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All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Data for Catalyst and Reactor Design Considerations for Selective Production of Acids by Oxidative Cleavage of Alkenes with H2O2

Oxidative cleavage of alkenes and unsaturated fatty acids with hydrogen peroxide gives an efficient and sustainable process to obtain mono- and di-acids for polymers and lubricants with fewer safety risks and less environmental impact than processes that utilize ozone or other inorganic oxidizers (e.g., permanganate, dichromate, etc.). Guided by insight into the mechanisms for competing reaction pathways (i.e., epoxidation of alkene on W–(η2-O2) complexes vs. H2O2 decomposition) and the apparent kinetics derived from kinetic experiments, here, we postulate that W-based heterogeneous catalysts can provide high performance and stable operations at low H2O2 concentrations. Semi-batch reactors with continuous introduction of H2O2 solutions offer the means to maintain low H2O2 concentrations while providing sufficient quantities of H2O2 to satisfy the reaction stoichiometry. We derived simple kinetic model equations for the epoxidation, ring-opening, oxidative cleavage, and oxidation steps and fit theses equations to batch experimental data to obtain kinetic parameters. This kinetic model describes the concentration profiles of reactant, oxidant, and products well as shown by agreement with experimental data. Further predictions of the optimal H2O2 feed rate for semi-batch operation utilized by the proposed rate expressions and the reactor design equations suggest that low H2O2 feed rate increases selectivity towards oxidative cleavage products and selective use of H2O2 for oxidative cleavage pathway. Comparisons of oxidative cleavage of 4-octene in batch and semi-batch reactors show that semi-batch reactors with optimized molar feed rates of H2O2 increased oxidative cleavage product selectivities (76% to 99%; with an increase in butyric acid selectivity from 1% to 55%) and H2O2 selectivity (3% to 30%). In addition, semi-batch reaction conditions used avoid H2O2-mediated dissolution of W-atoms from the catalyst. Analysis of these findings suggest that solid oxide catalysts will be effective for continuous oxidative cleavage reactions if deployed within fixed-bed reactors that allow for distributed introduction of reactants and therefore low in situ concentrations of H2O2.

Catalysis↗
DOE OSTI2022

Effects of physical, chemical, and biological ageing on the mineralization of pine wood biochar by a Streptomyces isolate

If biochar is to be used for carbon (C) management, we must understand how weathering or ageing affects biochar C mineralization. Here, we incubated aged and unaged eastern white pine wood biochar produced at 350 and 550°C with a Streptomyces isolate, a putative biochar-decomposing microbe. Ageing was accelerated via three different processes, namely, (a) physical ageing–subjecting biochar to alternating freeze-thaw and wet-dry cycles, (b) chemical ageing–treating biochar with concentrated hydrogen peroxide and (c) biological ageing–incubating biochar in the presence of nutrients and microorganisms. Elemental composition and surface chemistry (Fourier Transform Infrared spectroscopy) of biochar samples were compared before and after ageing. Biochar C mineralization between ageing treatments was significantly different in the case of 350°C biochar ( p value = 0.03). Among the 350°C biochars, physical ageing resulted in the greatest increase (by 103%) in biochar C mineralization ( p value = 0.05). However, in the case of 550°C biochar, ageing did not result in a significant change in biochar C mineralization ( p value = 0.40). Biochar C mineralization was positively correlated with an increase in O/C ratio post-ageing ( r s = 0.86, p value = 0.01). In the case of 350°C biochar, surface oxidation during ageing enhanced biochar degradation by the isolate. For 550°C biochar, however, ageing did not significantly increase biochar C mineralization, likely due to high condensed aromatic C content and lower surface oxidation during ageing. The results from our study suggest that low temperature aged biochar is more susceptible to biological degradation by soil microbes. These findings have implications for the use of biochar for long term C storage in soils.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Materials Data on O2 by Materials Project

O2 is alpha oxygen-like structured and crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of eight hydrogen peroxide molecules. O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H11O8 by Materials Project

(H2O)2(H2O2)3(H3O2)4 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one hydrogen peroxide hydrate molecule, one water molecule, and two water water molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si6O13 by Materials Project

(SiO2)12O2 is Low Tridymite-like structured and crystallizes in the hexagonal P6/mcc space group. The structure is three-dimensional and consists of two hydrogen peroxide molecules and one SiO2 framework. In the SiO2 framework, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There is three shorter (1.62 Å) and one longer (1.63 Å) Si–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the third O site, O is bonded in a linear geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgH16C4S4N2(O4F3)4 by Materials Project

MgH4S4(NO4)2(CHF3)2(CF2)2(H2O)4(HF)2(O2)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four difluoromethane molecules, four fluoroform molecules, four hydrofluoric acid molecules, four hydrogen peroxide molecules, eight water molecules, and two MgH4S4(NO4)2 clusters. In each MgH4S4(NO4)2 cluster, Mg2+ is bonded in a distorted linear geometry to two equivalent O2- atoms. Both Mg–O bond lengths are 1.91 Å. N5+ is bonded in a distorted trigonal planar geometry to one H1+, one S, and one O2- atom. The N–H bond length is 1.09 Å. The N–S bond length is 1.69 Å. The N–O bond length is 1.24 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N5+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one S atom. The H–S bond length is 1.34 Å. There are two inequivalent S sites. In the first S site, S is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.49–1.57 Å. In the second S site, S is bonded in a 2-coordinate geometry to one N5+, one H1+, and one O2- atom. The S–O bond length is 2.41 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one S atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two S atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one S atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on O2 by Materials Project

O2 is Cubic alpha N2-like structured and crystallizes in the orthorhombic Fmmm space group. The structure is zero-dimensional and consists of four hydrogen peroxide molecules. O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on O2 by Materials Project

O2 is beta oxygen structured and crystallizes in the trigonal R-3m space group. The structure is zero-dimensional and consists of three hydrogen peroxide molecules. O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on O2 by Materials Project

O2 is alpha oxygen structured and crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of two hydrogen peroxide molecules. O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.23 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SNClO4 by Materials Project

NClSO2O2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four chloramine molecules, four hydrogen peroxide molecules, and four sulfur dioxide molecules.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si6O13 by Materials Project

(Si4O7)6(O2)5 crystallizes in the monoclinic Pm space group. The structure is three-dimensional and consists of four hydrogen peroxide molecules, two water molecules, and one Si4O7 framework. In the Si4O7 framework, there are twelve inequivalent Si sites. In the first Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There is one shorter (1.62 Å) and three longer (1.63 Å) Si–O bond length. In the third Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the fourth Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.73 Å. In the fifth Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the sixth Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.64 Å. In the seventh Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There is two shorter (1.62 Å) and two longer (1.63 Å) Si–O bond length. In the eighth Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Si–O bond distances ranging from 1.64–1.66 Å. In the ninth Si site, Si is bonded to four O atoms to form corner-sharing SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.63 Å. In the tenth Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the eleventh Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There is two shorter (1.64 Å) and one longer (1.65 Å) Si–O bond length. In the twelfth Si site, Si is bonded in a trigonal non-coplanar geometry to three O atoms. There is two shorter (1.64 Å) and one longer (1.65 Å) Si–O bond length. There are twenty-four inequivalent O sites. In the first O site, O is bonded in a linear geometry to two Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the sixth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the seventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent Si and one O atom. The O–O bond length is 1.51 Å. In the ninth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the tenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the eleventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twelfth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the thirteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fourteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the sixteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the seventeenth O site, O is bonded in a single-bond geometry to one O atom. In the eighteenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the nineteenth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twentieth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twenty-first O site, O is bonded in a linear geometry to two equivalent Si atoms. In the twenty-second O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twenty-third O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twenty-fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H2O by Materials Project

H2O crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of three hydrogen molecules, one hydrogen peroxide hydrate molecule, nine water molecules, one water molecule, and one water molecule.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaCo2H3(SeO5)2 by Materials Project

Na(SeO2)2Co2HO4H2O2 crystallizes in the monoclinic Cm space group. The structure is one-dimensional and consists of two hydrogen molecules; two hydrogen peroxide molecules; two Co2HO4 ribbons oriented in the (0, 1, 0) direction; and two Na(SeO2)2 ribbons oriented in the (0, 1, 0) direction. In each Co2HO4 ribbon, Co2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Co–O bond distances ranging from 1.80–1.99 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Co2+ and one H1+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Co2+ and one O2- atom. The O–O bond length is 1.48 Å. In the third O2- site, O2- is bonded in an L-shaped geometry to two equivalent Co2+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Co2+ and one O2- atom. In each Na(SeO2)2 ribbon, Na1+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.29 Å) and two longer (2.37 Å) Na–O bond lengths. There are two inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded in a water-like geometry to two equivalent O2- atoms. Both Se–O bond lengths are 1.65 Å. In the second Se6+ site, Se6+ is bonded in a water-like geometry to two equivalent O2- atoms. Both Se–O bond lengths are 1.68 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Na1+ and one Se6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Na1+ and one Se6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CdH20C2S2(NO2)6 by Materials Project

Cd(NH)2(CNH2)2(H2)4(NO)2(H3SO4)2O2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ac1nrvfo molecules, four hydrogen molecules, one hydrogen peroxide molecule, two methanimine molecules, two nitroxyl molecules, and one Cd(NH)2 cluster. In the Cd(NH)2 cluster, Cd2+ is bonded in a distorted linear geometry to two equivalent N+0.33- atoms. Both Cd–N bond lengths are 2.09 Å. N+0.33- is bonded in a distorted bent 120 degrees geometry to one Cd2+ and one H1+ atom. The N–H bond length is 1.04 Å. H1+ is bonded in a single-bond geometry to one N+0.33- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlH18(BrO6)3 by Materials Project

(H2)2(AlH8O7Br)2(HO2)4(H2O)4H2O2(HO2Br)2(O2)2(Br)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two hydrobromic acid molecules, two hydrogen molecules, two hydrogen peroxide molecules, two hydroxyperoxide molecules, two hypobromous acid;hydrate molecules, four water molecules, two water molecules, and two AlH8O7Br clusters. In each AlH8O7Br cluster, Al3+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of Al–O bond distances ranging from 1.74–1.99 Å. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.66 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the eighth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.05 Å) and one longer (1.41 Å) H–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Br5+ atom. The O–Br bond length is 1.81 Å. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Al3+ and two H1+ atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one Al3+ atom. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to three H1+ atoms. In the fifth O2- site, O2- is bonded in a distorted water-like geometry to three H1+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Al3+ and two H1+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Al3+ and one Br5+ atom. The O–Br bond length is 2.07 Å. Br5+ is bonded in a distorted linear geometry to two O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgH12SO10 by Materials Project

(MgH11SO8)2H2(O2)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of four hydrogen molecules; eight hydrogen peroxide molecules; and two MgH11SO8 sheets oriented in the (-1, 0, 2) direction. In each MgH11SO8 sheet, there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted octahedral geometry to two equivalent H1+ and four O2- atoms. Both Mg–H bond lengths are 2.34 Å. There are two shorter (2.01 Å) and two longer (2.06 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.98 Å) and two longer (1.99 Å) Mg–O bond length. There are eleven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.67 Å) H–O bond length. In the third H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.72 Å) H–O bond length. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one Mg2+ atom. In the sixth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.06 Å) and one longer (1.44 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the eighth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.56 Å) H–O bond length. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. S6+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of S–O bond distances ranging from 1.52–1.55 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Mg2+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S6+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to three H1+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two H1+ and one S6+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one S6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuO2 by Materials Project

CuO2 is Cyanogen Chloride-derived structured and crystallizes in the orthorhombic Pmmm space group. The structure is one-dimensional and consists of one hydrogen peroxide molecule and one Cu ribbon oriented in the (1, 0, 0) direction. In the Cu ribbon, Cu is bonded in a distorted linear geometry to two equivalent Cu atoms. Both Cu–Cu bond lengths are 2.42 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BaZn2H16O11 by Materials Project

BaZn2H16O9O2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of four hydrogen peroxide molecules and one BaZn2H16O9 framework. In the BaZn2H16O9 framework, Ba2+ is bonded in a 6-coordinate geometry to four H1+ and six O2- atoms. There are a spread of Ba–H bond distances ranging from 2.65–3.00 Å. There are a spread of Ba–O bond distances ranging from 2.60–3.21 Å. There are two inequivalent Zn2+ sites. In the first Zn2+ site, Zn2+ is bonded to three H1+ and one O2- atom to form corner-sharing ZnH3O tetrahedra. There are a spread of Zn–H bond distances ranging from 1.60–1.77 Å. The Zn–O bond length is 2.25 Å. In the second Zn2+ site, Zn2+ is bonded to one H1+ and three O2- atoms to form corner-sharing ZnHO3 tetrahedra. The Zn–H bond length is 1.67 Å. There are a spread of Zn–O bond distances ranging from 1.98–2.01 Å. There are sixteen inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted bent 150 degrees geometry to one Ba2+ and one Zn2+ atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one Ba2+ and one H1+ atom. The H–H bond length is 0.75 Å. In the fourth H1+ site, H1+ is bonded in a distorted single-bond geometry to one Ba2+ and one Zn2+ atom. In the fifth H1+ site, H1+ is bonded in a bent 120 degrees geometry to two Zn2+ atoms. In the sixth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.13 Å) and one longer (1.32 Å) H–O bond length. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the ninth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.06 Å) and one longer (1.45 Å) H–O bond length. In the tenth H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.09 Å) and one longer (1.45 Å) H–O bond length. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the thirteenth H1+ site, H1+ is bonded in a distorted bent 150 degrees geometry to two O2- atoms. There is one shorter (1.02 Å) and one longer (1.63 Å) H–O bond length. In the fourteenth H1+ site, H1+ is bonded in a single-bond geometry to one Ba2+ and one H1+ atom. In the fifteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the sixteenth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Ba2+ and one H1+ atom. In the second O2- site, O2- is bonded in a distorted tetrahedral geometry to one Zn2+ and three H1+ atoms. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Ba2+ and one O2- atom. The O–O bond length is 1.27 Å. In the fourth O2- site, O2- is bonded in a distorted water-like geometry to one Zn2+ and two H1+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Zn2+ and two H1+ atoms. In the sixth O2- site, O2- is bonded in a single-bond geometry to one Ba2+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a water-like geometry to one Ba2+ and two H1+ atoms. In the eighth O2- site, O2- is bonded in a distorted water-like geometry to one Ba2+ and two H1+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Zn2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗