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At least 739 records · Page 41
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Mn2InC10BrO10 by Materials Project

(Mn(CO)5)2InBr crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one InBr cluster and four Mn(CO)5 clusters. In the InBr cluster, In1+ is bonded in an L-shaped geometry to two equivalent Br1- atoms. There are one shorter (2.78 Å) and one longer (2.79 Å) In–Br bond lengths. Br1- is bonded in a distorted water-like geometry to two equivalent In1+ atoms. In two of the Mn(CO)5 clusters, Mn2+ is bonded in a square pyramidal geometry to five C+1.60+ atoms. There are a spread of Mn–C bond distances ranging from 1.81–1.87 Å. There are five inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. There are five 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. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In two of the Mn(CO)5 clusters, Mn2+ is bonded in a square pyramidal geometry to five C+1.60+ atoms. There are a spread of Mn–C bond distances ranging from 1.82–1.86 Å. There are five inequivalent C+1.60+ sites. In the first C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+1.60+ site, C+1.60+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. There are five 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. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+1.60+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn2PH9(C4O3)3 by Materials Project

Mn(CO)4Mn(CO)5P(CH3)3 is Potassium thiocyanate-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four trimethylphosphine molecules, four Mn(CO)4 clusters, and four Mn(CO)5 clusters. In each Mn(CO)4 cluster, Mn2+ is bonded in a rectangular see-saw-like geometry to four C atoms. There are a spread of Mn–C bond distances ranging from 1.83–1.85 Å. There are four inequivalent C sites. In the first C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.17 Å. In the second C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.17 Å. In the third C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.17 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C atom. In each Mn(CO)5 cluster, Mn2+ is bonded in a square pyramidal geometry to five C atoms. There is one shorter (1.80 Å) and four longer (1.85 Å) Mn–C bond length. There are five inequivalent C sites. In the first C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.17 Å. In the second C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C site, C is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.17 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Zeolite-Stabilized Di- and Tetranuclear Molybdenum Sulfide Clusters Form Stable Catalytic Hydrogenation Sites

Supercages of faujasite (FAU)-type zeolites serve as a robust scaffold for stabilizing dinuclear (Mo 2 S 4 ) and tetranuclear (Mo 4 S 4 ) molybdenum sulfide clusters. The FAU-encaged Mo 4 S 4 clusters have a distorted cubane structure similar to the FeMo-cofactor in nitrogenase. Both clusters possess one unpaired electron per Mo atom. Additionally, they show identical catalytic activity per sulfide cluster. Their catalytic activity is stable (> 150 h) for ethene hydrogenation, while layered MoS 2 structures deactivate significantly under the same reaction conditions.

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

Materials Data on SN by Materials Project

NS crystallizes in the triclinic P1 space group. The structure is one-dimensional and consists of four NS clusters and four NS ribbons oriented in the (1, 0, 0) direction. In two of the NS clusters, N1+ is bonded in a single-bond geometry to one S1- atom. The N–S bond length is 1.48 Å. S1- is bonded in a single-bond geometry to one N1+ atom. In two of the NS clusters, there are three inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a distorted single-bond geometry to one S1- atom. The N–S bond length is 1.61 Å. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S1- atoms. There is one shorter (1.60 Å) and one longer (1.61 Å) N–S bond length. In the third N1+ site, N1+ is bonded in a bent 150 degrees geometry to two S1- atoms. There is one shorter (1.57 Å) and one longer (1.60 Å) N–S bond length. There are three inequivalent S1- sites. In the first S1- site, S1- is bonded in a water-like geometry to two N1+ atoms. In the second S1- site, S1- is bonded in a bent 120 degrees geometry to two N1+ atoms. In the third S1- site, S1- is bonded in a distorted single-bond geometry to one N1+ atom. In one of the NS ribbons, there are four inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S1- atoms. There is one shorter (1.58 Å) and one longer (1.69 Å) N–S bond length. In the second N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S1- atoms. There is one shorter (1.59 Å) and one longer (1.69 Å) N–S bond length. In the third N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S1- atoms. There is one shorter (1.59 Å) and one longer (1.72 Å) N–S bond length. In the fourth N1+ site, N1+ is bonded in a bent 120 degrees geometry to two S1- atoms. There is one shorter (1.59 Å) and one longer (1.72 Å) N–S bond length. There are four inequivalent S1- sites. In the first S1- site, S1- is bonded in a distorted trigonal non-coplanar geometry to three N1+ atoms. In the second S1- site, S1- is bonded in a distorted trigonal non-coplanar geometry to three N1+ atoms. In the third S1- site, S1- is bonded in a distorted single-bond geometry to one N1+ atom. In the fourth S1- site, S1- is bonded in a distorted single-bond geometry to one N1+ atom. In three of the NS ribbons, there are two inequivalent N1+ sites. In the first N1+ site, N1+ is bonded in a bent 150 degrees geometry to two S1- atoms. There is one shorter (1.59 Å) and one longer (1.62 Å) N–S bond length. In the second N1+ site, N1+ is bonded in a bent 150 degrees geometry to two S1- atoms. There is one shorter (1.59 Å) and one longer (1.62 Å) N–S bond length. There are two inequivalent S1- sites. In the first S1- site, S1- is bonded in a bent 120 degrees geometry to two N1+ atoms. In the second S1- site, S1- is bonded in a bent 120 degrees geometry to two N1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Structural investigation of the temperature-stable relaxor dielectric Ba 0.8 Ca 0.2 TiO 3 -Bi(Mg 0.5 Ti 0.5 )O 3

Aberration corrected scanning transmission electron microscopy (STEM) and electron diffraction have been used to disclose local structure and nano-chemistry in a Ca modified BaTiO 3 -Bi(Mg 0.5 Ti 0.5 )O 3 relax or dielectric ceramic which exhibits high and near-invariant relative permittivity over a wide temperature range. High resolution, synchrotron X-ray diffraction indicated a globally cubic structure ($Pm$$\overline{3}$$m$), but direct atomic-scale imaging by STEM revealed local tetragonal distortions. Nanopolar clusters were identified from B-site atomic displacement vectors measured relative to oxygen ion positions along < 100 > and < 110 > zone axes of integrated differential phase contrast (iDPC) STEM images, highlighting cluster sizes of 2–5 nm. Chemical analysis by STEM-energy dispersive X-ray spectroscopy and full pattern refinements of X-ray powder diffraction data each implied high levels of Bi vacancies within the matrix. The possibility that these A-site vacancies modulate the nanopolar structure and promote flattening of the permittivity-temperature response in this class of dielectric is discussed.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sb(MoS2)6 by Materials Project

(MoS2)6Sb crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one antimony molecule and four MoS2 clusters. In two of the MoS2 clusters, Mo+4.50+ is bonded in a 2-coordinate geometry to two S2- atoms. There are one shorter (2.32 Å) and one longer (2.33 Å) Mo–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to one Mo+4.50+ and one S2- atom. The S–S bond length is 2.08 Å. In the second S2- site, S2- is bonded in a 2-coordinate geometry to one Mo+4.50+ and one S2- atom. In two of the MoS2 clusters, there are two inequivalent Mo+4.50+ sites. In the first Mo+4.50+ site, Mo+4.50+ is bonded in a 1-coordinate geometry to two S2- atoms. There are one shorter (2.32 Å) and one longer (2.33 Å) Mo–S bond lengths. In the second Mo+4.50+ site, Mo+4.50+ is bonded in a 1-coordinate geometry to two S2- atoms. There are one shorter (2.32 Å) and one longer (2.33 Å) Mo–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 2-coordinate geometry to one Mo+4.50+ and one S2- atom. The S–S bond length is 2.09 Å. In the second S2- site, S2- is bonded in a 1-coordinate geometry to one Mo+4.50+ and one S2- atom. The S–S bond length is 2.09 Å. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one Mo+4.50+ and two S2- atoms. The S–S bond length is 3.75 Å. In the fourth S2- site, S2- is bonded in a 1-coordinate geometry to one Mo+4.50+ and two S2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(MoS2)6 by Materials Project

Hg(MoS2)6 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one mercury molecule and four MoS2 clusters. In two of the MoS2 clusters, Mo+3.67+ is bonded in a 1-coordinate geometry to two S2- atoms. Both Mo–S bond lengths are 2.32 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to one Mo+3.67+ and one S2- atom. The S–S bond length is 2.08 Å. In the second S2- site, S2- is bonded in a 1-coordinate geometry to one Mo+3.67+ and one S2- atom. In two of the MoS2 clusters, there are two inequivalent Mo+3.67+ sites. In the first Mo+3.67+ site, Mo+3.67+ is bonded in a 1-coordinate geometry to two S2- atoms. Both Mo–S bond lengths are 2.32 Å. In the second Mo+3.67+ site, Mo+3.67+ is bonded in a 1-coordinate geometry to two S2- atoms. There are one shorter (2.31 Å) and one longer (2.32 Å) Mo–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 2-coordinate geometry to one Mo+3.67+ and one S2- atom. The S–S bond length is 2.08 Å. In the second S2- site, S2- is bonded in a 1-coordinate geometry to one Mo+3.67+ and one S2- atom. The S–S bond length is 2.08 Å. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one Mo+3.67+ and two S2- atoms. The S–S bond length is 4.07 Å. In the fourth S2- site, S2- is bonded in a distorted single-bond geometry to one Mo+3.67+ and two S2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Fe4Sn(CO)16 by Materials Project

(Fe(CO)4)4Sn crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four 7440-31-5 molecules and sixteen Fe(CO)4 clusters. In four of the Fe(CO)4 clusters, Fe3+ is bonded in a see-saw-like geometry to four C1+ atoms. There is one shorter (1.77 Å) and three longer (1.81 Å) Fe–C bond length. There are four inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C1+ site, C1+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C1+ site, C1+ is bonded in a linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C1+ site, C1+ is bonded in a distorted linear geometry to one Fe3+ 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 C1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In four of the Fe(CO)4 clusters, Fe3+ is bonded in a distorted see-saw-like geometry to four C1+ atoms. There are a spread of Fe–C bond distances ranging from 1.77–1.81 Å. There are four inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a distorted single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C1+ site, C1+ is bonded in a distorted single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C1+ site, C1+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C1+ site, C1+ is bonded in a linear geometry to one Fe3+ 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 C1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In eight of the Fe(CO)4 clusters, Fe3+ is bonded in a distorted see-saw-like geometry to four C1+ atoms. There are a spread of Fe–C bond distances ranging from 1.78–1.81 Å. There are four inequivalent C1+ sites. In the first C1+ site, C1+ is bonded in a linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C1+ site, C1+ is bonded in a distorted single-bond geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C1+ site, C1+ is bonded in a distorted linear geometry to one Fe3+ and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C1+ site, C1+ is bonded in a distorted single-bond geometry to one Fe3+ 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 C1+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C1+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Os2Pt(CO)10 by Materials Project

(Os(CO)4)2Pt(CO)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four Os(CO)4 clusters and two Pt(CO)2 clusters. In two of the Os(CO)4 clusters, Os1- is bonded in a distorted see-saw-like geometry to four C+2.40+ atoms. There are a spread of Os–C bond distances ranging from 1.91–1.96 Å. There are four inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os1- 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+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In two of the Os(CO)4 clusters, Os1- is bonded in a distorted rectangular see-saw-like geometry to four C+2.40+ atoms. There are a spread of Os–C bond distances ranging from 1.91–1.96 Å. There are four inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os1- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os1- 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+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In each Pt(CO)2 cluster, Pt2- is bonded in a distorted water-like geometry to two C+2.40+ atoms. Both Pt–C bond lengths are 1.91 Å. There are two inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Pt2- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Pt2- and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ru3N12(Cl4O3)2 by Materials Project

Ru(Ru(NO)2)2(N2Cl)2(N2OCl3)2 crystallizes in the orthorhombic Immm space group. The structure is one-dimensional and consists of two ruthenium molecules; four N2Cl clusters; four Ru(NO)2 clusters; and two N2OCl3 ribbons oriented in the (1, 0, 0) direction. In each N2Cl cluster, N+0.33+ is bonded in a single-bond geometry to one Cl1- atom. The N–Cl bond length is 1.57 Å. Cl1- is bonded in a distorted bent 120 degrees geometry to two equivalent N+0.33+ atoms. In each Ru(NO)2 cluster, Ru+5.33+ is bonded in a distorted tetrahedral geometry to two equivalent N+0.33+ and two equivalent O2- atoms. Both Ru–N bond lengths are 1.72 Å. Both Ru–O bond lengths are 1.82 Å. N+0.33+ is bonded in a distorted single-bond geometry to one Ru+5.33+ atom. O2- is bonded in a single-bond geometry to one Ru+5.33+ atom. In each N2OCl3 ribbon, N+0.33+ is bonded in an L-shaped geometry to two equivalent Cl1- atoms. Both N–Cl bond lengths are 1.80 Å. O2- is bonded in a distorted single-bond geometry to one O2- and four Cl1- atoms. The O–O bond length is 1.22 Å. There are two shorter (2.93 Å) and two longer (2.94 Å) O–Cl bond lengths. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two equivalent N+0.33+ and one O2- atom. In the second Cl1- site, Cl1- is bonded in a distorted bent 150 degrees geometry to two equivalent O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mn2Fe(CO)14 by Materials Project

(Mn(CO)5)2Fe(CO)4 crystallizes in the monoclinic C2/m space group. The structure is zero-dimensional and consists of four Fe(CO)4 clusters and eight Mn(CO)5 clusters. In two of the Fe(CO)4 clusters, Fe2+ is bonded in a square co-planar geometry to four C+1.57+ atoms. There is two shorter (1.82 Å) and two longer (1.83 Å) Fe–C bond length. There are two inequivalent C+1.57+ sites. In the first C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Fe2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Fe2+ and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In two of the Fe(CO)4 clusters, Fe2+ is bonded in a square co-planar geometry to four equivalent C+1.57+ atoms. There is two shorter (1.82 Å) and two longer (1.83 Å) Fe–C bond length. C+1.57+ is bonded in a linear geometry to one Fe2+ and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. The O–C bond length is 1.16 Å. In four of the Mn(CO)5 clusters, Mn2+ is bonded in a square pyramidal geometry to five C+1.57+ atoms. There are a spread of Mn–C bond distances ranging from 1.81–1.87 Å. There are three inequivalent C+1.57+ sites. In the first C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ 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+1.57+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In four of the Mn(CO)5 clusters, Mn2+ is bonded in a square pyramidal geometry to five C+1.57+ atoms. There are a spread of Mn–C bond distances ranging from 1.82–1.87 Å. There are three inequivalent C+1.57+ sites. In the first C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the second C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ and one O2- atom. The C–O bond length is 1.16 Å. In the third C+1.57+ site, C+1.57+ is bonded in a linear geometry to one Mn2+ 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+1.57+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+1.57+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Cobalt Carbonyl Clusters Enable Independent Control of Two Proton Transfer Rates in the Mechanism for Hydrogen Evolution

Abstract Metal carbonyl clusters (MCC's) are atomically defined nanomaterials which can be characterized using the precise tools of molecular (electro)chemistry. HER mechanisms involve two proton transfer (PT) steps in the catalytic cycle. For HER catalyzed by [Co 11 C 2 (CO) 23 ] 3− ( 1 3− ), cyclic voltammetry measurements were used to determine the rate for PT1 as k PT1 =3×10 8 M −1 s −1 , whereas the rate for PT2 is k PT2 =3.7×10 3 M −1 s −1 . The fast, diffusion‐limited rate for PT1 is consistent with a previous report describing [Co 13 C 2 (CO) 24 ] 4− ( 2 4− ), with PT=2.9×10 9 M −1 s −1 . In both cases rate enhancement in PT1 is promoted by the many Co−Co bonds on the surface of the MCC that serve as PT sites: a statistical enhancement of rate akin to the effects of proton relays. In contrast, k PT2 varies and is five orders of magnitude slower for 1 2− compared with 2 4− . Thus, MCC's and nanomaterials offer an opportunity to enhance the rate for PT1 while maintaining thermochemical or kinetic control of PT2.

Pattanayak, Santanu↗
DOE OSTI2026

Electric-field-assisted-sintering of rare-earth oxide dispersion strengthened Fe-Cr-Mo alloys

Oxide dispersion-strengthened (ODS) alloys are widely recognized for their exceptional high-temperature strength, creep resistance, and radiation tolerance, making them indispensable for advanced nuclear reactors, aerospace, and energy systems. Achieving a fine and stable dispersion of oxide nanoparticles is critical, as these particles act as strong barriers to dislocation motion and effective sinks for irradiation-induced defects, ensuring structural integrity under extreme conditions. Here, in this study, Fe–Cr–Mo-based ODS alloys were fabricated via mechanical alloying and consolidated using electric-field-assisted sintering (EFAS) with additions of Y 2 O 3 , La 2 O 3 , and CeO 2 . EFAS processing produced ultrafine-grained microstructures (average grain size <1 μm) with uniformly distributed oxide clusters (2–4 nm). Atom probe tomography revealed that La 2 O 3 -containing alloys exhibited the highest nanoparticle number density, resulting in superior tensile strength compared to yttria- and ceria-bearing counterparts. The combined effect of grain refinement and rare-earth oxide dispersion significantly enhanced mechanical performance, demonstrating the potential of EFAS for developing high-strength ferritic alloys for demanding environments such as nuclear systems.

36 - MATERIALS SCIENCE↗
DOE OSTI2022

Combined Rotating Disk Slurry Electrodeposition–Spontaneous Galvanic Displacement for Pt-M (M = Co, Ni, and Cu) Catalyst Synthesis for the Oxygen Reduction Reaction in Alkaline Media

Here, platinum-modified first-row transition-metal catalyst (M = Ni, Co, and Cu) nanoparticles on a carbon black Vulcan XC-72R (CBV) support were synthesized using rotating disk slurry electrodeposition (RoDSE) followed by spontaneous galvanic displacement (SGD) reactions. These RoDSE–SGD catalysts were evaluated for the oxygen reduction reaction (ORR) in 0.1 M KOH using rotating disk electrode techniques. The Ni and Co RoDSEs were done by using an electrochemical applied potential of -0.75 V versus the RHE and for Cu, -0.80 V versus the RHE using a CBV slurry solution containing 0.1 M KClO 4 . These metal nanoparticles on CBV (M/CBV) catalysts were modified with a Pt precursor via a spontaneous galvanic displacement (SGD) reaction, producing a Pt-M/CBV material to catalyze the ORR in an alkaline medium. High-resolution scanning transmission electron microscopy (HR-STEM) analysis indicates that the PtM/CBV samples include M clusters and Pt single atoms. The ORR characterization measurements were done under a controlled temperature (25.0 °C) and with a mass loading of 100 μg/cm 2 on a glassy carbon (GC) rotating disk electrode at 1600 rpm. The PtCo/CBV showed the highest ORR mass activity of 0.741 A/mgPt at 0.90 V versus the reversible hydrogen electrode (RHE) compared with commercial Pt/CBV. The M/CBV RoDSE catalysts were also tested for the oxygen evolution reaction (OER), and Ni/CBV provided the lowest overpotential of 450 mV at 10 mA/cm 2 disk in 0.1 M KOH.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2020

Effect of Collective Dynamics and Anharmonicity on Entropy in Heterogenous Catalysis: Building the Case for Advanced Molecular Simulations

In this paper, we present a perspective on the computational determination of entropy and its effects and consequences on heterogeneous catalysis. Special attention is paid to the role of anharmonicity and the deviations from the standard harmonic oscillator approximations which can fail to provide a reliable assessment of entropy. To address these challenges, advanced methodologies are needed that can explicitly account for these thermodynamic drivers through the appropriate statistical sampling of reactive free energy surfaces. We discuss where anharmonicity should be expected, where it has been observed from a theoretical perspective, and the methods currently employed to address it. We concentrate on three types of systems where we have observed major, nonnegligible anharmonic effects: (1) supported nanoparticles, where the migration of metal atoms, complexes, and entire clusters exhibit anharmonic behavior in their dynamic motion; (2) porous solids where confinement effects distort potential energy surfaces and hinder molecular motions resulting in large entropic terms; and (3) solid/liquid interfaces, where interactions between solvent molecules and adsorbed species can result in large solvent organization free energy and unique reactivity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Potential energy profile for the Cl + (H 2 O) 3 → HCl + (H 2 O) 2 OH reaction. A CCSD(T) study

Four different reaction pathways are initially located for the reaction of Cl atom plus water trimer Cl + (H 2 O) 3 → HCl + (H 2 O) 2 OH using a standard DFT method. As found for the analogous fluorine reaction, the geometrical and energetic results for the four chlorine pathways are closely related. However, the energetics for the Cl reaction are very different from those for fluorine. Here in this paper, we investigate the lowest-energy chlorine pathway using the “gold standard” CCSD(T) method in conjunction with correlation-consistent basis sets up to cc-pVQZ. Structurally, the stationary points for the water trimer reaction Cl + (H 2 O) 3 may be compared to those for the water monomer reaction Cl + H 2 O and water dimer reaction Cl + (H 2 O) 2 . Based on the CCSD(T) energies, the title reaction is endothermic by 19.3 kcal mol -1 , with a classical barrier height of 16.7 kcal mol -1 between the reactants and the exit complex. There is no barrier for the reverse reaction. The Cl … (H 2 O) 3 entrance complex lies 5.3 kcal mol -1 below the separated reactants. The HCl … (H 2 O) 2 OH exit complex is bound by 8.6 kcal mol -1 relative to the separated products. The Cl + (H 2 O) 3 reaction is somewhat similar to the analogous Cl + (H 2 O) 2 reaction, but qualitatively different from the Cl + H 2 O reaction. It is reasonable to expect that the reactions between the chlorine atom and larger water clusters may be similar to the Cl + (H 2 O) 3 reaction. The potential energy profile for the Cl + (H 2 O) 3 reaction is radically different from that for the valence isoelectronic F + (H 2 O) 3 system, which may be related to the different bond energies between HCl and HF.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗