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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
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
Co2(SO4)3N2 crystallizes in the cubic P2_13 space group. The structure is three-dimensional and consists of eight ammonia molecules and one Co2(SO4)3 framework. In the Co2(SO4)3 framework, there are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent SO4 tetrahedra. There are three shorter (2.01 Å) and three longer (2.03 Å) Co–O bond lengths. In the second Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Co–O bond lengths are 2.04 Å. S+3.33+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CoO6 octahedra. The corner-sharing octahedra tilt angles range from 13–47°. There is one shorter (1.46 Å) and three longer (1.49 Å) S–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Co2+ and one S+3.33+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Co2+ and one S+3.33+ atom. In the third O2- site, O2- is bonded in a linear geometry to one Co2+ and one S+3.33+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one S+3.33+ atom.
Co3C10O9Co5C14(SO4)3 is alpha La structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four Co3C10O9 clusters and four Co5C14(SO4)3 clusters. In each Co3C10O9 cluster, there are three inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded in a 4-coordinate geometry to four C+1.33+ atoms. There are a spread of Co–C bond distances ranging from 1.77–1.92 Å. In the second Co2+ site, Co2+ is bonded in a 4-coordinate geometry to four C+1.33+ atoms. There are a spread of Co–C bond distances ranging from 1.76–1.93 Å. In the third Co2+ site, Co2+ is bonded in a 4-coordinate geometry to four C+1.33+ atoms. There are a spread of Co–C bond distances ranging from 1.76–1.92 Å. There are ten inequivalent C+1.33+ sites. In the first C+1.33+ site, C+1.33+ is bonded in a 3-coordinate geometry to three Co2+ atoms. In the second C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.15 Å. In the fifth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the seventh C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the ninth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the tenth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.15 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In each Co5C14(SO4)3 cluster, there are five inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded in a 2-coordinate geometry to three C+1.33+ and two S2- atoms. There are a spread of Co–C bond distances ranging from 1.75–1.95 Å. There are one shorter (2.18 Å) and one longer (2.29 Å) Co–S bond lengths. In the second Co2+ site, Co2+ is bonded in a 4-coordinate geometry to four C+1.33+ atoms. There are a spread of Co–C bond distances ranging from 1.78–1.93 Å. In the third Co2+ site, Co2+ is bonded in a 2-coordinate geometry to three C+1.33+ and two S2- atoms. There are a spread of Co–C bond distances ranging from 1.75–1.95 Å. There are one shorter (2.18 Å) and one longer (2.29 Å) Co–S bond lengths. In the fourth Co2+ site, Co2+ is bonded in a 4-coordinate geometry to three C+1.33+ and one S2- atom. There are a spread of Co–C bond distances ranging from 1.76–1.88 Å. The Co–S bond length is 2.34 Å. In the fifth Co2+ site, Co2+ is bonded in a 4-coordinate geometry to three C+1.33+ and one S2- atom. There are a spread of Co–C bond distances ranging from 1.76–1.89 Å. The Co–S bond length is 2.34 Å. There are fourteen inequivalent C+1.33+ sites. In the first C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+1.33+ site, C+1.33+ is bonded in a distorted trigonal planar geometry to one Co2+ and two S2- atoms. Both C–S bond lengths are 1.74 Å. In the fifth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C+1.33+ site, C+1.33+ is bonded in a distorted single-bond geometry to two Co2+ and one O2- atom. The C–O bond length is 1.19 Å. In the seventh C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.15 Å. In the ninth C+1.33+ site, C+1.33+ is bonded in a 1-coordinate geometry to two Co2+ and one S2- atom. The C–S bond length is 1.75 Å. In the tenth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the eleventh C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the twelfth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the thirteenth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourteenth C+1.33+ site, C+1.33+ is bonded in a linear geometry to one Co2+ and one O2- atom. The C–O bond length is 1.16 Å. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two Co2+ and one C+1.33+ atom. In the second S2- site, S2- is bonded in a 3-coordinate geometry to two Co2+ and one C+1.33+ atom. In the third S2- site, S2- is bonded in a 3-coordinate geometry to two Co2+ and one C+1.33+ atom. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom. In the twelfth O2- site, O2- is bonded in a single-bond geometry to one C+1.33+ atom.
Rb2Co2(SO4)3 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Rb–O bond distances ranging from 2.91–3.22 Å. In the second Rb1+ site, Rb1+ is bonded in a 12-coordinate geometry to fifteen O2- atoms. There are a spread of Rb–O bond distances ranging from 2.95–3.49 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent SO4 tetrahedra. There are three shorter (2.10 Å) and three longer (2.13 Å) Co–O bond lengths. In the second Co2+ site, Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six equivalent SO4 tetrahedra. There are three shorter (2.11 Å) and three longer (2.15 Å) Co–O bond lengths. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CoO6 octahedra. The corner-sharing octahedra tilt angles range from 14–49°. There is two shorter (1.48 Å) and two longer (1.49 Å) S–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Co2+, and one S6+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to three Rb1+, one Co2+, and one S6+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Rb1+, one Co2+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two Rb1+, one Co2+, and one S6+ atom.
Li2Co2(SO4)3 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Li1+ is bonded to four O2- atoms to form distorted LiO4 trigonal pyramids that share corners with four SO4 tetrahedra and edges with two equivalent CoO6 octahedra. There is one shorter (1.93 Å) and three longer (1.95 Å) Li–O bond length. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six SO4 tetrahedra and edges with two equivalent LiO4 trigonal pyramids. There are a spread of Co–O bond distances ranging from 2.02–2.21 Å. There are two inequivalent S6+ sites. In the first S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four equivalent CoO6 octahedra and corners with two equivalent LiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 24–40°. There is two shorter (1.47 Å) and two longer (1.50 Å) S–O bond length. In the second S6+ site, S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four equivalent CoO6 octahedra and corners with three equivalent LiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 18–47°. There are a spread of S–O bond distances ranging from 1.46–1.50 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Co2+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Co2+ and one S6+ atom.
Spectra of Jupiter's icy satellites reveal surfaces dominated by water-ice, minor amounts of SO2 and CO2, and (for Europa) H2O2 along with hydrated materials. Jovian magnetospheric ions (protons, sulfur, and oxygen) and electrons significantly modify the chemical composition of these moons' surfaces in times ranging from a few years for Europa to thousands of years for Callisto at micrometer depths. Appropriate laboratory studies examining relevant volatile and non-volatile materials under low-temperature radiation conditions can provide information on likely radiation chemical mechanisms, on the stability and evolution of species, and on new species awaiting detection. Although the molecules detected on the icy moons are relatively simple, predicting their responses to radiation in space remains difficult. One problem is that there is a dearth of fundamental data examining solid-phase reactions. Our laboratory experiments have focused on infrared studies (2.5 to 25 microns) of a few simple irradiated ices. We have measured the spectra of proton-irradiated H2O ice containing SO2, H2S, and/or CO2. Ices with H2O/SO2 or H2O/H2S ratios of 3 and 30 have been irradiated at 86 K, 110 K, and 132 K. In irradiated H2O + SO2 ices new ions have been identified: SO4(-2), HSO4(-) and H3O(+). After warming to 260 K the residual spectrum is similar to that of H2SO4. Ices with H2O + H2S form SO2. After warming to 175 K, the residual sample matches the spectrum of hydrated H2SO4. H2O + CO2 ice forms carbonic acid, H2CO3 which is stable to temperatures near 230 K. In addition, OCS has been detected in irradiated ices containing H2O + SO2 + CO2. The radiation half-life of SO2 and H2S in H2O has been calculated. Our results give compelling evidence for the presence of new species awaiting detection. Future experiments will examine the signatures of these ices and hydrated materials in the 1 to 5 micron region, where possible weaker overtone bands may occur. In addition, absolute strengths for both the fundamental and overtone bands will be determined. Finally, good arguments can be made, based on current information, for remote sensing observations that have spectral coverage to at least 5 microns on the long wavelength end. This range would include some of the characteristic bands of H2O, H2O2, CO2, SO2, H2CO3, H2S, and OCS.
Sm2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Sm3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Sm–O bond distances ranging from 2.35–2.60 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are a spread of Co–O bond distances ranging from 2.06–2.14 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of S–O bond distances ranging from 1.47–1.52 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Sm3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sm3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Sm3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Sm3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Sm3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Sm3+, one Co2+, and one Te4+ atom.
Ho2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.26–2.57 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are a spread of Co–O bond distances ranging from 2.05–2.13 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of S–O bond distances ranging from 1.48–1.51 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Ho3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ho3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ho3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ho3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ho3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Ho3+, one Co2+, and one Te4+ atom.
Dy2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Dy3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Dy–O bond distances ranging from 2.27–2.57 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are a spread of Co–O bond distances ranging from 2.05–2.14 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.91 Å) and one longer (1.92 Å) Te–O bond length. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of S–O bond distances ranging from 1.48–1.51 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Dy3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Dy3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Dy3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Dy3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Dy3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Dy3+, one Co2+, and one Te4+ atom.
Eu2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Eu3+ is bonded to eight O2- atoms to form distorted EuO8 hexagonal bipyramids that share corners with two equivalent SO4 tetrahedra, edges with two equivalent EuO8 hexagonal bipyramids, an edgeedge with one CoO6 octahedra, and an edgeedge with one SO4 tetrahedra. There are a spread of Eu–O bond distances ranging from 2.42–2.70 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra and edges with two equivalent EuO8 hexagonal bipyramids. There are a spread of Co–O bond distances ranging from 1.94–2.14 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–1.95 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with two equivalent EuO8 hexagonal bipyramids, a cornercorner with one CoO6 octahedra, and an edgeedge with one EuO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 43°. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Eu3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Eu3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Eu3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Eu3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Eu3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Eu3+, one Co2+, and one Te4+ atom.
Gd2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Gd3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Gd–O bond distances ranging from 2.31–2.59 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are two shorter (2.05 Å) and four longer (2.13 Å) Co–O bond lengths. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 44°. There is three shorter (1.48 Å) and one longer (1.51 Å) S–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Gd3+ and one S6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Gd3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Gd3+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Gd3+ and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Gd3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Gd3+, one Co2+, and one Te4+ atom.
Y2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.28–2.57 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are two shorter (2.06 Å) and four longer (2.14 Å) Co–O bond lengths. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–1.92 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are a spread of S–O bond distances ranging from 1.48–1.51 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Y3+ and one Te4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Y3+, one Co2+, and one Te4+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Y3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Y3+, one Co2+, and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Y3+ and one S6+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Y3+ and one S6+ atom.
Yb2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Yb3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Yb–O bond distances ranging from 2.30–2.73 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.86–2.03 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.85–1.99 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of S–O bond distances ranging from 1.47–1.53 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Yb3+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Yb3+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Yb3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Co2+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Yb3+, one Co2+, and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Yb3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Yb3+ and one Te4+ atom.
Lu2CoTe2(SO7)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with three equivalent SO4 tetrahedra, an edgeedge with one CoO6 octahedra, and an edgeedge with one LuO7 pentagonal bipyramid. There are a spread of Lu–O bond distances ranging from 2.19–2.52 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with two equivalent SO4 tetrahedra and edges with two equivalent LuO7 pentagonal bipyramids. There are a spread of Co–O bond distances ranging from 2.05–2.14 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.90 Å) and one longer (1.92 Å) Te–O bond length. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share a cornercorner with one CoO6 octahedra and corners with three equivalent LuO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 50°. There is one shorter (1.48 Å) and three longer (1.49 Å) S–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Lu3+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Lu3+ and one S6+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Lu3+ and one S6+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Co2+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Lu3+, one Co2+, and one Te4+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Lu3+, one Co2+, and one Te4+ atom. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Lu3+ and one Te4+ atom.
LiCoSO4F crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a 5-coordinate geometry to four O2- and one F1- atom. There are a spread of Li–O bond distances ranging from 2.04–2.38 Å. The Li–F bond length is 1.87 Å. There are two inequivalent Co2+ sites. In the first Co2+ site, Co2+ is bonded to four O2- and two equivalent F1- atoms to form CoO4F2 octahedra that share corners with two equivalent CoO4F2 octahedra and corners with four equivalent SO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are two shorter (2.11 Å) and two longer (2.16 Å) Co–O bond lengths. Both Co–F bond lengths are 1.99 Å. In the second Co2+ site, Co2+ is bonded to four O2- and two equivalent F1- atoms to form CoO4F2 octahedra that share corners with two equivalent CoO4F2 octahedra and corners with four equivalent SO4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. There are two shorter (2.10 Å) and two longer (2.15 Å) Co–O bond lengths. Both Co–F bond lengths are 2.01 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four CoO4F2 octahedra. The corner-sharing octahedra tilt angles range from 35–53°. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co2+, and one S6+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+, one Co2+, and one S6+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Co2+, and one S6+ atom. F1- is bonded in a distorted trigonal planar geometry to one Li1+ and two Co2+ atoms.
Recent airborne thermal infrared observations of Mars from the Kuiper Airborne Observatory (KAO) have provided evidence for the presence of carbonates, sulfates, and hydrates. Using the optical properties of calcite and anhydrite, it was estimated that CO3's and SO4's constituted about 1 to 3 and 10 to 15 wt. percent, repectively of the materials composing the atmospheric dust. Using the derived value as an estimate of total CO3 abundance, and making an assumption that the CO3's were uniformly distributed within the Martian regolith, it was estimated that such a CO3 reservoir could contain roughly 2 to 5 bars of CO2. While the results indicate that several volatile-bearing materials are present on Mars, the observations from the KAO are inherently limited in their ability to determine the spatial distributions of these materials. However, previous spacecraft observations of Mars provide both the spectral coverage necessary to identify these materials, as well as the potential for investigating their spatial variability. This has prompted us to pursue a reinvestigation of the Mariner 6 and 7 infrared spectrometer and Mariner 9 infrared interferometer spectrometer observations. The former data have been recently made available in digital format and calibration of wavelengths and intensities are almost complete. Additionally, we are pursuing the derivation of optical constants of more appropriate carbonates and sulfates.
Spectra of Europa reveal a surface dominated by water-ice along with hydrated materials and minor amounts of SO2, CO2, and H2O2. Jovian magnetospheric ions (protons, sulfur, and oxygen) and electrons produce significant chemical modifications of the surface on time scales of a few years at micrometer depths. Our laboratory studies examine the formation and stability of radiation products in H2O-rich ices relevant to Europa. Infrared (IR) spectra of ices before and after irradiation reveal the radiation destruction of molecules and the formation of products at 86 - 132 K. In addition, spectra of ices during warming track thermal evolution due to chemical changes and sublimation processes. IR-identified radiation products in 86 - 132 K irradiated H2O + SO2 ices are the bisulfate ion, HSO4(-), sulfate ion, SO4(2-) and the hydronium ion, H3O(+). Warming results in the formation of a residual spectrum similar to liquid sulfuric acid, H2SO4, for H2O:SO2 ratios of 30:1, whereas hydrated sulfuric acid, H2SO4 4 H2O, forms for ratios of 30:1. Radiation products identified for irradiated H2O + H2S ices at 86 K are H2S2 and SO2. When irradiated at 110 and 132 K, ices with H2O:H2S ratios if either 3:1 or 30:1 show the formation of H2SO4 4 H2O on warming to 175 K. We have also examined the radiation stability of H2SO4. Addition of CO2 to H2O + SO2 ices results in the formation of CO3 at 2046 cm (sup -1) (4.89 m). This is the strongest band from a carbon-containing product in the mid-IR spectral region, and it is also seen when either pure CO2 or H2O + CO2 ice is irradiated. Experiments with CH4 added to H2O + SO2 + CO2 ices addressed the question of methane's use as a marker of methanogens in an irradiated ice environment. New results on the near-IR spectrum of pure H2O2 will be included in this presentation. Interpretations of near-IR water bands, with H2O2 present, will be discussed. Irradiations of H2O2 and H2O + H2O2 mixtures, to examine the possibility of O2 and O3 formation, are currently under investigation and new results will be discussed.