188/1730828
title: Materials Data on MgCd3 by Materials Project

description: MgCd3 is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Mg is bonded in a body-centered cubic geometry to fourteen Cd atoms. There are eight shorter (3.07 Å) and six longer (3.54 Å) Mg–Cd bond lengths. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded in a distorted body-centered cubic geometry to six equivalent Mg and eight equivalent Cd atoms. All Cd–Cd bond lengths are 3.07 Å. In the second Cd site, Cd is bonded in a distorted body-centered cubic geometry to four equivalent Mg and four equivalent Cd atoms.
DOI: 10.17188/1730829
title: Materials Data on Li4V2Si4O13 by Materials Project

description: 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
DOI: 10.17188/1730831
title: Materials Data on MgIn2 by Materials Project

description: MgIn2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Mg is bonded to two equivalent Mg and ten equivalent In atoms to form a mixture of distorted face and edge-sharing MgMg2In10 cuboctahedra. Both Mg–Mg bond lengths are 3.22 Å. There are a spread of Mg–In bond distances ranging from 3.14–3.47 Å. In is bonded in a 12-coordinate geometry to five equivalent Mg and seven equivalent In atoms. There are a spread of In–In bond distances ranging from 3.20–3.48 Å.
DOI: 10.17188/1730832
title: Materials Data on LiFeP2O7 by Materials Project

description: 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
DOI: 10.17188/1730833
title: Materials Data on Li8Fe9CoO20 by Materials Project

description: 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
DOI: 10.17188/1730834
title: Materials Data on K2PrCuI6 by Materials Project

description: 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
DOI: 10.17188/1730835
title: Materials Data on Rb5Bi4 by Materials Project

description: Bi4Rb5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are five inequivalent Rb sites. In the first Rb site, Rb is bonded in a 7-coordinate geometry to seven Bi atoms. There are a spread of Rb–Bi bond distances ranging from 3.92–4.02 Å. In the second Rb site, Rb is bonded in a 7-coordinate geometry to seven Bi atoms. There are a spread of Rb–Bi bond distances ranging from 3.91–4.01 Å. In the third Rb site, Rb is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Rb–Bi bond distances ranging from 3.96–4.02 Å. In the fourth Rb site, Rb is bonded in a 6-coordinate geometry to six Bi atoms. There are a spread of Rb–Bi bond distances ranging from 3.90–4.12 Å. In the fifth Rb site, Rb is bonded in a distorted square co-planar geometry to four Bi atoms. There are two shorter (3.81 Å) and two longer (3.84 Å) Rb–Bi bond lengths. There are four inequivalent Bi sites. In the first Bi site, Bi is bonded in a 9-coordinate geometry to eight Rb and one Bi atom. The Bi–Bi bond length is 3.01 Å. In the second Bi site, Bi is bonded in a 9-coordinate geometry to eight Rb and one Bi atom. The Bi–Bi bond length is 3.02 Å. In the third Bi site, Bi is bonded in a 9-coordinate geometry to seven Rb and two Bi atoms. The Bi–Bi bond length is 3.07 Å. In the fourth Bi site, Bi is bonded in a 9-coordinate geometry to seven Rb and two Bi atoms.
DOI: 10.17188/1730836
title: Materials Data on PaTaO3 by Materials Project

description: PaTaO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Pa3+ is bonded to twelve equivalent O2- atoms to form PaO12 cuboctahedra that share corners with twelve equivalent PaO12 cuboctahedra, faces with six equivalent PaO12 cuboctahedra, and faces with eight equivalent TaO6 octahedra. All Pa–O bond lengths are 2.86 Å. Ta3+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent TaO6 octahedra and faces with eight equivalent PaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–O bond lengths are 2.02 Å. O2- is bonded in a distorted linear geometry to four equivalent Pa3+ and two equivalent Ta3+ atoms.
DOI: 10.17188/1730837
title: Materials Data on C2N2O by Materials Project

description: C2NNO crystallizes in the hexagonal P6_3/m space group. The structure is zero-dimensional and consists of six amino(methylidyne)azanium molecules and six formaldehyde molecules.
DOI: 10.17188/1730838
title: Materials Data on MgZrN2 by Materials Project

description: 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
DOI: 10.17188/1730839
title: Materials Data on RbUCrNO9 by Materials Project

description: RbUCrNO9 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Rb1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Rb–O bond distances ranging from 2.96–3.56 Å. U6+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.81–2.58 Å. Cr6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Cr–O bond distances ranging from 1.61–1.69 Å. N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.23 Å) and two longer (1.29 Å) N–O bond length. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+, one U6+, and one Cr6+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one Cr6+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+ and one Cr6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Rb1+, one U6+, and one N5+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one U6+, and one Cr6+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Rb1+ and one U6+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+ and one U6+ atom. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one Rb1+, one U6+, and one N5+ atom.
DOI: 10.17188/1730840
title: Materials Data on LiMnVP2(HO5)2 by Materials Project

description: 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
DOI: 10.17188/1730841
title: Materials Data on Na2Mg(SO6)2 by Materials Project

description: Na2Mg(SO6)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Na is bonded to six O atoms to form NaO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four equivalent SO4 tetrahedra, and an edgeedge with one NaO6 octahedra. The corner-sharing octahedra tilt angles range from 39–46°. There are a spread of Na–O bond distances ranging from 2.38–2.49 Å. Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent NaO6 octahedra and corners with two equivalent SO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–46°. There are a spread of Mg–O bond distances ranging from 2.03–2.09 Å. S is bonded to four O atoms to form SO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with four equivalent NaO6 octahedra. The corner-sharing octahedra tilt angles range from 34–55°. There are a spread of S–O bond distances ranging from 1.47–1.51 Å. There are six inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to one Na and one S atom. In the second O site, O is bonded in a distorted trigonal planar geometry to two equivalent Na and one S atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Mg and one S atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Na and one S atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Na and one Mg atom. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to one Na and one Mg atom.
DOI: 10.17188/1730842
title: Materials Data on MoPO5 by Materials Project

description: 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
DOI: 10.17188/1730843
title: Materials Data on Li5Mn2CoO8 by Materials Project

description: Li5Mn2CoO8 is Caswellsilverite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with three equivalent MnO6 octahedra, corners with three equivalent CoO6 octahedra, an edgeedge with one CoO6 octahedra, edges with three equivalent MnO6 octahedra, and edges with eight LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–9°. There are a spread of Li–O bond distances ranging from 2.07–2.27 Å. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with three equivalent LiO6 octahedra, corners with three equivalent MnO6 octahedra, edges with two equivalent CoO6 octahedra, edges with three equivalent MnO6 octahedra, and edges with seven LiO6 octahedra. The corner-sharing octahedra tilt angles range from 6–12°. There are a spread of Li–O bond distances ranging from 1.96–2.28 Å. In the third Li1+ site, Li1+ is bonded to six O2- atoms to form LiO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with four equivalent CoO6 octahedra, and edges with eight LiO6 octahedra. The corner-sharing octahedra tilt angles range from 7–12°. There are a spread of Li–O bond distances ranging from 2.01–2.22 Å. Mn+4.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six LiO6 octahedra, edges with six LiO6 octahedra, and edges with six equivalent MnO6 octahedra. The corner-sharing octahedra tilt angles range from 6–9°. There are a spread of Mn–O bond distances ranging from 1.95–2.22 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent LiO6 octahedra, edges with two equivalent CoO6 octahedra, and edges with ten LiO6 octahedra. The corner-sharing octahedra tilt angles range from 3–7°. There are a spread of Co–O bond distances ranging from 1.79–2.02 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded to three Li1+ and three equivalent Mn+4.50+ atoms to form a mixture of corner and edge-sharing OLi3Mn3 octahedra. The corner-sharing octahedra tilt angles range from 1–8°. In the second O2- site, O2- is bonded to five Li1+ and one Co2+ atom to form OLi5Co octahedra that share corners with six OLi5Co octahedra and edges with twelve OLi3Mn3 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. In the third O2- site, O2- is bonded to three Li1+ and three equivalent Mn+4.50+ atoms to form a mixture of corner and edge-sharing OLi3Mn3 octahedra. The corner-sharing octahedra tilt angles range from 1–8°. In the fourth O2- site, O2- is bonded to four Li1+ and two equivalent Co2+ atoms to form a mixture of corner and edge-sharing OLi4Co2 octahedra. The corner-sharing octahedra tilt angles range from 0–8°.
DOI: 10.17188/1730844
title: Materials Data on Mg2MnV3S8 by Materials Project

description: 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
DOI: 10.17188/1730845
title: Materials Data on Li7Fe5OF15 by Materials Project

description: 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
DOI: 10.17188/1730846
title: Materials Data on K(Nb3Se4)2 by Materials Project

description: K(Nb3Se4)2 crystallizes in the trigonal P-3 space group. The structure is three-dimensional. K1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. All K–Se bond lengths are 3.34 Å. Nb+2.50+ is bonded to six Se2- atoms to form a mixture of distorted edge, corner, and face-sharing NbSe6 octahedra. The corner-sharing octahedra tilt angles range from 45–54°. There are a spread of Nb–Se bond distances ranging from 2.61–2.85 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded to six equivalent Nb+2.50+ atoms to form distorted face-sharing SeNb6 pentagonal pyramids. In the second Se2- site, Se2- is bonded in a 5-coordinate geometry to one K1+ and four equivalent Nb+2.50+ atoms.
DOI: 10.17188/1730847
title: Materials Data on HoU2S3O2 by Materials Project

description: U2HoS3O2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. U+3.50+ is bonded in a 4-coordinate geometry to four equivalent S2- and four equivalent O2- atoms. All U–S bond lengths are 2.95 Å. All U–O bond lengths are 2.33 Å. Ho3+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing HoS6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.69 Å) and two longer (2.72 Å) Ho–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 1-coordinate geometry to four equivalent U+3.50+ and one Ho3+ atom. In the second S2- site, S2- is bonded in a square co-planar geometry to four equivalent Ho3+ atoms. O2- is bonded to four equivalent U+3.50+ atoms to form a mixture of edge and corner-sharing OU4 tetrahedra.
DOI: 10.17188/1730848
title: Materials Data on TeO4 by Materials Project

description: TeO4 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one TeO4 sheet oriented in the (0, 0, 1) direction. Te is bonded to six O atoms to form corner-sharing TeO6 octahedra. The corner-sharing octahedral tilt angles are 46°. There is two shorter (1.95 Å) and four longer (1.96 Å) Te–O bond length. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Te atom. In the second O site, O is bonded in a distorted bent 120 degrees geometry to two equivalent Te atoms.
DOI: 10.17188/1730849
title: Materials Data on Mn3(CrN2)2 by Materials Project

description: 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
DOI: 10.17188/1730850
title: Materials Data on CaSO6 by Materials Project

description: CaSO6 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.96 Å. S is bonded in a distorted water-like geometry to four O atoms. There is two shorter (1.49 Å) and two longer (2.27 Å) S–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to two equivalent Ca, one S, and one O atom. The O–O bond length is 1.47 Å. In the second O site, O is bonded in a water-like geometry to one Ca and one S atom. In the third O site, O is bonded in a linear geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the fourth O site, O is bonded in a linear geometry to one Ca and one O atom. The O–O bond length is 1.23 Å.
DOI: 10.17188/1730851
title: Materials Data on Cs2TlRuF6 by Materials Project

description: 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
DOI: 10.17188/1730852
title: Materials Data on Na3GaN2 by Materials Project

description: 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
DOI: 10.17188/1730853
title: Materials Data on Pm2NiPt by Materials Project

description: Pm2PtNi is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Pm is bonded in a body-centered cubic geometry to four equivalent Pt and four equivalent Ni atoms. All Pm–Pt bond lengths are 3.07 Å. All Pm–Ni bond lengths are 3.07 Å. Pt is bonded in a body-centered cubic geometry to eight equivalent Pm atoms. Ni is bonded in a body-centered cubic geometry to eight equivalent Pm atoms.
DOI: 10.17188/1730855
title: Materials Data on LiTi3MnCr(PO4)6 by Materials Project

description: 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
DOI: 10.17188/1730856
title: Materials Data on Nd2Si3 by Materials Project

description: Nd2Si3 crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Nd2+ is bonded in a 9-coordinate geometry to nine Si+1.33- atoms. There are three shorter (3.10 Å) and six longer (3.14 Å) Nd–Si bond lengths. There are three inequivalent Si+1.33- sites. In the first Si+1.33- site, Si+1.33- is bonded in a 9-coordinate geometry to six equivalent Nd2+ and three equivalent Si+1.33- atoms. All Si–Si bond lengths are 2.34 Å. In the second Si+1.33- site, Si+1.33- is bonded to six equivalent Nd2+ atoms to form distorted edge-sharing SiNd6 pentagonal pyramids. In the third Si+1.33- site, Si+1.33- is bonded in a 9-coordinate geometry to six equivalent Nd2+ and three equivalent Si+1.33- atoms.
DOI: 10.17188/1730857
title: Materials Data on VOF3 by Materials Project

description: 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
DOI: 10.17188/1730858
title: Materials Data on SnCNCl3 by Materials Project

description: SnCl2CNCl crystallizes in the monoclinic Pc space group. The structure is two-dimensional and consists of two cyanogen chloride molecules and one SnCl2 sheet oriented in the (0, 1, 0) direction. In the SnCl2 sheet, Sn2+ is bonded to four Cl1- atoms to form distorted corner-sharing SnCl4 tetrahedra. There are a spread of Sn–Cl bond distances ranging from 2.59–2.98 Å. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a bent 150 degrees geometry to two equivalent Sn2+ atoms. In the second Cl1- site, Cl1- is bonded in a linear geometry to two equivalent Sn2+ atoms.