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DOE OSTI2020

Materials Data on TiN2 by Materials Project

TiN2 crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. there are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded in a distorted body-centered cubic geometry to eight N2- atoms. All Ti–N bond lengths are 2.20 Å. In the second Ti4+ site, Ti4+ is bonded in a distorted body-centered cubic geometry to eight N2- atoms. All Ti–N bond lengths are 2.20 Å. There are five inequivalent N2- sites. In the first N2- site, N2- is bonded in a 5-coordinate geometry to four Ti4+ and one N2- atom. The N–N bond length is 1.38 Å. In the second N2- site, N2- is bonded in a 5-coordinate geometry to four Ti4+ and one N2- atom. The N–N bond length is 1.38 Å. In the third N2- site, N2- is bonded in a 5-coordinate geometry to four Ti4+ and one N2- atom. In the fourth N2- site, N2- is bonded in a 5-coordinate geometry to four Ti4+ and one N2- atom. The N–N bond length is 1.38 Å. In the fifth N2- site, N2- is bonded in a 5-coordinate geometry to four Ti4+ and one N2- atom. The N–N bond length is 1.38 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KCo(N3O4)2 by Materials Project

K(NO2)4CoN2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is one-dimensional and consists of four diamino cobalt molecules and two K(NO2)4 ribbons oriented in the (1, 0, 0) direction. In each K(NO2)4 ribbon, K1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of K–O bond distances ranging from 2.84–3.11 Å. There are four inequivalent N2+ sites. In the first N2+ site, N2+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both N–O bond lengths are 1.23 Å. In the second N2+ site, N2+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.25 Å) N–O bond length. In the third N2+ site, N2+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.22 Å) and one longer (1.23 Å) N–O bond length. In the fourth N2+ site, N2+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.23 Å) and one longer (1.24 Å) N–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one K1+ and one N2+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to two equivalent K1+ and one N2+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to two equivalent K1+ and one N2+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one N2+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one K1+ and one N2+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent K1+ and one N2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CuH9CSN4Cl3O by Materials Project

CuCN4H3SClH2H2O(HCl)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four hydrochloric acid molecules, two hydrogen molecules, two water molecules, and two CuCN4H3SCl clusters. In each CuCN4H3SCl cluster, Cu2+ is bonded in a distorted trigonal planar geometry to one N2-, one S2-, and one Cl1- atom. The Cu–N bond length is 1.83 Å. The Cu–S bond length is 2.22 Å. The Cu–Cl bond length is 2.44 Å. C4+ is bonded in a linear geometry to two N2- atoms. There is one shorter (1.18 Å) and one longer (1.32 Å) C–N bond length. There are four inequivalent N2- sites. In the first N2- site, N2- is bonded in a 2-coordinate geometry to one Cu2+ and one N2- atom. The N–N bond length is 1.24 Å. In the second N2- site, N2- is bonded in a distorted bent 120 degrees geometry to one N2- and two H1+ atoms. Both N–H bond lengths are 1.04 Å. In the third N2- site, N2- is bonded in a bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.69 Å. In the fourth N2- site, N2- is bonded in a single-bond geometry to one C4+ atom. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one Cl1- atom. The H–Cl bond length is 1.34 Å. S2- is bonded in a 2-coordinate geometry to one Cu2+ and one N2- atom. Cl1- is bonded in a distorted single-bond geometry to one Cu2+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on S(IN)2 by Materials Project

S(NI)2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one S(NI)2 sheet oriented in the (1, 1, -2) direction. there are four inequivalent N2+ sites. In the first N2+ site, N2+ is bonded in a 3-coordinate geometry to one S2- and two I1- atoms. The N–S bond length is 1.57 Å. There are one shorter (2.11 Å) and one longer (2.83 Å) N–I bond lengths. In the second N2+ site, N2+ is bonded in a 1-coordinate geometry to one S2- and two I1- atoms. The N–S bond length is 1.57 Å. There are one shorter (2.11 Å) and one longer (2.76 Å) N–I bond lengths. In the third N2+ site, N2+ is bonded in a 3-coordinate geometry to one S2- and two I1- atoms. The N–S bond length is 1.56 Å. There are one shorter (2.08 Å) and one longer (2.78 Å) N–I bond lengths. In the fourth N2+ site, N2+ is bonded in a distorted trigonal planar geometry to one S2- and two I1- atoms. The N–S bond length is 1.55 Å. There are one shorter (2.08 Å) and one longer (2.75 Å) N–I bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two N2+ atoms. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two N2+ atoms. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded in a linear geometry to two N2+ atoms. In the second I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms. In the third I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms. In the fourth I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on S(IN)2 by Materials Project

S(NI)2 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one S(NI)2 sheet oriented in the (1, 1, 0) direction. there are four inequivalent N2+ sites. In the first N2+ site, N2+ is bonded in a 3-coordinate geometry to one S2- and two I1- atoms. The N–S bond length is 1.57 Å. There are one shorter (2.12 Å) and one longer (2.73 Å) N–I bond lengths. In the second N2+ site, N2+ is bonded in a 3-coordinate geometry to one S2- and two I1- atoms. The N–S bond length is 1.56 Å. There are one shorter (2.12 Å) and one longer (2.67 Å) N–I bond lengths. In the third N2+ site, N2+ is bonded in a distorted trigonal planar geometry to one S2- and two I1- atoms. The N–S bond length is 1.55 Å. There are one shorter (2.08 Å) and one longer (2.74 Å) N–I bond lengths. In the fourth N2+ site, N2+ is bonded in a distorted trigonal planar geometry to one S2- and two I1- atoms. The N–S bond length is 1.55 Å. There are one shorter (2.08 Å) and one longer (2.74 Å) N–I bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two N2+ atoms. In the second S2- site, S2- is bonded in a bent 120 degrees geometry to two N2+ atoms. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded in a linear geometry to two N2+ atoms. In the second I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms. In the third I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms. In the fourth I1- site, I1- is bonded in a distorted linear geometry to two N2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na2N2O3 by Materials Project

Na2N2O3 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a distorted see-saw-like geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.45–2.68 Å. In the second Na1+ site, Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.45–2.95 Å. In the third Na1+ site, Na1+ is bonded in a see-saw-like geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.39–2.46 Å. There are four inequivalent N2+ sites. In the first N2+ site, N2+ is bonded in a bent 120 degrees geometry to two O2- atoms. Both N–O bond lengths are 1.27 Å. In the second N2+ site, N2+ is bonded in a single-bond geometry to one O2- atom. The N–O bond length is 1.27 Å. In the third N2+ site, N2+ is bonded in a single-bond geometry to one O2- atom. The N–O bond length is 1.27 Å. In the fourth N2+ site, N2+ is bonded in a bent 120 degrees geometry to two equivalent O2- atoms. Both N–O bond lengths are 1.27 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one N2+ atom. In the second O2- site, O2- is bonded to three Na1+ and one N2+ atom to form distorted corner-sharing ONa3N tetrahedra. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to four Na1+ and one N2+ atom. In the fourth O2- site, O2- is bonded to three Na1+ and one N2+ atom to form distorted corner-sharing ONa3N tetrahedra. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and one N2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiH10C2(N2O3)2 by Materials Project

NiC2H10(N2O3)2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two NiC2H10(N2O3)2 sheets oriented in the (0, 0, 1) direction. Ni2+ is bonded in an octahedral geometry to two equivalent N2- and four O2- atoms. Both Ni–N bond lengths are 2.08 Å. There are two shorter (2.04 Å) and two longer (2.17 Å) Ni–O bond lengths. C4+ is bonded in a trigonal planar geometry to one N2- and two O2- atoms. The C–N bond length is 1.37 Å. Both C–O bond lengths are 1.28 Å. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a 2-coordinate geometry to one C4+, one N2-, and one H1+ atom. The N–N bond length is 1.41 Å. The N–H bond length is 1.02 Å. In the second N2- site, N2- is bonded in a distorted water-like geometry to one Ni2+, one N2-, and two H1+ atoms. Both N–H bond lengths are 1.03 Å. There are five inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.69 Å) H–O bond length. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Ni2+ and one C4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one C4+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Ni2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on B2H8N by Materials Project

B3H8B(NH4)2 is High Pressure (4-7GPa) Tellurium structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four B(NH4)2 clusters and four B3H8 clusters. In each B(NH4)2 cluster, B3- is bonded in a tetrahedral geometry to two N2- and two H1+ atoms. There is one shorter (1.59 Å) and one longer (1.60 Å) B–N bond length. Both B–H bond lengths are 1.21 Å. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded to one B3- and three H1+ atoms to form corner-sharing NBH3 tetrahedra. All N–H bond lengths are 1.03 Å. In the second N2- site, N2- is bonded to one B3- and three H1+ atoms to form corner-sharing NBH3 tetrahedra. All N–H bond lengths are 1.03 Å. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In each B3H8 cluster, there are three inequivalent B3- sites. In the first B3- site, B3- is bonded in a distorted trigonal non-coplanar geometry to three H1+ atoms. There are a spread of B–H bond distances ranging from 1.21–1.27 Å. In the second B3- site, B3- is bonded in a 4-coordinate geometry to four H1+ atoms. There are a spread of B–H bond distances ranging from 1.21–1.48 Å. In the third B3- site, B3- is bonded in a distorted trigonal non-coplanar geometry to three H1+ atoms. There is two shorter (1.22 Å) and one longer (1.26 Å) B–H bond length. There are seven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in an L-shaped geometry to two B3- atoms. In the second H1+ site, H1+ is bonded in an L-shaped geometry to two B3- atoms. In the third H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one B3- atom.

36 MATERIALS SCIENCE↗
NASA NTRS2016

Physical State and Distribution of Materials at the Surface of Pluto from New Horizons LEISA Imaging Spectrometer

From Earth based observations Pluto is known to be the host of N2, CH4 and CO ices and also a dark red material. Very limited spatial distribution information is available from rotational visible and near-infrared spectral curves obtained from hemispheric measurements. In July 2015 the New Horizons spacecraft reached Pluto and its satellite system and recorded a large set of data. The LEISA spectro-imager of the RALPH instruments are dedicated to the study of the composition and physical state of the materials composing the surface. In this paper we report a study of the distribution and physical state of the ices and non-ice materials on Pluto's illuminated surface and their mode and degree of mixing. Principal Component analysis as well as various specific spectral indicators and correlation plots are used on the first set of 2 high resolution spectro-images from the LEISA instrument covering the whole illuminated face of Pluto at the time of the New Horizons encounter. Qualitative distribution maps have been obtained for the 4 main condensed molecules, N2, CH4, CO, H2O as well as for the visible-dark red material. Based on specific spectral indicators, using either the strength or the position of absorption bands, these 4 molecules are found to indicate the presence of 3 different types of ices: N2-rich:CH4:CO ices, CH4-rich(:CO:N2?) ices and H2O ice. The mixing lines between these ices and with the dark red material are studied using scatter plots between the various spectral indicators. CH4 is mixed at the molecular level with N2, most probably also with CO, thus forming a ternary molecular mixture that follows its phase diagram with low solubility limits. The occurrence of a N2-rich - CH4-rich ices mixing line associated with a progressive decrease of the CO/CH4 ratio tells us that a fractionation sublimation sequence transforms one type of ice to the other forming either a N2-rich - CH4-rich binary mixture at the surface or an upper CH4-rich ice crust that may hide the N2-rich ice below. The strong CH4-rich - H2O mixing line witnesses the subsequent sublimation of the CH4-rich ice lag left behind by the N2:CO sublimation (N spring-summer), or a direct condensation of CH4 ice on the cold H2O ice (S autumn). The weak mixing line between CH4-containing ices and the dark red material and the very sharp spatial transitions between these ices and this non-volatile material are probably due to thermal incompatibility. Finally the occurrence of a H2O ice - red material mixing line advocates for a spatial mixing of the red material covering H2O ice, with possibly a small amount intimately mixed in water ice. From this analysis of the different materials distribution and their relative mixing lines, H2O ice appears to be the substratum on which other ices condense or non-volatile organic material is deposited from the atmosphere. N2-rich ices seem to evolve to CH4-dominated ices, possibly still containing traces of CO and N2, as N2 and CO sublimate away. The spatial distribution of these materials is very complex. The high spatial definition of all these composition maps, as well as those at even higher resolution that will be soon available, will allow us to compare them with Pluto's geologic features observed by LORRI panchromatic and MVIC multispectral imagers to better understand the geophysical processes in action at the surface of this astonishingly active frozen world.

Schmitt, B.↗
DOE OSTI2020

Materials Data on TiH12(NF2)4 by Materials Project

TiF6(N2H6F)2 crystallizes in the orthorhombic Pccn space group. The structure is two-dimensional and consists of four TiF6 clusters and two N2H6F sheets oriented in the (0, 0, 1) direction. In each TiF6 cluster, Ti4+ is bonded in an octahedral geometry to six F1- atoms. There is two shorter (1.88 Å) and four longer (1.90 Å) Ti–F bond length. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Ti4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Ti4+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Ti4+ atom. In each N2H6F sheet, there are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There are a spread of N–H bond distances ranging from 1.05–1.07 Å. In the second N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There is one shorter (1.05 Å) and two longer (1.06 Å) N–H bond length. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.66 Å. In the second H1+ site, H1+ is bonded in a distorted linear geometry to one N2- and one F1- atom. The H–F bond length is 1.55 Å. In the third H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.62 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the sixth H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.62 Å. F1- is bonded in a 4-coordinate geometry to four H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on H5N2F by Materials Project

NH2NH3F crystallizes in the orthorhombic P2_12_12_1 space group. The structure is one-dimensional and consists of eight ammonia molecules and four NH3F ribbons oriented in the (1, 0, 0) direction. In each NH3F ribbon, there are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There is one shorter (1.06 Å) and two longer (1.07 Å) N–H bond length. In the second N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. All N–H bond lengths are 1.06 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.64 Å. In the fourth H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.58 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.64 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.66 Å. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to three H1+ atoms. In the second F1- site, F1- is bonded in a single-bond geometry to one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P3H11N4O9 by Materials Project

NH3NH2P3N2H6O9 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of two ammonia molecules; two ammonia molecules; and one P3N2H6O9 sheet oriented in the (1, 0, 0) direction. In the P3N2H6O9 sheet, there are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.64 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.49–1.63 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There is two shorter (1.50 Å) and two longer (1.62 Å) P–O bond length. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There is one shorter (1.05 Å) and two longer (1.08 Å) N–H bond length. In the second N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There are a spread of N–H bond distances ranging from 1.06–1.08 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted linear geometry to one N2- and one O2- atom. The H–O bond length is 1.58 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one O2- atom. The H–O bond length is 1.59 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fifth H1+ site, H1+ is bonded in a distorted linear geometry to one N2- and one O2- atom. The H–O bond length is 1.59 Å. In the sixth H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one O2- atom. The H–O bond length is 1.64 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one P5+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to one P5+ atom. In the eighth O2- site, O2- is bonded in a distorted single-bond geometry to one P5+ atom. In the ninth O2- site, O2- is bonded in a bent 120 degrees geometry to one P5+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sn3H4(NO5)2 by Materials Project

Sn3H4(NO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four Sn3H4(NO5)2 clusters. there are three inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.20–2.70 Å. In the second Sn4+ site, Sn4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Sn–O bond distances ranging from 2.18–2.31 Å. In the third Sn4+ site, Sn4+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Sn–O bond distances ranging from 2.16–2.76 Å. There are two inequivalent N2+ sites. In the first N2+ site, N2+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.27 Å) and one longer (1.28 Å) N–O bond length. In the second N2+ site, N2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.26–1.28 Å. There are four 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 single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third 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 fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sn4+ and one N2+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to two Sn4+ and one H1+ atom. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to three Sn4+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Sn4+ and one H1+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Sn4+ and one H1+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one N2+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one Sn4+ and one N2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BeH6(NF2)2 by Materials Project

BeH6(NF2)2 is beta Np structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four BeH6(NF2)2 clusters. Be2+ is bonded in a tetrahedral geometry to four F1- atoms. There are a spread of Be–F bond distances ranging from 1.56–1.58 Å. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There is one shorter (1.05 Å) and two longer (1.06 Å) N–H bond length. In the second N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There are a spread of N–H bond distances ranging from 1.03–1.07 Å. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.61 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fourth H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.58 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted bent 120 degrees geometry to one Be2+ and one H1+ atom. In the second F1- site, F1- is bonded in a distorted single-bond geometry to one Be2+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Be2+ atom. In the fourth F1- site, F1- is bonded in a water-like geometry to one Be2+ and one H1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiBH6N by Materials Project

LiBNH6 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is two-dimensional and consists of two LiBNH6 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to one N2- and six H+0.67+ atoms to form distorted LiH6N hexagonal pyramids that share edges with three BH4 tetrahedra. The Li–N bond length is 2.11 Å. There are a spread of Li–H bond distances ranging from 1.97–2.18 Å. In the second Li1+ site, Li1+ is bonded in a 7-coordinate geometry to one N2- and six H+0.67+ atoms. The Li–N bond length is 2.10 Å. There are a spread of Li–H bond distances ranging from 2.01–2.17 Å. There are two inequivalent B3- sites. In the first B3- site, B3- is bonded to four H+0.67+ atoms to form BH4 tetrahedra that share edges with two equivalent LiH6N hexagonal pyramids. There is one shorter (1.22 Å) and three longer (1.23 Å) B–H bond length. In the second B3- site, B3- is bonded to four H+0.67+ atoms to form BH4 tetrahedra that share an edgeedge with one LiH6N hexagonal pyramid. There is one shorter (1.22 Å) and three longer (1.23 Å) B–H bond length. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a distorted water-like geometry to one Li1+ and two H+0.67+ atoms. There is one shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the second N2- site, N2- is bonded in a distorted water-like geometry to one Li1+ and two H+0.67+ atoms. Both N–H bond lengths are 1.03 Å. There are twelve inequivalent H+0.67+ sites. In the first H+0.67+ site, H+0.67+ is bonded in a water-like geometry to one Li1+ and one B3- atom. In the second H+0.67+ site, H+0.67+ is bonded in an L-shaped geometry to one Li1+ and one B3- atom. In the third H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one B3- atom. In the fourth H+0.67+ site, H+0.67+ is bonded in a 3-coordinate geometry to two Li1+ and one B3- atom. In the fifth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N2- atom. In the sixth H+0.67+ site, H+0.67+ is bonded in a distorted T-shaped geometry to two Li1+ and one B3- atom. In the seventh H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N2- atom. In the eighth H+0.67+ site, H+0.67+ is bonded in a 3-coordinate geometry to two Li1+ and one B3- atom. In the ninth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N2- atom. In the tenth H+0.67+ site, H+0.67+ is bonded in a 1-coordinate geometry to two Li1+ and one B3- atom. In the eleventh H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N2- atom. In the twelfth H+0.67+ site, H+0.67+ is bonded in a 3-coordinate geometry to two Li1+ and one B3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GaH8N2OF5 by Materials Project

GaN2H8OF5 crystallizes in the orthorhombic Pbca space group. The structure is two-dimensional and consists of two GaN2H8OF5 sheets oriented in the (0, 0, 1) direction. Ga3+ is bonded in an octahedral geometry to one O2- and five F1- atoms. The Ga–O bond length is 2.01 Å. There are a spread of Ga–F bond distances ranging from 1.90–1.96 Å. There are two inequivalent N2- sites. In the first N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There are a spread of N–H bond distances ranging from 1.05–1.07 Å. In the second N2- site, N2- is bonded in a trigonal non-coplanar geometry to three H1+ atoms. There is two shorter (1.05 Å) and one longer (1.08 Å) N–H bond length. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the second H1+ site, H1+ is bonded in a distorted linear geometry to one O2- and one F1- atom. The H–O bond length is 1.00 Å. The H–F bond length is 1.59 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N2- atom. In the fifth H1+ site, H1+ is bonded in a distorted linear geometry to one N2- and one F1- atom. The H–F bond length is 1.52 Å. In the sixth H1+ site, H1+ is bonded in a linear geometry to one N2- and one F1- atom. The H–F bond length is 1.51 Å. In the seventh H1+ site, H1+ is bonded in a distorted single-bond geometry to one N2- and one F1- atom. The H–F bond length is 1.62 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- and one F1- atom. The H–O bond length is 1.00 Å. The H–F bond length is 1.68 Å. O2- is bonded in a distorted water-like geometry to one Ga3+ and two H1+ atoms. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a 3-coordinate geometry to one Ga3+ and two H1+ atoms. In the second F1- site, F1- is bonded in a bent 150 degrees geometry to one Ga3+ and one H1+ atom. In the third F1- site, F1- is bonded in a 2-coordinate geometry to one Ga3+ and one H1+ atom. In the fourth F1- site, F1- is bonded in a distorted single-bond geometry to one Ga3+ atom. In the fifth F1- site, F1- is bonded in a water-like geometry to one Ga3+ and one H1+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS2009

Defining Nitrogen Kinetics for Air Break in Prebreathe

Actual tissue nitrogen (N2) kinetics are complex; the uptake and elimination is often approximated with a single half-time compartment in statistical descriptions of denitrogenation [prebreathe (PB)] protocols. Air breaks during PB complicate N2 kinetics. A comparison of symmetrical versus asymmetrical N2 kinetics was performed using the time to onset of hypobaric decompression sickness (DCS) as a surrogate for actual venous N2 tension. Published results of 12 tests involving 179 hypobaric exposures in altitude chambers after PB, with and without air breaks, provide the complex protocols from which to model N2 kinetics. DCS survival time for combined control and air breaks were described with an accelerated log logistic model where N2 uptake and elimination before, during, and after the air break was computed with a simple exponential function or a function that changed half-time depending on ambient N2 partial pressure. P1N2-P2 = delta P defined DCS dose for each altitude exposure, where P2 was the test altitude and P1N2 was computed N2 pressure at the beginning of the altitude exposure. The log likelihood (LL) without DCS dose (null model) was -155.6, and improved (best-fit) to -97.2 when dose was defined with a 240 min half-time for both N2 elimination and uptake during the PB. The description of DCS survival time was less precise with asymmetrical N2 kinetics, for example, LL was -98.9 with 240 min half-time elimination and 120 min half-time uptake. The statistical regression described survival time mechanistically linked to symmetrical N2 kinetics during PBs that also included air breaks. The results are data-specific, and additional data may change the conclusion. The regression is useful to compute additional PB time to compensate for an air break in PB within the narrow range of tested conditions.

Conkin, Johnny↗
NASA NTRS2010

Defining Nitrogen Kinetics for Air Break in Prebreath

Actual tissue nitrogen (N2) kinetics are complex; the uptake and elimination is often approximated with a single half-time compartment in statistical descriptions of denitrogenation [prebreathe(PB)] protocols. Air breaks during PB complicate N2 kinetics. A comparison of symmetrical versus asymmetrical N2 kinetics was performed using the time to onset of hypobaric decompression sickness (DCS) as a surrogate for actual venous N2 tension. METHODS: Published results of 12 tests involving 179 hypobaric exposures in altitude chambers after PB, with and without airbreaks, provide the complex protocols from which to model N2 kinetics. DCS survival time for combined control and airbreaks were described with an accelerated log logistic model where N2 uptake and elimination before, during, and after the airbreak was computed with a simple exponential function or a function that changed half-time depending on ambient N2 partial pressure. P1N2-P2 = (Delta)P defined decompression dose for each altitude exposure, where P2 was the test altitude and P1N2 was computed N2 pressure at the beginning of the altitude exposure. RESULTS: The log likelihood (LL) without decompression dose (null model) was -155.6, and improved (best-fit) to -97.2 when dose was defined with a 240 min half-time for both N2 elimination and uptake during the PB. The description of DCS survival time was less precise with asymmetrical N2 kinetics, for example, LL was -98.9 with 240 min half-time elimination and 120 min half-time uptake. CONCLUSION: The statistical regression described survival time mechanistically linked to symmetrical N2 kinetics during PBs that also included airbreaks. The results are data-specific, and additional data may change the conclusion. The regression is useful to compute additional PB time to compensate for an airbreak in PB within the narrow range of tested conditions.

Conkin, Johnny↗