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At least 685 records · Page 38
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DOE OSTI2020

Materials Data on YB3(H5N)6 by Materials Project

Y(NH3)6(BH4)3 crystallizes in the cubic P2_13 space group. The structure is zero-dimensional and consists of twelve BH4 clusters and four Y(NH3)6 clusters. In each BH4 cluster, B3- is bonded in a tetrahedral geometry to four H+0.80+ atoms. All B–H bond lengths are 1.23 Å. There are two inequivalent H+0.80+ sites. In the first H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one B3- atom. In the second H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one B3- atom. In each Y(NH3)6 cluster, Y3+ is bonded in an octahedral geometry to six N3- atoms. All Y–N bond lengths are 2.44 Å. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and three H+0.80+ atoms. There is two shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. In the second N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to one Y3+ and three H+0.80+ atoms. All N–H bond lengths are 1.03 Å. There are six inequivalent H+0.80+ sites. In the first H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom. In the second H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom. In the third H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom. In the fourth H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom. In the fifth H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom. In the sixth H+0.80+ site, H+0.80+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Be(N3O7)2 by Materials Project

Be(NO2)3Be(NO2)4(NO2)5(O2)2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two hydrogen peroxide molecules, five nitrous acid molecules, one Be(NO2)3 cluster, and one Be(NO2)4 cluster. In the Be(NO2)3 cluster, Be2+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of Be–O bond distances ranging from 1.54–1.61 Å. There are three inequivalent N+4.33+ sites. In the first N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.22 Å) and one longer (1.34 Å) N–O bond length. In the second N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.20 Å) and one longer (1.37 Å) N–O bond length. In the third N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.21 Å) and one longer (1.31 Å) N–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the Be(NO2)4 cluster, Be2+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Be–O bond distances ranging from 1.57–1.71 Å. There are four inequivalent N+4.33+ sites. In the first N+4.33+ site, N+4.33+ is bonded in a water-like geometry to two O2- atoms. Both N–O bond lengths are 1.29 Å. In the second N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.23 Å) and one longer (1.28 Å) N–O bond length. In the third N+4.33+ site, N+4.33+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.21 Å) and one longer (1.35 Å) N–O bond length. In the fourth N+4.33+ site, N+4.33+ is bonded in a 3-coordinate geometry to three O2- atoms. There is two shorter (1.18 Å) and one longer (2.04 Å) N–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N+4.33+ atom. In the second O2- site, O2- is bonded in an L-shaped geometry to one Be2+ and one N+4.33+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two N+4.33+ atoms. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the sixth O2- site, O2- is bonded in an L-shaped geometry to one Be2+ and one N+4.33+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one N+4.33+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Be2+ and one N+4.33+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on UCu(Mo2O9)6 by Materials Project

U(Mo2O7)6CuO12 is Modderite-like structured and crystallizes in the trigonal R-3 space group. The structure is zero-dimensional and consists of three CuO12 clusters and three U(Mo2O7)6 clusters. In each CuO12 cluster, Cu is bonded in an octahedral geometry to six equivalent O atoms. All Cu–O bond lengths are 2.19 Å. There are two inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.22 Å. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Cu and one O atom. In each U(Mo2O7)6 cluster, U is bonded in a cuboctahedral geometry to twelve O atoms. There are six shorter (2.43 Å) and six longer (2.46 Å) U–O bond lengths. There are two inequivalent Mo sites. In the first Mo site, Mo is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mo–O bond distances ranging from 1.73–2.38 Å. In the second Mo site, Mo is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mo–O bond distances ranging from 1.73–2.34 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted rectangular see-saw-like geometry to one U and three Mo atoms. In the second O site, O is bonded in a single-bond geometry to one Mo atom. In the third O site, O is bonded in a single-bond geometry to one Mo atom. In the fourth O site, O is bonded in a single-bond geometry to one Mo atom. In the fifth O site, O is bonded in a single-bond geometry to one Mo atom. In the sixth O site, O is bonded in a distorted rectangular see-saw-like geometry to one U and three Mo atoms. In the seventh O site, O is bonded in a water-like geometry to two Mo atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ThMg(N3O13)2 by Materials Project

MgO8Th(NO3)6 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two MgO8 clusters and two Th(NO3)6 clusters. In each MgO8 cluster, Mg is bonded in a distorted octahedral geometry to six O atoms. There are two shorter (2.08 Å) and four longer (2.16 Å) Mg–O bond lengths. There are four inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two O atoms. Both O–O bond lengths are 1.31 Å. In the second O site, O is bonded in a single-bond geometry to one Mg atom. In the third O site, O is bonded in an L-shaped geometry to one Mg and one O atom. In the fourth O site, O is bonded in an L-shaped geometry to one Mg and one O atom. In each Th(NO3)6 cluster, Th is bonded in a cuboctahedral geometry to twelve O atoms. There are a spread of Th–O bond distances ranging from 2.56–2.64 Å. There are three inequivalent N sites. In the first N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.22–1.30 Å. In the second N site, N is bonded in a trigonal planar geometry to three O atoms. There is one shorter (1.25 Å) and two longer (1.27 Å) N–O bond length. In the third N site, N is bonded in a trigonal planar geometry to three O atoms. There are a spread of N–O bond distances ranging from 1.23–1.29 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the second O site, O is bonded in a single-bond geometry to one N atom. In the third O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the fourth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the fifth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the sixth O site, O is bonded in a single-bond geometry to one N atom. In the seventh O site, O is bonded in a distorted single-bond geometry to one Th and one N atom. In the eighth O site, O is bonded in a single-bond geometry to one N atom. In the ninth O site, O is bonded in a distorted single-bond geometry to one Th and one N atom.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Efficient time-dependent orbital-free density functional theory: Semilocal adiabatic response

Orbital-free density functional theory and its time-dependent extension are efficient ab initio methods for calculating the electronic structure and dynamics of large systems. Through the calculation of the optical spectra of selected clusters, we reach three important conclusions: (1) The quality of the spectra is strongly affected by the quality of the corresponding ground-state electron density; (2) the adiabatic part of the electronic response to external perturbations can be safely evaluated at the semilocal level; and (3) the nonadiabatic, current-dependent part of the time-dependent Pauli potential is key to recover correct spectral envelopes.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiH18(IN)6 by Materials Project

Ni(NH3)6(I)6 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight I clusters and four Ni(NH3)6 clusters. In four of the I clusters, there are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a linear geometry to two equivalent I1- atoms. Both I–I bond lengths are 2.97 Å. In the second I1- site, I1- is bonded in a distorted single-bond geometry to one I1- atom. In four of the I clusters, there are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a linear geometry to two equivalent I1- atoms. Both I–I bond lengths are 2.96 Å. In the second I1- site, I1- is bonded in a distorted single-bond geometry to one I1- atom. In each Ni(NH3)6 cluster, Ni2+ is bonded in an octahedral geometry to six N+2.33- atoms. There are four shorter (2.13 Å) and two longer (2.14 Å) Ni–N bond lengths. There are three inequivalent N+2.33- sites. In the first N+2.33- site, N+2.33- is bonded in a distorted trigonal non-coplanar geometry to one Ni2+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. In the second N+2.33- site, N+2.33- is bonded in a distorted trigonal non-coplanar geometry to one Ni2+ and three H1+ atoms. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the third N+2.33- site, N+2.33- is bonded in a distorted trigonal non-coplanar geometry to one Ni2+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. There are nine inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one N+2.33- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Os5(CO)19 by Materials Project

Os(CO)3(Os(CO)4)4 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Os(CO)3 clusters and eight Os(CO)4 clusters. In each Os(CO)3 cluster, Os+1.20- is bonded in a T-shaped geometry to three C+2.32+ atoms. There is one shorter (1.89 Å) and two longer (1.94 Å) Os–C bond length. There are three inequivalent C+2.32+ sites. In the first C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.17 Å. In the third C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In two of the Os(CO)4 clusters, Os+1.20- is bonded in a rectangular see-saw-like geometry to four C+2.32+ atoms. There are a spread of Os–C bond distances ranging from 1.90–1.96 Å. There are four inequivalent C+2.32+ sites. In the first C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.15 Å. In the second C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.32+ site, C+2.32+ is bonded in a linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In two of the Os(CO)4 clusters, Os+1.20- is bonded in a rectangular see-saw-like geometry to four C+2.32+ atoms. There are a spread of Os–C bond distances ranging from 1.91–1.97 Å. There are four inequivalent C+2.32+ sites. In the first C+2.32+ site, C+2.32+ is bonded in a linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.15 Å. In the third C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.32+ site, C+2.32+ is bonded in a linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In two of the Os(CO)4 clusters, Os+1.20- is bonded in a rectangular see-saw-like geometry to four C+2.32+ atoms. There are a spread of Os–C bond distances ranging from 1.91–1.96 Å. There are four inequivalent C+2.32+ sites. In the first C+2.32+ site, C+2.32+ is bonded in a linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In two of the Os(CO)4 clusters, Os+1.20- is bonded in a rectangular see-saw-like geometry to four C+2.32+ atoms. There are a spread of Os–C bond distances ranging from 1.91–1.96 Å. There are four inequivalent C+2.32+ sites. In the first C+2.32+ site, C+2.32+ is bonded in a linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.32+ site, C+2.32+ is bonded in a distorted linear geometry to one Os+1.20- and one O2- atom. The C–O bond length is 1.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.32+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Tuning the Coordination Environment of Rh Single Atoms on Highly Dispersed Reducible Oxides for Enhanced Reverse Water-Gas Shift Performance

Controlling the dynamic mobility of catalyst surface active sites and their interactions with the surrounding environment is critical in generating active surfaces that directly influence the catalytic activity and selectivity. Here, we report a strategy for tailoring the dispersion and electronic environment of single atom Rh catalysts by decorating the alumina support with highly dispersed (HD) cerium and molybdenum oxides. The resulting catalysts exhibit markedly different behavior in the Reverse Water Gas Shift (RWGS) reaction. In particular, Rh/MoOx(HD)/Al2O3 maintains atomically dispersed Rh even at elevated temperatures (up to 400 °C), achieving CO selectivity of up to 100% and resists sintering via the formation of a newly developed structure featuring Rh single atoms embedded in MoOx clusters. In situ spectroscopy and microscopy analyses confirm the stabilization of Rh and the dynamic evolution of Rh–Mo coordination under reaction conditions. Our findings highlight the power of support modification in steering active site structure and activity, offering a pathway toward enhanced and tunable single atom catalysts for CO2 valorization.

CO selectivity↗
DOE OSTI2023

Electronic Structure and Anion Photoelectron Spectroscopy of Uranium–Gold Clusters UAu n – , n = 3–7

A collaborative effort between experiment and theory towards elucidating the electronic and molecular structures of uranium-gold clusters is presented. Anion photoelectron spectra of UAu n – (n=3-7) were taken at third (355 nm) and fourth (266 nm) harmonics of a Nd:YAG laser, as well as excimer (ArF 193nm) photon energies, where the experimental adiabatic electron affinities (AEA) and vertical detachment energies (VDE) values were measured. Complementary first principles calculations were subsequently carried out to corroborate experimentally determined electron detachment energies and to determine the geometry and electronic structure for each cluster. Except for the ring-like neutral isomer of UAu 6 where one unpaired electron is spread over the Au atoms, all other neutral and anionic UAu n clusters (n = 3 - 7) were calculated to possess open-shell electrons with the unpaired electrons localized on the central U atom. The smaller clusters closely resemble the analogous UF n species, but significant deviations are seen starting with UAu 5 where a competition between U-Au and Au-Au bonding begins to become apparent. The UAu 6 system appears to mark a transition where Au-Au interactions begin to dominate, where both a ring-like and two heavily distorted octahedral structures around the central U atom are to be nearly isoenergetic. With UAu 7 , only ring-like structures are calculated. Altogether, the calculated electron detachment energies are in good agreement with the experimental values

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on AlH18Ru(NF)6 by Materials Project

Ru(NH3)6AlF6 is Halite, Rock Salt structured and crystallizes in the cubic Pa-3 space group. The structure is zero-dimensional and consists of four AlF6 clusters and four Ru(NH3)6 clusters. In each AlF6 cluster, Al3+ is bonded in an octahedral geometry to six equivalent F1- atoms. All Al–F bond lengths are 1.84 Å. F1- is bonded in a single-bond geometry to one Al3+ atom. In each Ru(NH3)6 cluster, Ru3+ is bonded in an octahedral geometry to six equivalent N3- atoms. All Ru–N bond lengths are 2.12 Å. N3- is bonded in a distorted trigonal non-coplanar geometry to one Ru3+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li3AsH36(SeN3)4 by Materials Project

(Li(NH3)4)3AsSe4 is Silicon tetrafluoride-derived structured and crystallizes in the cubic I-43m space group. The structure is zero-dimensional and consists of two AsSe4 clusters and six Li(NH3)4 clusters. In each AsSe4 cluster, As5+ is bonded in a tetrahedral geometry to four equivalent Se2- atoms. All As–Se bond lengths are 2.35 Å. Se2- is bonded in a single-bond geometry to one As5+ atom. In each Li(NH3)4 cluster, Li1+ is bonded in a tetrahedral geometry to four equivalent N3- atoms. All Li–N bond lengths are 2.17 Å. N3- is bonded in a distorted trigonal non-coplanar geometry to one Li1+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiB(H3N)4 by Materials Project

Li(NH2)4BH4 crystallizes in the orthorhombic Pca2_1 space group. The structure is zero-dimensional and consists of four BH4 clusters and four Li(NH2)4 clusters. In each BH4 cluster, B3+ is bonded in a tetrahedral geometry to four H+0.67+ atoms. There is two shorter (1.23 Å) and two longer (1.24 Å) B–H bond length. There are four inequivalent H+0.67+ sites. In the first H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one B3+ atom. In the second H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to 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 single-bond geometry to one B3+ atom. In each Li(NH2)4 cluster, Li1+ is bonded in a distorted tetrahedral geometry to four N3- atoms. There are a spread of Li–N bond distances ranging from 2.06–2.14 Å. There are four inequivalent N3- sites. In the first N3- site, N3- 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 N3- site, N3- 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. In the third N3- site, N3- 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. In the fourth N3- site, N3- 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 eight inequivalent H+0.67+ sites. In the first H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the second H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the third H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the fourth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the fifth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the sixth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the seventh H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom. In the eighth H+0.67+ site, H+0.67+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiAlH8C16(O2F9)4 by Materials Project

Li(H2O)4Al(CO)4(CF3)12 crystallizes in the tetragonal I-4 space group. The structure is zero-dimensional and consists of twenty-four fluoroform molecules, two Al(CO)4 clusters, and two Li(H2O)4 clusters. In each Al(CO)4 cluster, Al3+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Al–O bond lengths are 1.75 Å. C+2.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.35 Å. O2- is bonded in a bent 150 degrees geometry to one Al3+ and one C+2.50+ atom. In each Li(H2O)4 cluster, Li1+ is bonded in a tetrahedral geometry to four equivalent O2- atoms. All Li–O bond lengths are 1.94 Å. There are two 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 0.97 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. O2- is bonded in a trigonal planar geometry to one Li1+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CdAs2C4SN4(OF6)2 by Materials Project

CdC4AsN4S(OF3)2AsF6 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of four AsF6 clusters and four CdC4AsN4S(OF3)2 clusters. In each AsF6 cluster, As5+ is bonded in an octahedral geometry to six F1- atoms. There is three shorter (1.77 Å) and three longer (1.78 Å) As–F bond length. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In each CdC4AsN4S(OF3)2 cluster, Cd2+ is bonded in a 7-coordinate geometry to four N+2.50-, one O2-, and two equivalent F1- atoms. There are a spread of Cd–N bond distances ranging from 2.34–2.46 Å. The Cd–O bond length is 2.34 Å. Both Cd–F bond lengths are 2.62 Å. There are three inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a single-bond geometry to one N+2.50- atom. The C–N bond length is 1.16 Å. In the second C4+ site, C4+ is bonded in a single-bond geometry to one N+2.50- atom. The C–N bond length is 1.16 Å. In the third C4+ site, C4+ is bonded in a single-bond geometry to one N+2.50- atom. The C–N bond length is 1.16 Å. As5+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.76–1.81 Å. There are three inequivalent N+2.50- sites. In the first N+2.50- site, N+2.50- is bonded in a 1-coordinate geometry to one Cd2+ and one C4+ atom. In the second N+2.50- site, N+2.50- is bonded in a 1-coordinate geometry to one Cd2+ and one C4+ atom. In the third N+2.50- site, N+2.50- is bonded in a 1-coordinate geometry to one Cd2+ and one C4+ atom. S2- is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.44 Å) and one longer (1.46 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Cd2+ and one S2- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one S2- atom. There are four inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one Cd2+ and one As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on TeH9SN2O5F3 by Materials Project

(NH4)2HTeSO5F3 is Iron carbide-derived structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of four ammonium molecules and two HTeSO5F3 clusters. In one of the HTeSO5F3 clusters, H1+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.01 Å) and one longer (1.66 Å) H–O bond length. Te4+ is bonded in a 4-coordinate geometry to one O2- and three F1- atoms. The Te–O bond length is 1.93 Å. There are a spread of Te–F bond distances ranging from 1.93–2.04 Å. S2- is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.52 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one Te4+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one S2- atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one H1+ and one S2- atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S2- atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one S2- atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom. In one of the HTeSO5F3 clusters, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.01 Å. Te4+ is bonded in a 5-coordinate geometry to two O2- and three F1- atoms. There are one shorter (1.93 Å) and one longer (2.37 Å) Te–O bond lengths. There are a spread of Te–F bond distances ranging from 1.98–2.03 Å. S2- is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.47–1.54 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one S2- atom. In the second O2- site, O2- is bonded in a single-bond geometry to one S2- atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one H1+ and one Te4+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S2- atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Te4+ and one S2- atom. There are three inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one Te4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Ab initio study of the structure and properties of amorphous silicon hydride from accelerated molecular dynamics simulations

This paper presents a large-scale ab initio simulation study of amorphous silicon hydride (a-Si 1-x H x ) with an emphasis on the structure and properties of the material across a range of hydrogen concentration by combining accelerated molecular dynamics (MD) simulations with first-principles density-functional calculations. The accelerated MD scheme relied on classical metadynamics, which enabled the development of 2500+ high-quality structural models of a-Si 1-x H x , with system sizes ranging from 150 to 6000 atoms and hydrogen concentrations vary from 6 to 20 at. %. The resulting amorphous networks were found to be completely free from any coordination defects and that they all exhibited a pristine band-gap in their electronic spectrum. The microstructural properties of hydrogen distributions were examined with an emphasis on the presence of isolated and clustered environments of hydrogen atoms. The results were compared with experimental data obtained from X-ray diffraction, infrared spectroscopy and nuclear magnetic resonance studies.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Atom Efficiency of Pd Sites for Methane Combustion: Single Atom Catalysts Versus Nanocatalysts

Methane combustion is an important reaction for energy production and methane removal from the atmosphere. This reaction highly relies on the use of noble metal Pd-based catalysts, which therefore drives the pursuit of catalysts with high atomic dispersion and activity. In this work, Pd/ceria catalysts dominated with Pd single atoms or nanosized Pd clusters (∼1 nm) are prepared and characterized by combining high-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), in situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS), and Raman and X-ray absorption spectroscopy (XAS) techniques. By comparing the turnover frequencies (TOF; per every Pd atom) of Pd/ceria single atom catalysts and nanocatalysts, it is found that the atom efficiency of Pd is increased by 10 ∼30 times from single atom catalysts to nanocatalysts. For Pd single atom catalysts, although their activity can be tuned by changing the local structures, the intrinsic activity and number of active sites need to be further improved by engineering the surfaces of supports. For nanosized Pd species, despite the high TOF, the Pd atoms in the bulk structure are not directly participating in the catalytic reaction. Furthermore, this work highlights the importance of increasing the intrinsic activity of individual noble atoms, as well as the homogeneity of their local structures. For Pd/ceria systems reported in this work, our results indicate that from the application point of view, at the current stage, it is not practical to replace Pd nanocatalysts with single atom catalysts for methane combustion.

Pd↗
DOE OSTI2023

Ab initio study of the structure and properties of amorphous silicon hydride from accelerated molecular dynamics simulations

This paper presents a large-scale ab initio simulation study of amorphous silicon hydride (a-Si 1-x H x ) with an emphasis on the structure and properties of the material across a range of hydrogen concentration by combining accelerated molecular dynamics (MD) simulations with first-principles density-functional calculations. The accelerated MD scheme relied on classical metadynamics, which enabled the development of 2600+ high-quality structural models of a-Si 1-x H x , with system sizes ranging from 150 to 6,000 atoms and hydrogen concentrations vary from 6 to 20 at. %. The resulting amorphous networks were found to be completely free from any coordination defects and that they all exhibited a pristine band-gap in their electronic spectrum. The microstructural properties of hydrogen distributions were examined with great emphasis on the presence of isolated and clustered environments of hydrogen atoms. The results were compared with a suite of experimental data obtained from x-ray diffraction, infrared spectroscopy, spectroscopic ellipsometry and nuclear magnetic resonance studies.

36 MATERIALS SCIENCE↗