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At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on B10H13 by Materials Project

B10H13 is alpha U-like structured and crystallizes in the orthorhombic Pbca space group. The structure is zero-dimensional and consists of four B10H13 clusters. there are ten inequivalent B sites. In the first B site, B is bonded in a single-bond geometry to one B and one H atom. The B–B bond length is 1.79 Å. The B–H bond length is 1.20 Å. In the second B site, B is bonded in a distorted water-like geometry to two H atoms. There is one shorter (1.19 Å) and one longer (1.33 Å) B–H bond length. In the third B site, B is bonded in a distorted trigonal non-coplanar geometry to three H atoms. There are a spread of B–H bond distances ranging from 1.19–1.35 Å. In the fourth B site, B is bonded in a distorted hexagonal planar geometry to six B atoms. There are a spread of B–B bond distances ranging from 1.73–1.79 Å. In the fifth B site, B is bonded in a water-like geometry to one B and two H atoms. There is one shorter (1.20 Å) and one longer (1.33 Å) B–H bond length. In the sixth B site, B is bonded in a distorted single-bond geometry to one B and one H atom. The B–H bond length is 1.19 Å. In the seventh B site, B is bonded in a distorted single-bond geometry to one B and one H atom. The B–H bond length is 1.20 Å. In the eighth B site, B is bonded in a distorted water-like geometry to two H atoms. There is one shorter (1.20 Å) and one longer (1.33 Å) B–H bond length. In the ninth B site, B is bonded in a water-like geometry to one B and two H atoms. There is one shorter (1.19 Å) and one longer (1.33 Å) B–H bond length. In the tenth B site, B is bonded in a distorted trigonal non-coplanar geometry to three H atoms. There are a spread of B–H bond distances ranging from 1.19–1.35 Å. There are thirteen inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one B atom. In the second H site, H is bonded in a single-bond geometry to one B atom. In the third H site, H is bonded in a single-bond geometry to one B atom. In the fourth H site, H is bonded in a single-bond geometry to one B atom. In the fifth H site, H is bonded in an L-shaped geometry to two B atoms. In the sixth H site, H is bonded in an L-shaped geometry to two B atoms. In the seventh H site, H is bonded in a single-bond geometry to one B atom. In the eighth H site, H is bonded in a single-bond geometry to one B atom. In the ninth H site, H is bonded in a single-bond geometry to one B atom. In the tenth H site, H is bonded in a single-bond geometry to one B atom. In the eleventh H site, H is bonded in an L-shaped geometry to two B atoms. In the twelfth H site, H is bonded in an L-shaped geometry to two B atoms. In the thirteenth H site, H is bonded in a single-bond geometry to one B atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Si3N2 by Materials Project

Si3N2 is alpha Po structured and crystallizes in the cubic Pm-3m space group. The structure is zero-dimensional and consists of one Si3N2 cluster. Si+1.33+ is bonded in a bent 120 degrees geometry to two equivalent N2- atoms. Both Si–N bond lengths are 1.76 Å. N2- is bonded in a trigonal planar geometry to three equivalent Si+1.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ge3N2 by Materials Project

Ge3N2 is alpha Po structured and crystallizes in the cubic Pm-3m space group. The structure is zero-dimensional and consists of one Ge3N2 cluster. Ge2+ is bonded in a bent 120 degrees geometry to two equivalent N3- atoms. Both Ge–N bond lengths are 1.87 Å. N3- is bonded in a trigonal planar geometry to three equivalent Ge2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiS4 by Materials Project

LiS4 is alpha Po-like structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one LiS4 cluster. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a distorted bent 120 degrees geometry to two S+0.25- atoms. There are one shorter (2.33 Å) and one longer (2.34 Å) Li–S bond lengths. In the second Li1+ site, Li1+ is bonded in a 1-coordinate geometry to six S+0.25- atoms. There are a spread of Li–S bond distances ranging from 2.41–3.19 Å. There are eight inequivalent S+0.25- sites. In the first S+0.25- site, S+0.25- is bonded in a 3-coordinate geometry to two Li1+ and one S+0.25- atom. The S–S bond length is 2.07 Å. In the second S+0.25- site, S+0.25- is bonded in a distorted single-bond geometry to one Li1+ and one S+0.25- atom. In the third S+0.25- site, S+0.25- is bonded in a 1-coordinate geometry to one S+0.25- atom. The S–S bond length is 2.09 Å. In the fourth S+0.25- site, S+0.25- is bonded in a 1-coordinate geometry to one Li1+ and two S+0.25- atoms. The S–S bond length is 2.09 Å. In the fifth S+0.25- site, S+0.25- is bonded in a water-like geometry to two S+0.25- atoms. The S–S bond length is 2.08 Å. In the sixth S+0.25- site, S+0.25- is bonded in a 3-coordinate geometry to one Li1+ and two S+0.25- atoms. The S–S bond length is 2.05 Å. In the seventh S+0.25- site, S+0.25- is bonded in a 3-coordinate geometry to one Li1+ and two S+0.25- atoms. The S–S bond length is 2.08 Å. In the eighth S+0.25- site, S+0.25- is bonded in a 3-coordinate geometry to two Li1+ and one S+0.25- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnC5IO5 by Materials Project

IMn(CO)5 is alpha U structured and crystallizes in the orthorhombic Cmcm space group. The structure is zero-dimensional and consists of four IMn(CO)5 clusters. Mn3+ is bonded in a 6-coordinate geometry to five C+1.60+ and one I1- atom. There is one shorter (1.84 Å) and four longer (1.88 Å) Mn–C bond length. The Mn–I bond length is 2.76 Å. There are two inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a distorted single-bond geometry to one Mn3+ and one O2- atom. The C–O bond length is 1.15 Å. In the second C+1.60+ site, C+1.60+ is bonded in a single-bond geometry to one Mn3+ and one O2- atom. The C–O bond length is 1.15 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. I1- is bonded in a single-bond geometry to one Mn3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C3N2 by Materials Project

C3N2 is alpha Po structured and crystallizes in the cubic P-43m space group. The structure is zero-dimensional and consists of one C3N2 cluster. C2+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.43 Å) and one longer (1.44 Å) C–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms. In the second N3- site, N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KGaH9C3F by Materials Project

KGaC3H9F is alpha Po structured and crystallizes in the cubic F-43c space group. The structure is zero-dimensional and consists of eight KGaC3H9F clusters. K1+ is bonded in a distorted T-shaped geometry to three equivalent F1- atoms. All K–F bond lengths are 2.73 Å. Ga3+ is bonded in a tetrahedral geometry to three equivalent C4- and one F1- atom. All Ga–C bond lengths are 1.99 Å. The Ga–F bond length is 2.05 Å. C4- is bonded to one Ga3+ and three H1+ atoms to form distorted CGaH3 tetrahedra that share corners with two equivalent CGaH3 tetrahedra and a cornercorner with one FK3Ga trigonal pyramid. There is one shorter (1.09 Å) and two longer (1.10 Å) C–H bond length. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one C4- atom. F1- is bonded to three equivalent K1+ and one Ga3+ atom to form distorted FK3Ga trigonal pyramids that share corners with three equivalent CGaH3 tetrahedra and edges with three equivalent FK3Ga trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al(CN)3 by Materials Project

Al(CN)3 is alpha Po structured and crystallizes in the trigonal R3m space group. The structure is zero-dimensional and consists of three Al(CN)3 clusters. Al3+ is bonded in a distorted T-shaped geometry to three equivalent N3- atoms. All Al–N bond lengths are 1.97 Å. C2+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a linear geometry to one Al3+ and one C2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on C3N2 by Materials Project

C3N2 is alpha Po structured and crystallizes in the cubic Pm-3m space group. The structure is zero-dimensional and consists of one C3N2 cluster. C2+ is bonded in a bent 120 degrees geometry to two equivalent N3- atoms. Both C–N bond lengths are 1.44 Å. N3- is bonded in a trigonal planar geometry to three equivalent C2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Zr(ClO4)4 by Materials Project

Zr(O4Cl)4 is alpha oxygen structured and crystallizes in the monoclinic Cc space group. The structure is zero-dimensional and consists of four Zr(O4Cl)4 clusters. Zr is bonded to eight O atoms to form distorted ZrO8 hexagonal bipyramids that share edges with four ClO4 tetrahedra. There are a spread of Zr–O bond distances ranging from 2.21–2.26 Å. There are fifteen inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the second O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.53 Å. In the third O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.53 Å. In the fourth O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.54 Å. In the fifth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the sixth O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.54 Å. In the seventh O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the eighth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the ninth O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.53 Å. In the tenth O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.54 Å. In the eleventh O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.54 Å. In the twelfth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the thirteenth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the fourteenth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.42 Å. In the fifteenth O site, O is bonded in a water-like geometry to one Zr and one Cl atom. The O–Cl bond length is 1.53 Å. There are four inequivalent Cl sites. In the first Cl site, Cl is bonded to four O atoms to form ClO4 tetrahedra that share an edgeedge with one ZrO8 hexagonal bipyramid. In the second Cl site, Cl is bonded to four O atoms to form ClO4 tetrahedra that share an edgeedge with one ZrO8 hexagonal bipyramid. In the third Cl site, Cl is bonded to four O atoms to form ClO4 tetrahedra that share an edgeedge with one ZrO8 hexagonal bipyramid. In the fourth Cl site, Cl is bonded to four O atoms to form ClO4 tetrahedra that share an edgeedge with one ZrO8 hexagonal bipyramid.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ZnC2N6(ClO)2 by Materials Project

ZnC2N6(OCl)2 is alpha structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two ZnC2N6(OCl)2 clusters. Zn2+ is bonded in a distorted square co-planar geometry to two equivalent N+0.67-, two equivalent O2-, and two equivalent Cl1- atoms. Both Zn–N bond lengths are 2.88 Å. Both Zn–O bond lengths are 2.43 Å. Both Zn–Cl bond lengths are 2.16 Å. C4+ is bonded in a linear geometry to one N+0.67- and one O2- atom. The C–N bond length is 1.22 Å. The C–O bond length is 1.20 Å. There are three inequivalent N+0.67- sites. In the first N+0.67- site, N+0.67- is bonded in a single-bond geometry to one N+0.67- atom. The N–N bond length is 1.11 Å. In the second N+0.67- site, N+0.67- is bonded in a distorted bent 150 degrees geometry to one Zn2+ and one N+0.67- atom. In the third N+0.67- site, N+0.67- is bonded in a single-bond geometry to one C4+ atom. O2- is bonded in a 2-coordinate geometry to one Zn2+ and one C4+ atom. Cl1- is bonded in a single-bond geometry to one Zn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Time-Resolved Radioluminescence of the Polynuclear Copper(I) Phosphor Cu4I6²–. Different Temporal responses to Photo, X-Ray, β-Ray and α-Particle Excitation

Described for the first time are the time-resolved radioluminescence (TRRL) properties of the highly luminescent copper(I) cluster Cu4I62– using X-ray, b-ray and a-particle excitation. The copper(I) phosphors are two crystalline salts of this anion, [Na2(18-crown-6)2(H2O)3][Cu4I6] (I) and [Li(benzo-15-crown-5)2(H2O)]2[Cu4I6] (II), that had been shown to display strong photoluminescence (PL) when excited with ultraviolet light. The integrated radioluminescence (RL) spectra observed when pulsed X-rays were used as the excitation source are virtually the same as the PL spectra under comparable conditions. These temporal RL spectra are invariant at all observation times indicating that the observed scintillation occurs from a common excited state (or set of excited states). When the TRRL is collected from excitation with a pulsed X-ray source, b-ray decay from 90Sr or a-decay from 244Cm, the longer components (>2 μs) of the TRRL displayed (in each case) lifetimes comparable to those of the strictly exponential PL decays recorded under pulsed laser UV excitation. However, at shorter observation times (< 500 ns), the RL decay deviated from the exponential model, indicating a markedly different temporal luminescence behavior when these materials were excited with pulsed high energy radiation. Furthermore, this effect was the most pronounced for the a-particle excitation. These results suggest that the absorption of a very high energy X-ray photon, b-ray or a-particle at a site within the crystalline solid leads to a high local density of electronic excited states and that coupling between these states provides an alternative channel for excited state decay. Given that the patterns observed

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
NASA NTRS1994

X-ray emission associated with radio galaxies in the Perseus cluster

In this paper, we report on new x-ray observations of the Perseus cluster made using four separate pointings of the Roentgen Satellite (ROSAT) Positron Sensitive Proportional Counter (PSPC). We searched for x-ray emission associated with 16 radio galaxies and detected six above 3 sigma. We made use of the PSPC spectra to determine if the x-ray emission associated with radio galaxies in Perseus is thermal or nonthermal in origin (i.e., hot gas or an active galactic nuclei (AGN)). For the head-tail radio galaxy IC 310, we find that the data are best fit by a power law model with an unusually large spectral index alpha = 2.7. This is consistent with its unresolved spatial structure. On the other hand, a second resolved x-ray source associated with another radio galaxy 2.3 Mpc from the Perseus center (V Zw 331) is best fit by a thermal model. For three sources with insufficient flux for a full spectral analysis, we calculated hardness ratios. On this basis, the x-ray emission associated with the well known head-tail source NGC 1265 is consistent with thermal radiation. The x-ray spectra of UGC 2608 and UGC 2654 probably arise from hot gas, although very steep power-law spectra (alpha greater than 3.2) are also possible. The spectrum of NGC 1275 is quite complex due to the presence of an AGN and the galaxy's location at the center of a cluster cooling flow.

Rhee, George↗
DOE OSTI2020

Materials Data on S by Materials Project

S is alpha-like structured and crystallizes in the orthorhombic P2_12_12_1 space group. The structure is zero-dimensional and consists of four S clusters. there are eighteen inequivalent S sites. In the first S site, S is bonded in a water-like geometry to two S atoms. Both S–S bond lengths are 2.07 Å. In the second S site, S is bonded in a water-like geometry to two S atoms. Both S–S bond lengths are 2.07 Å. In the third S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.06 Å. In the fourth S site, S is bonded in a water-like geometry to two S atoms. Both S–S bond lengths are 2.07 Å. In the fifth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.07 Å. In the sixth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.07 Å. In the seventh S site, S is bonded in a water-like geometry to two S atoms. Both S–S bond lengths are 2.07 Å. In the eighth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.06 Å. In the ninth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.07 Å. In the tenth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.07 Å. In the eleventh S site, S is bonded in a water-like geometry to two S atoms. There are one shorter (2.06 Å) and one longer (2.07 Å) S–S bond lengths. In the twelfth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.06 Å. In the thirteenth S site, S is bonded in a water-like geometry to two S atoms. In the fourteenth S site, S is bonded in a water-like geometry to two S atoms. The S–S bond length is 2.07 Å. In the fifteenth S site, S is bonded in a water-like geometry to two S atoms. In the sixteenth S site, S is bonded in a water-like geometry to two S atoms. In the seventeenth S site, S is bonded in a water-like geometry to two S atoms. In the eighteenth S site, S is bonded in a water-like geometry to two S atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on HIO3 by Materials Project

HIO3 is alpha Niobium phosphide-derived structured and crystallizes in the orthorhombic Pbca space group. The structure is zero-dimensional and consists of four HIO3 clusters. H1+ is bonded in a single-bond geometry to two O2- atoms. There is one shorter (1.01 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 single-bond geometry to one I5+ atom. The O–I bond length is 1.84 Å. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one H1+ and one I5+ atom. The O–I bond length is 1.91 Å. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one H1+ and one I5+ atom. The O–I bond length is 1.82 Å. I5+ is bonded in a 6-coordinate geometry to three O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on BTe3(OF5)3 by Materials Project

BTe3(OF5)3 is alpha-like structured and crystallizes in the hexagonal P6_3/m space group. The structure is zero-dimensional and consists of two BTe3(OF5)3 clusters. B3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All B–O bond lengths are 1.38 Å. Te6+ is bonded in an octahedral geometry to one O2- and five F1- atoms. The Te–O bond length is 1.92 Å. All Te–F bond lengths are 1.87 Å. O2- is bonded in a distorted bent 120 degrees geometry to one B3+ and one Te6+ atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Te6+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ag(BCl)6 by Materials Project

Ag(BCl)6 is alpha-like structured and crystallizes in the cubic Pa-3 space group. The structure is zero-dimensional and consists of eight Ag(BCl)6 clusters. Ag is bonded in a 6-coordinate geometry to six Cl atoms. There are three shorter (2.87 Å) and three longer (2.88 Å) Ag–Cl bond lengths. There are two inequivalent B sites. In the first B site, B is bonded in a single-bond geometry to one Cl atom. The B–Cl bond length is 1.79 Å. In the second B site, B is bonded in a single-bond geometry to one Cl atom. The B–Cl bond length is 1.80 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a distorted single-bond geometry to one Ag and one B atom. In the second Cl site, Cl is bonded in a distorted water-like geometry to one Ag and one B atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on W2NCl9 by Materials Project

W2NCl9 is alpha U-like structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two W2NCl9 clusters. there are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded in an octahedral geometry to one N3- and five Cl1- atoms. The W–N bond length is 1.98 Å. All W–Cl bond lengths are 2.31 Å. In the second W6+ site, W6+ is bonded in a 6-coordinate geometry to one N3- and five Cl1- atoms. The W–N bond length is 1.76 Å. There are a spread of W–Cl bond distances ranging from 2.29–2.93 Å. N3- is bonded in a linear geometry to two W6+ atoms. There are nine inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the fifth Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the sixth Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the seventh Cl1- site, Cl1- is bonded in a distorted water-like geometry to two equivalent W6+ atoms. In the eighth Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom. In the ninth Cl1- site, Cl1- is bonded in a single-bond geometry to one W6+ atom.

36 MATERIALS SCIENCE↗