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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on CaGaSn by Materials Project

CaGaSn crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to six equivalent Sn atoms to form edge-sharing CaSn6 octahedra. All Ca–Sn bond lengths are 3.27 Å. In the second Ca site, Ca is bonded in a 12-coordinate geometry to six equivalent Ga and six equivalent Sn atoms. All Ca–Ga bond lengths are 3.01 Å. All Ca–Sn bond lengths are 3.55 Å. Ga is bonded in a 6-coordinate geometry to three equivalent Ca, one Ga, and three equivalent Sn atoms. The Ga–Ga bond length is 2.93 Å. All Ga–Sn bond lengths are 2.79 Å. Sn is bonded in a 6-coordinate geometry to six Ca and three equivalent Ga atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2Mg2B4O13 by Materials Project

Ca2Mg2B4O13 crystallizes in the orthorhombic Pbam 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 2.35–2.52 Å. There are three inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 14°. There are a spread of Mg–O bond distances ranging from 2.08–2.19 Å. In the second Mg site, Mg is bonded in a distorted hexagonal planar geometry to six O atoms. There are four shorter (2.03 Å) and two longer (2.10 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded to six O atoms to form edge-sharing MgO6 octahedra. There are four shorter (2.11 Å) and two longer (2.37 Å) Mg–O bond lengths. There are three inequivalent B sites. In the first B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.44–1.50 Å. In the second B site, B is bonded to four O atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.45–1.49 Å. In the third B site, B is bonded in a trigonal planar geometry to three O atoms. There are a spread of B–O bond distances ranging from 1.37–1.39 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to one Ca, two Mg, and one B atom. In the second O site, O is bonded in a bent 120 degrees geometry to two B atoms. In the third O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the fourth O site, O is bonded in a distorted single-bond geometry to two equivalent Ca and one B atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca and two B atoms. In the sixth O site, O is bonded in a distorted see-saw-like geometry to two equivalent Ca and two Mg atoms. In the seventh O site, O is bonded in a see-saw-like geometry to two equivalent Ca and two equivalent Mg atoms. In the eighth O site, O is bonded in a distorted single-bond geometry to two equivalent Ca and one B atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaBiO3 by Materials Project

CaBiO3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six equivalent CaO6 octahedra and corners with eight equivalent BiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 50–56°. There are four shorter (2.32 Å) and two longer (2.48 Å) Ca–O bond lengths. In the second Ca site, Ca is bonded to six O atoms to form CaO6 octahedra that share corners with six equivalent CaO6 octahedra and corners with eight equivalent BiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 50–56°. There are a spread of Ca–O bond distances ranging from 2.31–2.47 Å. Bi is bonded to four O atoms to form distorted BiO4 trigonal pyramids that share corners with eight CaO6 octahedra and corners with two equivalent BiO4 trigonal pyramids. The corner-sharing octahedra tilt angles range from 59–86°. There are a spread of Bi–O bond distances ranging from 2.11–2.40 Å. There are three inequivalent O sites. In the first O site, O is bonded to two Ca and two equivalent Bi atoms to form distorted corner-sharing OCa2Bi2 trigonal pyramids. In the second O site, O is bonded in a trigonal planar geometry to two Ca and one Bi atom. In the third O site, O is bonded in a trigonal planar geometry to two Ca and one Bi atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaH8(ClO6)2 by Materials Project

CaH8(O6Cl)2 crystallizes in the triclinic P-1 space group. The structure is one-dimensional and consists of one CaH8(O6Cl)2 ribbon oriented in the (0, -1, 1) direction. Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.63 Å. There are seven inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. In the second H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. In the third H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. In the fourth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the fifth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. In the sixth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. In the seventh H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.97 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a water-like geometry to one Ca and two H atoms. In the second O site, O is bonded in a water-like geometry to one Ca and two H atoms. The O–H bond length is 0.98 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.48 Å. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Ca and one Cl atom. The O–Cl bond length is 1.46 Å. In the sixth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Ca and one Cl atom. The O–Cl bond length is 1.46 Å. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Ca and one Cl atom. The O–Cl bond length is 1.46 Å. In the ninth O site, O is bonded in a distorted water-like geometry to one Ca and two H atoms. In the tenth O site, O is bonded in a distorted water-like geometry to one Ca and two H atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to one Ca and one Cl atom. The O–Cl bond length is 1.46 Å. In the twelfth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a tetrahedral geometry to four O atoms. In the second Cl site, Cl is bonded in a tetrahedral geometry to four O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaCa2Al2As2O11F4 by Materials Project

NaCa2Al2As2O11F4 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Na is bonded in a 4-coordinate geometry to three O and two equivalent F atoms. There are a spread of Na–O bond distances ranging from 2.46–2.72 Å. Both Na–F bond lengths are 2.19 Å. Ca is bonded in a 8-coordinate geometry to five O and three F atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.83 Å. There are a spread of Ca–F bond distances ranging from 2.38–2.41 Å. Al is bonded to four O and two F atoms to form AlO4F2 octahedra that share a cornercorner with one AlO4F2 octahedra and corners with two AsO4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are a spread of Al–O bond distances ranging from 1.87–1.96 Å. There is one shorter (1.80 Å) and one longer (1.92 Å) Al–F bond length. There are two inequivalent As sites. In the first As site, As is bonded to four O atoms to form AsO4 tetrahedra that share corners with two equivalent AlO4F2 octahedra. The corner-sharing octahedral tilt angles are 52°. There is three shorter (1.71 Å) and one longer (1.76 Å) As–O bond length. In the second As site, As is bonded to four O atoms to form AsO4 tetrahedra that share corners with two equivalent AlO4F2 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of As–O bond distances ranging from 1.69–1.74 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a water-like geometry to one Na and one As atom. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Al atoms. In the third O site, O is bonded in a distorted single-bond geometry to one Ca and one Al atom. In the fourth O site, O is bonded in a 4-coordinate geometry to one Na, two equivalent Ca, and one As atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to one Al and one As atom. In the sixth O site, O is bonded in a 4-coordinate geometry to one Na, two equivalent Ca, and one As atom. In the seventh O site, O is bonded in a 1-coordinate geometry to two equivalent Ca and one As atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one As atom. There are two inequivalent F sites. In the first F site, F is bonded in a 3-coordinate geometry to one Na, one Ca, and one Al atom. In the second F site, F is bonded in a distorted trigonal planar geometry to two equivalent Ca and one Al atom.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Thermodynamics of calcium binding to heparin: Implications of solvation and water structuring for polysaccharide biofunctions

Heparan sulfates are found in all animal tissues and have essential roles in living systems. This family of biomacromolecules modulates binding to calcium ions (Ca 2+ ) in low free energy reactions that influence biochemical processes from cell signaling and anticoagulant efficacy to biomineralization. Despite their ubiquity, the thermodynamic basis for how heparans and similarly functionalized biomolecules regulate Ca 2+ interactions is not yet established. Using heparosan (Control) and heparins with different positions of sulfate groups, we quantify how SO 3 − and COO − content and SO 3 − position modulate Ca 2+ binding by isothermal titration calorimetry. The free energy of all heparin-Ca2+ interactions (ΔG rxn ) is dominated by entropic contributions due to favorable water release from polar, hydrophilic groups. Heparin with both sulfate esters (O-SO 3 − ) and sulfamides (N-SO 3 − ) has the strongest binding to Ca 2+ compared to heparosan and to heparin with only O-SO 3 − groups (~3X). By linking Ca 2+ binding thermodynamics to measurements of the interfacial energy for calcite (CaCO 3 ) crystallization onto polysaccharides, we show molecule-specific differences in nucleation rate can be explained by differences in water structuring during Ca 2+ interactions. A large entropic term (-TΔS rxn ) upon Ca 2+ –polysaccharide binding correlates with high interfacial energy to CaCO 3 nucleation. Combining our measurements with literature values indicates many Ca 2+ –polysaccharide interactions have a shared thermodynamic signature. The resulting enthalpy–entropy compensation relationship suggests these interactions are generally dominated by water restructuring involving few conformational changes, distinct from Ca 2+ –protein binding. Our findings quantify the thermodynamic origins of heparin-specific interactions with Ca 2+ and demonstrate the contributions of solvation and functional group position during biomacromolecule-mediated ion regulation.

15 GEOTHERMAL ENERGY↗
DOE OSTI2025

Calcium is associated with specific soil organic carbon decomposition products at Blodgett Forest Research Center, Georgetown, California as analysed with scanning transmission X-ray microscopy carbon near-edge X-ray absorption fine structure spectroscopy

This data is from the paper calcium is associated with specific soil organic carbon decomposition products, published in SOIL. DOI: https://doi.org/10.5194/soil-11-381-2025, 2025.This file contains CSVs with spectral data and bulk soil data and there is no specific program required to open this data. The data includes Scanning transmission X-ray microscopy carbon near-edge X-ray absorption fine structure spectroscopy. data from the measurement of samples from the Whole-soil Warming project, run by the Belowground Biogeochemistry team at Blodgett Forest Research Center, Georgetown, California run by the University of California, Berkeley. It also includes bulk soil chemical properties. The University of California's Blodgett Forest Research Station (Forest) is situated in the Sierra Nevada foothills (1370 m a.s.l.) near Georgetown, California. The samples were collected from here: 38.912013, -120.661469, https://maps.app.goo.gl/291bCJ1zVqUhgktz6. The Forest soils were characterised as Alfisols, which are equivalent to Dystric Cambisols (IUSS Working Group WRB, 2015), and formed in granitic parent materials, in a temperate climate, under thinned, mixed-coniferous forest (Fig. S3; Gaudinski et al., 2009). With these analyses we aimed to answer the question, is calcium associated with a specific type of organic matter enriched in aromatic and phenolic carbon at the microscale in samples from Blodgett Forest Research Center? and how does this specific type of carbon respond to experiments targetted at removing and adding calcium to the soils, specifically cation exchange and incubation after calcium addition? Abstract from the paper can be found below: Calcium (Ca) may contribute to the preservation of soil organic carbon (SOC) in more ecosystems than previously thought. Here we provide evidence that Ca is co-located with SOC compounds that are enriched in aromatic and phenolic groups, across different acidic soil-types and locations with different ecosystem properties, differing in terms of climate, parent material, soil type, and vegetation. In turn, this co-localised fraction of Ca-SOC is removed through cation-exchange, and the association is then only re-established during decomposition in the presence of Ca (Ca addition incubation). Thus, highlighting a causative link between decomposition and the co-location of Ca with a characteristic fraction of SOC. Decomposition increases the relative proportion of negatively charged functional groups, which can increase the propensity for the association between SOC and Ca, and in turn, this association inhibits dissolved organic carbon export or further decomposition. We propose that this mechanism could be driven by Ca hotspots on the microscale shifting local decomposition processes and thereby explaining the colocation of Ca with SOC of a specific composition across different acidic soil environments. Incorporating this biogeochemical process into Earth System Models could improve our understanding, predictions, and management of carbon dynamics in soils, and account for their response to Ca-rich amendments.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Calcium is associated with specific soil organic carbon decomposition products

Abstract. Calcium (Ca) may contribute to the preservation of soil organic carbon (SOC) in more ecosystems than previously thought. Here, we provide evidence that Ca is co-located with SOC compounds that are enriched in aromatic and phenolic groups, across different acidic soil types and locations with different ecosystem properties, differing in terms of climate, parent material, soil type, and vegetation. In turn, this co-localised fraction of Ca–SOC is removed through cation exchange, and the association is then only re-established during decomposition in the presence of Ca (Ca addition incubation). Thus, this highlights a causative link between decomposition and the co-location of Ca with a characteristic fraction of SOC. Decomposition increases the relative proportion of negatively charged functional groups, which can increase the propensity for the association between SOC and Ca; in turn, this association can inhibit dissolved organic carbon export or further decomposition. We propose that this mechanism could be driven by Ca hotspots at the microscale shifting local decomposition processes and thereby explaining the co-location of Ca with SOC of a specific composition across different acidic soil environments. Incorporating this biogeochemical process into Earth system models could improve our understanding, predictions, and management of carbon dynamics in soils, as well as accounting for their response to Ca-rich amendments.

Rowley, Mike C. (ORCID:0000000224407855)↗
NASA NTRS1996

Calcium Balance in Mature Rats Exposed to a Space Flight Model

Depressed intestinal calcium absorption (Ca abs.) and lower circulating 1,25-dihydroxyvitamin D (1,25-D) are associated with less positive calcium balance in young 200 g rats exposed to skeletal unloading by hind-limb suspension than controls (C) . To determine the effect of the space flight model on calcium balance in mature rats, we exposed 6 mo. old males weighing 492 +/- 12g to the model for 4 weeks (S) and compared Ca in the diet, urine, feces and 1,25-D in S and C. Rats were fed diets containing sufficient Ca to satisfy metabolic needs, but not to cause deficiency (0.1%). At the end of 4 weeks, there was a 5 percent weight loss in S, but not in C; and no differences in dietary, urine (UCa) or fecal Ca (FCa) in S and C. Net Ca abs. (0.1 vs 2.7 %), 1,25-D (50 +/- 16 vs 47 +/- 14 pg/ml) and Ca balances (-1.8 +/- 4 vs -1.0 +/- 2.9 mg/d) were similar in C and S. UCa loss was added to the model by inducing calciuria with 8% salt diets (HiNa). A 4-fold increase in UCa in C and S was transiently higher in S than C after 1 week. After 4 weeks, loss in BW was greater in S than C, Ca abs was higher in C than S (32 +/- 10 vs 3.5 +/- 16%, p less than .05), 1,25-D greater in S than C (98 +/- 15 vs 79 +/- 14 pg/ml p less than .05) and Ca balance less in S than C (-5.2 +/- 4 vs -1.7 +/- 2 mg/d, p less than .05). Ca balance in the mature rat is unaffected by the space flight model unless calciuria intervenes and reveals the failure of the intestine to enhance Ca abs. and compensate for UCa loss.

Navidi, Meena↗
NASA NTRSDate not supplied

Setting the Bar for the Replacement of the Probability of Collision Metric

To date, satellite conjunction assessment (CA) risk analysis has largely embraced the probability of collision (Pc) as the omnibus metric to evaluate collision likelihood, and its use in such assessments has mostly been straightforward: at the point at which a conjunction mitigation decision is required, the calculated Pc is compared to a threshold; and if the calculated Pc exceeds that threshold, then a mitigation action is warranted. With only minor variation, this approach is employed by major CA risk assessment centers (e.g., NASA, EUSST, CNES, JAXA) and is advanced as the preferred method in the published CA best practices handbooks. Despite this near unanimity of operational practice, there is a major strain of secondary literature critical of the Pc and willing to propose alternatives. Alfano (2005) pointed out the ability of the Pc to underrepresent the risk in certain situations and counselled a maximum Pc construct. Carpenter (2017, 2019) reiterated this criticism and proposed using instead a confidence interval on the miss distance. Balch et al. (2019) identified what they argued was a defect in the entire Bayesian Pc construct and believed that the use of a more conservative methodology based on covariance ellipsoid overlap was necessary. Delande (2022) introduced the framework of collision “plausibility” to the risk assessment process and sketched out how this might be used operationally. Elkantassi (2022) published a full development of the miss distance confidence interval approach and applied it to several worked examples. While these different approaches to collision risk assessment do differ in their details, they all converge on two central points: first, the Pc’s failure to give an adequate expression of the risk in dilution region situations is a fatal flaw; and second, a conjunction should be presumed risky and in need of mitigation until the evidence of the situation can establish otherwise. These criticisms, if correct, would counsel a number of modifications to current CA operational practice; as such, they force a re-examination of fundamental aspects of the CA problem, including the following: 1. Is the CA risk assessment a probability problem, a statistics problem, or something else? 2. If it is a statistics problem, does it lend itself naturally to a hypothesis test construction? 3. If it can be construed as a hypothesis test, what form should the null hypothesis take, to wit: what constraints exist on the choice of the null hypothesis, what selections are in best alignment with all of the attendant parameters of the problem, and what is implied philosophically by different choices? 4. What are the implications of using the different proposed risk assessment parameters for CA? This question should be answered both in determining how frequently the dilution region situation cited by the critics of the Pc actually appears in an operationally significant manner and the missed detection and false alarm rates of all of the proposed risk assessment metrics, compared both to the Pc and to each other. This paper explores and offers preliminary answers to the above questions, presenting a researched treatment of the philosophical nature of the CA problem and the null hypothesis choice that achieves the greatest consistency with all of the different aspects of operational CA conduct. It then profiles all of the different proposed risk assessment metrics enumerated in the earlier paragraph against an extremely large database of conjunction events at both the 550km and 700km altitudes. The combination of the philosophical exploration of the CA problem and the results of the profiling activity articulates what a risk assessment metric will need to demonstrate, in terms of both innate construction and performance, in order to be a true competitor to the Pc.

conjunction assessment↗
DOE OSTI2020

Materials Data on Ca5Ge3 by Materials Project

Ca5Ge3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a square co-planar geometry to four equivalent Ge atoms. All Ca–Ge bond lengths are 3.09 Å. In the second Ca site, Ca is bonded to five Ge atoms to form a mixture of distorted corner, edge, and face-sharing CaGe5 trigonal bipyramids. There are a spread of Ca–Ge bond distances ranging from 3.05–3.28 Å. There are two inequivalent Ge sites. In the first Ge site, Ge is bonded in a 8-coordinate geometry to eight equivalent Ca atoms. In the second Ge site, Ge is bonded in a 9-coordinate geometry to eight Ca and one Ge atom. The Ge–Ge bond length is 2.59 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca5Zn3 by Materials Project

Ca5Zn3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a square co-planar geometry to four equivalent Zn atoms. All Ca–Zn bond lengths are 3.16 Å. In the second Ca site, Ca is bonded to five Zn atoms to form a mixture of distorted edge, face, and corner-sharing CaZn5 trigonal bipyramids. There are a spread of Ca–Zn bond distances ranging from 3.22–3.33 Å. There are two inequivalent Zn sites. In the first Zn site, Zn is bonded in a 8-coordinate geometry to eight equivalent Ca atoms. In the second Zn site, Zn is bonded in a 9-coordinate geometry to eight Ca and one Zn atom. The Zn–Zn bond length is 2.62 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CaTeO3 by Materials Project

CaTeO3 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, edges with two equivalent CaO7 hexagonal pyramids, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 51°. There are a spread of Ca–O bond distances ranging from 2.32–2.50 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share a cornercorner with one CaO7 hexagonal pyramid, corners with two CaO6 octahedra, an edgeedge with one CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 51–65°. There are a spread of Ca–O bond distances ranging from 2.33–2.54 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.41–2.47 Å. In the fourth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share a cornercorner with one CaO7 pentagonal bipyramid, an edgeedge with one CaO7 hexagonal pyramid, edges with two CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. There are a spread of Ca–O bond distances ranging from 2.33–2.63 Å. In the fifth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO7 hexagonal pyramid, a cornercorner with one CaO6 octahedra, and edges with two CaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 65°. There are a spread of Ca–O bond distances ranging from 2.31–2.44 Å. In the sixth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share an edgeedge with one CaO6 octahedra and edges with two CaO7 pentagonal bipyramids. There are a spread of Ca–O bond distances ranging from 2.32–2.59 Å. In the seventh Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 hexagonal pyramids that share corners with two CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, an edgeedge with one CaO7 hexagonal pyramid, edges with two equivalent CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 47–62°. There are a spread of Ca–O bond distances ranging from 2.40–2.53 Å. In the eighth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share a cornercorner with one CaO7 hexagonal pyramid, a cornercorner with one CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, an edgeedge with one CaO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 74°. There are a spread of Ca–O bond distances ranging from 2.33–2.69 Å. In the ninth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.38–2.95 Å. There are nine inequivalent Te4+ sites. In the first Te4+ site, Te4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.88 Å) and one longer (1.91 Å) Te–O bond length. In the second Te4+ site, Te4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–2.71 Å. In the third Te4+ site, Te4+ is bonded in a 5-coordinate geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.84 Å. In the fourth Te4+ site, Te4+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Te–O bond distances ranging from 1.90–2.49 Å. In the fifth Te4+ site, Te4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.88–1.90 Å. In the sixth Te4+ site, Te4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.87–1.89 Å. In the seventh Te4+ site, Te4+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–2.77 Å. In the eighth Te4+ site, Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There is one shorter (1.89 Å) and two longer (1.92 Å) Te–O bond length. In the ninth Te4+ site, Te4+ is bonded in a distorted T-shaped geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.89–1.92 Å. There are twenty-seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+ and two Te4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Te4+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one Te4+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the fifth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the sixth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te trigonal pyramids. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the eighth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te trigonal pyramids. In the ninth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ca2+ and one Te4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to three Te4+ atoms. In the twelfth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Te4+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca2+ and one Te4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two Te4+ atoms. In the seventeenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+ and two Te4+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+ and one Te4+ atom. In the nineteenth O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the twentieth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Ca2+ and one Te4+ atom. In the twenty-first O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the twenty-second O2- site, O2- is bonded to three Ca2+ and one Te4+ atom to form a mixture of distorted corner and edge-sharing OCa3Te tetrahedra. In the twenty-third O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the twenty-fourth O2- site, O2- is bonded in a trigonal planar geometry to two Ca2+ and one Te4+ atom. In the twenty-fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom. In the twenty-sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca2+ and one Te4+ atom. In the twenty-seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ca2+ and one Te4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca5Au3 by Materials Project

Ca5Au3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to five Au atoms to form a mixture of distorted face, edge, and corner-sharing CaAu5 trigonal bipyramids. There are a spread of Ca–Au bond distances ranging from 3.07–3.31 Å. In the second Ca site, Ca is bonded in a distorted square co-planar geometry to six Au atoms. There are four shorter (3.09 Å) and two longer (3.66 Å) Ca–Au bond lengths. There are two inequivalent Au sites. In the first Au site, Au is bonded in a 10-coordinate geometry to ten Ca atoms. In the second Au site, Au is bonded in a 9-coordinate geometry to eight Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca5Hg3 by Materials Project

Ca5Hg3 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a distorted square co-planar geometry to six Hg atoms. There are four shorter (3.21 Å) and two longer (3.71 Å) Ca–Hg bond lengths. In the second Ca site, Ca is bonded to five Hg atoms to form a mixture of distorted edge, corner, and face-sharing CaHg5 trigonal bipyramids. There are a spread of Ca–Hg bond distances ranging from 3.21–3.44 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a 10-coordinate geometry to ten Ca atoms. In the second Hg site, Hg is bonded in a 8-coordinate geometry to eight Ca atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca5Ag3 by Materials Project

Ag3Ca5 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to five Ag atoms to form a mixture of distorted edge, corner, and face-sharing CaAg5 trigonal bipyramids. There are a spread of Ca–Ag bond distances ranging from 3.19–3.37 Å. In the second Ca site, Ca is bonded in a distorted square co-planar geometry to six Ag atoms. There are four shorter (3.16 Å) and two longer (3.74 Å) Ca–Ag bond lengths. There are two inequivalent Ag sites. In the first Ag site, Ag is bonded in a 10-coordinate geometry to ten Ca atoms. In the second Ag site, Ag is bonded in a 9-coordinate geometry to eight Ca and one Ag atom. The Ag–Ag bond length is 2.88 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3(AsO4)2 by Materials Project

Ca3(AsO4)2 crystallizes in the trigonal R3 space group. The structure is three-dimensional. there are nine inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six AsO4 tetrahedra and edges with three equivalent CaO7 pentagonal bipyramids. There are three shorter (2.29 Å) and three longer (2.32 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent CaO7 pentagonal bipyramids, corners with five AsO4 tetrahedra, an edgeedge with one CaO6 octahedra, and an edgeedge with one AsO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.33–2.65 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.93 Å. In the fourth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share corners with two equivalent CaO7 pentagonal bipyramids, corners with five AsO4 tetrahedra, an edgeedge with one CaO6 octahedra, and an edgeedge with one AsO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.34–2.54 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.91 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.43–2.99 Å. In the seventh Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.41 Å) and three longer (2.71 Å) Ca–O bond lengths. In the eighth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.91 Å. In the ninth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with six AsO4 tetrahedra and edges with three equivalent CaO7 pentagonal bipyramids. There are three shorter (2.31 Å) and three longer (2.34 Å) Ca–O bond lengths. There are six inequivalent As5+ sites. In the first As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent CaO7 pentagonal bipyramids. There is three shorter (1.72 Å) and one longer (1.74 Å) As–O bond length. In the second As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one CaO6 octahedra and corners with three CaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are a spread of As–O bond distances ranging from 1.71–1.73 Å. In the third As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one CaO6 octahedra and corners with three CaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There is two shorter (1.71 Å) and two longer (1.72 Å) As–O bond length. In the fourth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with three equivalent CaO7 pentagonal bipyramids. There is one shorter (1.70 Å) and three longer (1.74 Å) As–O bond length. In the fifth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 46°. There are a spread of As–O bond distances ranging from 1.70–1.74 Å. In the sixth As5+ site, As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share a cornercorner with one CaO6 octahedra, a cornercorner with one CaO7 pentagonal bipyramid, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 56°. There is two shorter (1.71 Å) and two longer (1.74 Å) As–O bond length. There are twenty inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Ca2+ and one As5+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three Ca2+ and one As5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one As5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one As5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one As5+ atom. In the seventh O2- site, O2- is bonded in a distorted tetrahedral geometry to three Ca2+ and one As5+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three equivalent Ca2+ and one As5+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one As5+ atom. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one As5+ atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one As5+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one As5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one As5+ atom. In the nineteenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one As5+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one As5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca4Nb2O9 by Materials Project

Ca4Nb2O9 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 31–44°. There are a spread of Ca–O bond distances ranging from 2.28–2.35 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.78 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.60 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.83 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.87 Å. In the sixth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 41–43°. There are a spread of Ca–O bond distances ranging from 2.30–2.36 Å. In the seventh Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six NbO6 octahedra. The corner-sharing octahedra tilt angles range from 34–47°. There are a spread of Ca–O bond distances ranging from 2.28–2.33 Å. In the eighth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.84 Å. In the ninth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.86 Å. There are five inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 28–42°. There are a spread of Nb–O bond distances ranging from 1.91–2.28 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share a cornercorner with one NbO6 octahedra and corners with five CaO6 octahedra. The corner-sharing octahedra tilt angles range from 31–47°. There are a spread of Nb–O bond distances ranging from 1.91–2.46 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with three CaO6 octahedra and corners with three equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 28–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.36 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with four CaO6 octahedra. The corner-sharing octahedra tilt angles range from 31–44°. There are a spread of Nb–O bond distances ranging from 1.99–2.13 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with four CaO6 octahedra. The corner-sharing octahedra tilt angles range from 28–38°. There are a spread of Nb–O bond distances ranging from 1.98–2.11 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Nb5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Nb5+ atom. In the fourth O2- site, O2- is bonded to two Ca2+ and two Nb5+ atoms to form distorted OCa2Nb2 trigonal pyramids that share a cornercorner with one OCa3Nb tetrahedra, corners with two OCa2Nb2 trigonal pyramids, and an edgeedge with one OCa3Nb trigonal pyramid. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Nb5+ atom. In the seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to three Ca2+ and one Nb5+ atom. In the eighth O2- site, O2- is bonded to three Ca2+ and one Nb5+ atom to form distorted OCa3Nb trigonal pyramids that share a cornercorner with one OCa3Nb tetrahedra, corners with three OCa2Nb2 trigonal pyramids, and an edgeedge with one OCa2Nb2 trigonal pyramid. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Nb5+ atom. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Nb5+ atom. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Nb5+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Nb5+ atom. In the thirteenth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Nb5+ atom. In the fourteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Ca2+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Nb5+ atom. In the sixteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded to three Ca2+ and one Nb5+ atom to form distorted OCa3Nb tetrahedra that share a cornercorner with one OCa3Nb tetrahedra and corners with two OCa2Nb2 trigonal pyramids.

36 MATERIALS SCIENCE↗