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DOE OSTI2020

Materials Data on Ti2H2CSe4Cl16O5 by Materials Project

Ti2OCl6CO2(HSeOCl2)2(SeCl)2(Cl2)2 crystallizes in the monoclinic P2/c space group. The structure is zero-dimensional and consists of two carbon dioxide molecules, four chlorine molecules, four chloroselenurane molecules, two HSeOCl2 clusters, and two Ti2OCl6 clusters. In each HSeOCl2 cluster, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. Se3+ is bonded in a distorted L-shaped geometry to one O2- and one Cl1- atom. The Se–O bond length is 1.81 Å. The Se–Cl bond length is 2.39 Å. O2- is bonded in a distorted water-like geometry to one H1+ and one Se3+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted linear geometry to two Cl1- atoms. There are one shorter (2.08 Å) and one longer (2.92 Å) Cl–Cl bond lengths. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Se3+ and one Cl1- atom. In each Ti2OCl6 cluster, Ti4+ is bonded to one O2- and three Cl1- atoms to form corner-sharing TiCl3O tetrahedra. The Ti–O bond length is 1.79 Å. There are two shorter (2.19 Å) and one longer (2.21 Å) Ti–Cl bond lengths. O2- is bonded in a linear geometry to two equivalent Ti4+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ti4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on V6SbH35C12Cl8O19 by Materials Project

V6C11H33O19CH2Cl2SbCl6 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two dichloromethane molecules, two SbCl6 clusters, and two V6C11H33O19 clusters. In each SbCl6 cluster, Sb is bonded in an octahedral geometry to six Cl atoms. There are a spread of Sb–Cl bond distances ranging from 2.41–2.43 Å. There are six inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In the second Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In the third Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In the fourth Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In the fifth Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In the sixth Cl site, Cl is bonded in a single-bond geometry to one Sb atom. In each V6C11H33O19 cluster, there are six inequivalent V sites. In the first V site, V is bonded in a 6-coordinate geometry to six O atoms. There are a spread of V–O bond distances ranging from 1.61–2.38 Å. In the second V site, V is bonded in a 6-coordinate geometry to six O atoms. There are a spread of V–O bond distances ranging from 1.62–2.39 Å. In the third V site, V is bonded in a 6-coordinate geometry to six O atoms. There are a spread of V–O bond distances ranging from 1.62–2.34 Å. In the fourth V site, V is bonded to six O atoms to form distorted VO6 octahedra that share corners with four CH3O tetrahedra. There are a spread of V–O bond distances ranging from 1.61–2.22 Å. In the fifth V site, V is bonded in a 6-coordinate geometry to six O atoms. There are a spread of V–O bond distances ranging from 1.62–2.32 Å. In the sixth V site, V is bonded in a 6-coordinate geometry to six O atoms. There are a spread of V–O bond distances ranging from 1.61–2.25 Å. There are eleven inequivalent C sites. In the first C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the second C site, C is bonded to three H and one O atom to form CH3O tetrahedra that share a cornercorner with one VO6 octahedra. The corner-sharing octahedral tilt angles are 56°. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the third C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the fourth C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.45 Å. In the fifth C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the sixth C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.45 Å. In the seventh C site, C is bonded to three H and one O atom to form CH3O tetrahedra that share a cornercorner with one VO6 octahedra. The corner-sharing octahedral tilt angles are 57°. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the eighth C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the ninth C site, C is bonded to three H and one O atom to form CH3O tetrahedra that share a cornercorner with one VO6 octahedra. The corner-sharing octahedral tilt angles are 52°. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the tenth C site, C is bonded to three H and one O atom to form CH3O tetrahedra that share a cornercorner with one VO6 octahedra. The corner-sharing octahedral tilt angles are 58°. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. In the eleventh C site, C is bonded in a tetrahedral geometry to three H and one O atom. All C–H bond lengths are 1.10 Å. The C–O bond length is 1.44 Å. There are thirty-three inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to one C atom. In the second H site, H is bonded in a single-bond geometry to one C atom. In the third H site, H is bonded in a single-bond geometry to one C atom. In the fourth H site, H is bonded in a single-bond geometry to one C atom. In the fifth H site, H is bonded in a single-bond geometry to one C atom. In the sixth H site, H is bonded in a single-bond geometry to one C atom. In the seventh H site, H is bonded in a single-bond geometry to one C atom. In the eighth H site, H is bonded in a single-bond geometry to one C atom. In the ninth H site, H is bonded in a single-bond geometry to one C atom. In the tenth H site, H is bonded in a single-bond geometry to one C atom. In the eleventh H site, H is bonded in a single-bond geometry to one C atom. In the twelfth H site, H is bonded in a single-bond geometry to one C atom. In the thirteenth H site, H is bonded in a single-bond geometry to one C atom. In the fourteenth H site, H is bonded in a single-bond geometry to one C atom. In the fifteenth H site, H is bonded in a single-bond geometry to one C atom. In the sixteenth H site, H is bonded in a single-bond geometry to one C atom. In the seventeenth H site, H is bonded in a single-bond geometry to one C atom. In the eighteenth H site, H is bonded in a single-bond geometry to one C atom. In the nineteenth H site, H is bonded in a single-bond geometry to one C atom. In the twentieth H site, H is bonded in a single-bond geometry to one C atom. In the twenty-first H site, H is bonded in a single-bond geometry to one C atom. In the twenty-second H site, H is bonded in a single-bond geometry to one C atom. In the twenty-third H site, H is bonded in a single-bond geometry to one C atom. In the twenty-fourth H site, H is bonded in a single-bond geometry to one C atom. In the twenty-fifth H site, H is bonded in a single-bond geometry to one C atom. In the twenty-sixth H site, H is bonded in a single-bond geometry to one C atom. In the twenty-seventh H site, H is bonded in a single-bond geometry to one C atom. In the twenty-eighth H site, H is bonded in a single-bond geometry to one C atom. In the twenty-ninth H site, H is bonded in a single-bond geometry to one C atom. In the thirtieth H site, H is bonded in a single-bond geometry to one C atom. In the thirty-first H site, H is bonded in a single-bond geometry to one C atom. In the thirty-second H site, H is bonded in a single-bond geometry to one C atom. In the thirty-third H site, H is bonded in a single-bond geometry to one C atom. There are nineteen inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one V atom. In the second O site, O is bonded in a single-bond geometry to one V atom. In the third O site, O is bonded in a single-bond geometry to one V atom. In the fourth O site, O is bonded in a single-bond geometry to one V atom. In the fifth O site, O is bonded in a bent 120 degrees geometry to two V atoms. In the sixth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the seventh O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the eighth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the ninth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the tenth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the eleventh O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the twelfth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the thirteenth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the fourteenth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the fifteenth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the sixteenth O site, O is bonded in a trigonal planar geometry to two V and one C atom. In the seventeenth O site, O is bonded in an octahedral geometry to six V atoms. In the eighteenth O site, O is bonded in a single-bond geometry to one V atom. In the nineteenth O site, O is bonded in a single-bond geometry to one V atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al(BiCl)4 by Materials Project

(Bi)4AlCl4 crystallizes in the hexagonal P6_3 space group. The structure is zero-dimensional and consists of twelve AlCl4 clusters and six Bi clusters. In each AlCl4 cluster, Al is bonded in a tetrahedral geometry to four Cl atoms. There are three shorter (2.16 Å) and one longer (2.17 Å) Al–Cl bond lengths. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one Al atom. In the second Cl site, Cl is bonded in a single-bond geometry to one Al atom. In each Bi cluster, there are eight inequivalent Bi sites. In the first Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are a spread of Bi–Bi bond distances ranging from 3.09–3.18 Å. In the second Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are one shorter (3.10 Å) and two longer (3.19 Å) Bi–Bi bond lengths. In the third Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are a spread of Bi–Bi bond distances ranging from 3.09–3.18 Å. In the fourth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. There are one shorter (3.08 Å) and one longer (3.10 Å) Bi–Bi bond lengths. In the fifth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. The Bi–Bi bond length is 3.08 Å. In the sixth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. Both Bi–Bi bond lengths are 3.19 Å. In the seventh Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. The Bi–Bi bond length is 3.08 Å. In the eighth Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Promoting the cleavage of C-O bonds at the interface between a metal oxide cluster and a Co(0001) support

As a first step toward the rational design of Co-based catalysts with a higher activity and selectivity, we determine how one can activate a C-O bond at the interface between a metal oxide cluster and a Co(0001) support. The hypothesis here is that the metal ions in metal oxide clusters on a Co(0001) support enhance the adsorption of CO and weaken the C-O bond strength, which can then facilitate the dissociation of the CO reactant. To test this hypothesis, we developed three computational models of Ti4O8/Co(0001), Zr4O8/Co(0001), and Mn8O8/Co(0001). We quantify the CO adsorption behavior at the interface sites between an oxide cluster and the Co(0001) support as well as the corresponding IR spectra. We correlate the computed CO stretch frequencies with their CO adsorption energies, as well as the CO stretch frequency with the C-O bond length, and related these findings to the changes in the chemical bonding in the bound CO. The interface is the most favorable site for CO adsorption. Adsorption results in an increase of the C-O bond length and a decrease in its vibrational frequency. From a chemical bonding analysis, the bond order in CO at this site drops from 3 (in the gas phase) to 1. This decrease in bond order is a necessary precursor stage for CO dissociation. The experimental measurements of the corresponding FTIR spectra support this point. The favorability of CO adsorption at the interface sites is due to an electron transfer from the metal ion in the metal oxide cluster to the O atom in CO. We establish a linear relationship between C-O bond length and CO frequency and this relationship is found to be independent of the support, type of metal oxide cluster, or the adsorption site.

Fischer-Tropsch Synthesis, Heterogeneous Catalysis↗
DOE OSTI2020

Materials Data on AsS3(NF3)2 by Materials Project

N2S3AsF6 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two AsF6 clusters and two N2S3 clusters. In each AsF6 cluster, As2+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.77–1.80 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a distorted single-bond geometry to one As2+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In each N2S3 cluster, there are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.58 Å) and one longer (1.60 Å) N–S bond length. In the second N5+ site, N5+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.58 Å) and one longer (1.60 Å) N–S bond length. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a single-bond geometry to one N5+ atom. In the second S2- site, S2- is bonded in a distorted water-like geometry to two N5+ atoms. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsSe3(NF3)2 by Materials Project

N2Se3AsF6 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four AsF6 clusters and four N2Se3 clusters. In each AsF6 cluster, As2+ 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 six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the third F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In each N2Se3 cluster, there are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a bent 120 degrees geometry to two Se2- atoms. There is one shorter (1.75 Å) and one longer (1.77 Å) N–Se bond length. In the second N5+ site, N5+ is bonded in a bent 120 degrees geometry to two Se2- atoms. There is one shorter (1.75 Å) and one longer (1.77 Å) N–Se bond length. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted single-bond geometry to one N5+ atom. In the second Se2- site, Se2- is bonded in a distorted single-bond geometry to one N5+ atom. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to two N5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AsS3(NF3)2 by Materials Project

N2S3AsF6 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four AsF6 clusters and four N2S3 clusters. In each AsF6 cluster, As2+ is bonded in an octahedral geometry to six F1- atoms. There are a spread of As–F bond distances ranging from 1.76–1.83 Å. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the third F1- site, F1- is bonded in a distorted single-bond geometry to one As2+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As2+ atom. In each N2S3 cluster, there are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.58 Å) and one longer (1.60 Å) N–S bond length. In the second N5+ site, N5+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.58 Å) and one longer (1.60 Å) N–S bond length. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted single-bond geometry to one N5+ atom. In the second S2- site, S2- is bonded in a water-like geometry to two N5+ atoms. In the third S2- site, S2- is bonded in a distorted single-bond geometry to one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GaSe3N2Cl5 by Materials Project

GaCl4N2Se3Cl crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four GaCl4 clusters and four N2Se3Cl clusters. In each GaCl4 cluster, Ga3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are a spread of Ga–Cl bond distances ranging from 2.19–2.23 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Ga3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In each N2Se3Cl cluster, there are two inequivalent N4+ sites. In the first N4+ site, N4+ is bonded in a bent 120 degrees geometry to two Se2- atoms. There is one shorter (1.73 Å) and one longer (1.76 Å) N–Se bond length. In the second N4+ site, N4+ is bonded in a bent 120 degrees geometry to two Se2- atoms. There is one shorter (1.75 Å) and one longer (1.80 Å) N–Se bond length. There are three inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted single-bond geometry to one N4+ atom. In the second Se2- site, Se2- is bonded in a distorted water-like geometry to one N4+ and one Cl1- atom. The Se–Cl bond length is 2.28 Å. In the third Se2- site, Se2- is bonded in a water-like geometry to two N4+ atoms. Cl1- is bonded in a single-bond geometry to one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al3Bi5Br12 by Materials Project

(Bi)5(AlBr4)3 is Iron carbide-derived structured and crystallizes in the trigonal R-3c space group. The structure is zero-dimensional and consists of eighteen AlBr4 clusters and six Bi clusters. In each AlBr4 cluster, Al is bonded in a tetrahedral geometry to four Br atoms. There are two shorter (2.32 Å) and two longer (2.34 Å) Al–Br bond lengths. There are two inequivalent Br sites. In the first Br site, Br is bonded in a single-bond geometry to one Al atom. In the second Br site, Br is bonded in a single-bond geometry to one Al atom. In each Bi cluster, there are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 6-coordinate geometry to three equivalent Bi atoms. All Bi–Bi bond lengths are 3.09 Å. In the second Bi site, Bi is bonded in a 4-coordinate geometry to four Bi atoms. Both Bi–Bi bond lengths are 3.24 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al3Bi5Cl12 by Materials Project

(Bi)5(AlCl4)3 is Iron carbide-derived structured and crystallizes in the trigonal R-3c space group. The structure is zero-dimensional and consists of eighteen AlCl4 clusters and six Bi clusters. In each AlCl4 cluster, Al is bonded in a tetrahedral geometry to four Cl atoms. There are two shorter (2.15 Å) and two longer (2.18 Å) Al–Cl bond lengths. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a single-bond geometry to one Al atom. In the second Cl site, Cl is bonded in a single-bond geometry to one Al atom. In each Bi cluster, there are two inequivalent Bi sites. In the first Bi site, Bi is bonded in a 2-coordinate geometry to two equivalent Bi atoms. Both Bi–Bi bond lengths are 3.06 Å. In the second Bi site, Bi is bonded in a 6-coordinate geometry to three equivalent Bi atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SmBiO4 by Materials Project

SmO2BiO2 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two BiO2 clusters and two SmO2 clusters. In each BiO2 cluster, Bi5+ is bonded in a distorted linear geometry to two O2- atoms. There is one shorter (1.40 Å) and one longer (1.45 Å) Bi–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Bi5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one Bi5+ atom. In each SmO2 cluster, Sm3+ is bonded in a distorted bent 120 degrees geometry to two O2- atoms. There is one shorter (1.37 Å) and one longer (1.95 Å) Sm–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Sm3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Sm3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ErGa6 by Materials Project

ErGa2(Ga)4 crystallizes in the tetragonal P4/mmm space group. The structure is zero-dimensional and consists of two ErGa2 clusters and two Ga clusters. In each ErGa2 cluster, Er is bonded in a linear geometry to two equivalent Ga atoms. Both Er–Ga bond lengths are 2.82 Å. Ga is bonded in a single-bond geometry to one Er atom. In each Ga cluster, Ga is bonded in an L-shaped geometry to two equivalent Ga atoms. Both Ga–Ga bond lengths are 2.58 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Fe2S3O23 by Materials Project

FeSO7Fe(SO6)2(O2)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four molecular oxygen molecules, two Fe(SO6)2 clusters, and two FeSO7 clusters. In each Fe(SO6)2 cluster, Fe is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Fe–O bond distances ranging from 1.86–2.41 Å. There are two inequivalent S sites. In the first S site, S is bonded in a tetrahedral geometry to four O atoms. There is three shorter (1.47 Å) and one longer (1.54 Å) S–O bond length. In the second S site, S is bonded in a tetrahedral geometry to four O atoms. There are a spread of S–O bond distances ranging from 1.46–1.54 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one S atom. In the second O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. The O–O bond length is 1.30 Å. In the third O site, O is bonded in a single-bond geometry to one S atom. In the fourth O site, O is bonded in a single-bond geometry to one O atom. The O–O bond length is 1.24 Å. In the fifth O site, O is bonded in a single-bond geometry to one S atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Fe and one S atom. In the seventh O site, O is bonded in a water-like geometry to one Fe and one O atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one Fe and one O atom. In the ninth O site, O is bonded in a single-bond geometry to one S atom. In the tenth O site, O is bonded in a single-bond geometry to one S atom. In the eleventh O site, O is bonded in a single-bond geometry to one S atom. In the twelfth O site, O is bonded in a bent 150 degrees geometry to one Fe and one S atom. In each FeSO7 cluster, Fe is bonded in a see-saw-like geometry to four O atoms. There are a spread of Fe–O bond distances ranging from 1.66–1.84 Å. S is bonded in a tetrahedral geometry to four O atoms. There are a spread of S–O bond distances ranging from 1.46–1.56 Å. There are seven inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Fe and one S atom. In the second O site, O is bonded in a single-bond geometry to one Fe atom. In the third O site, O is bonded in a single-bond geometry to one Fe atom. In the fourth O site, O is bonded in a single-bond geometry to one Fe atom. In the fifth O site, O is bonded in a single-bond geometry to one S atom. In the sixth O site, O is bonded in a single-bond geometry to one S atom. In the seventh O site, O is bonded in a single-bond geometry to one S atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on GaS5N5Cl4 by Materials Project

GaCl4(NS)5 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of eight GaCl4 clusters and eight NS clusters. In each GaCl4 cluster, Ga3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are two shorter (2.20 Å) and two longer (2.21 Å) Ga–Cl bond lengths. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Ga3+ atom. In each NS cluster, there are five inequivalent N+2.20+ sites. In the first N+2.20+ site, N+2.20+ is bonded in a linear geometry to two S2- atoms. Both N–S bond lengths are 1.56 Å. In the second N+2.20+ site, N+2.20+ is bonded in a bent 120 degrees geometry to two S2- atoms. Both N–S bond lengths are 1.59 Å. In the third N+2.20+ site, N+2.20+ is bonded in a bent 150 degrees geometry to two S2- atoms. There is one shorter (1.57 Å) and one longer (1.58 Å) N–S bond length. In the fourth N+2.20+ site, N+2.20+ is bonded in a bent 150 degrees geometry to two S2- atoms. There is one shorter (1.57 Å) and one longer (1.58 Å) N–S bond length. In the fifth N+2.20+ site, N+2.20+ is bonded in a linear geometry to two S2- atoms. Both N–S bond lengths are 1.56 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two N+2.20+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two N+2.20+ atoms. In the third S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms. In the fourth S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms. In the fifth S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Emerging Electrochemical Techniques for Probing Site Behavior in Single-Atom Electrocatalysts

Single-atom catalysts (SACs) have aroused tremendous interest over the past decade, particularly in the community of energy and environment-related electrocatalysis. A rapidly growing number of recent publications have recognized it as a promising candidate with maximum atomic utilization, distinct activity, and selectivity in comparison to bulk catalysts and nanocatalysts. However, the complexity of localized coordination environments and the dispersion of isolated sites lead to significant difficulties when it comes to gaining insight into the intrinsic behavior of electrocatalytic reactions. Furthermore, the low metal loadings of most SACs make conventional ensemble measurements less likely to be accurate on the subnanoscale. Thus, it remains challenging to probe the activity and properties of individual atomic sites by available commercial instruments and analytical methods. In spite of this, continuing efforts have lately focused on the development of advanced measurement methodologies, which are very useful to the fundamental understanding of SACs. There have recently been a number of in situ/operando techniques applied to SACs, such as electron microscopy, spectroscopy, and other analysis methods, which support relevant functions to identify the active sites and reaction intermediates and to investigate the dynamic behavior of localized structures of the catalytic sites. This Account aims to present recent electrochemical probing techniques which can be used to identify single-atomic catalytic sites within solid supports. First, we describe the basic principles of molecular probe methods for the study and analysis of electrocatalytic site behavior. In particular, the in situ probing technique enabled by surface interrogation scanning electrochemical microscopy (SISECM) can measure the active site density and kinetic rate with high resolution. An alternative electrochemical probing technique is further demonstrated on the basis of single-entity electrochemistry, which allows the unique electrochemical imaging of the size and catalytic rate of single atoms, molecules, and clusters. Next, the merits and limitations of different electrochemical techniques are then discussed, along with perspectives for future prospects. Apart from this, we further showcase the powerful capability of emerging electrochemical probing techniques for determining significant effects and properties of SACs for various electrocatalytic reactions, including oxygen reduction and evolution, hydrogen evolution, and nitrate reduction. Overall, electrochemical techniques with atomic resolution have greatly increased opportunities for observing, measuring, and understanding the surface and interface chemistry during energy conversion. In the future, it is anticipated that the development of electrochemical probing techniques will be advanced with innovative perspectives on the behavior and features of SACs. We hope that this Account can contribute in several ways to promoting the fundamental knowledge and technical progress of emerging electrochemical measurements for studying SACs.

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

Materials Data on As2Se2S(NF6)2 by Materials Project

N2Se2S(AsF6)2 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of eight AsF6 clusters and four N2Se2S clusters. In each AsF6 cluster, 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 six 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 As5+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one As5+ atom. In each N2Se2S cluster, there are two inequivalent N4+ sites. In the first N4+ site, N4+ is bonded in a bent 120 degrees geometry to one Se2- and one S2- atom. The N–Se bond length is 1.74 Å. The N–S bond length is 1.59 Å. In the second N4+ site, N4+ is bonded in a bent 120 degrees geometry to one Se2- and one S2- atom. The N–Se bond length is 1.74 Å. The N–S bond length is 1.59 Å. Se2- is bonded in a 1-coordinate geometry to one N4+ atom. S2- is bonded in a distorted water-like geometry to two N4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlSeS2N2Cl5 by Materials Project

AlCl4N2SeS2Cl crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four AlCl4 clusters and four N2SeS2Cl clusters. In each AlCl4 cluster, Al3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are a spread of Al–Cl bond distances ranging from 2.14–2.19 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In each N2SeS2Cl cluster, there are two inequivalent N4+ sites. In the first N4+ site, N4+ is bonded in a bent 120 degrees geometry to one Se2- and one S2- atom. The N–Se bond length is 1.78 Å. The N–S bond length is 1.59 Å. In the second N4+ site, N4+ is bonded in a bent 120 degrees geometry to two S2- atoms. There is one shorter (1.57 Å) and one longer (1.60 Å) N–S bond length. Se2- is bonded in a 2-coordinate geometry to one N4+ and one Cl1- atom. The Se–Cl bond length is 2.25 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a water-like geometry to two N4+ atoms. In the second S2- site, S2- is bonded in a distorted single-bond geometry to one N4+ atom. Cl1- is bonded in a single-bond geometry to one Se2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AlS5N5Cl4 by Materials Project

AlCl4(NS)5 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of eight AlCl4 clusters and eight NS clusters. In each AlCl4 cluster, Al3+ is bonded in a tetrahedral geometry to four Cl1- atoms. There are two shorter (2.16 Å) and two longer (2.17 Å) Al–Cl bond lengths. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Al3+ atom. In each NS cluster, there are five inequivalent N+2.20+ sites. In the first N+2.20+ site, N+2.20+ is bonded in a bent 120 degrees geometry to two S2- atoms. Both N–S bond lengths are 1.59 Å. In the second N+2.20+ site, N+2.20+ is bonded in a bent 150 degrees geometry to two S2- atoms. There is one shorter (1.57 Å) and one longer (1.58 Å) N–S bond length. In the third N+2.20+ site, N+2.20+ is bonded in a linear geometry to two S2- atoms. Both N–S bond lengths are 1.56 Å. In the fourth N+2.20+ site, N+2.20+ is bonded in a bent 150 degrees geometry to two S2- atoms. There is one shorter (1.57 Å) and one longer (1.58 Å) N–S bond length. In the fifth N+2.20+ site, N+2.20+ is bonded in a linear geometry to two S2- atoms. Both N–S bond lengths are 1.56 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms. In the second S2- site, S2- is bonded in a water-like geometry to two N+2.20+ atoms. In the third S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms. In the fourth S2- site, S2- is bonded in a water-like geometry to two N+2.20+ atoms. In the fifth S2- site, S2- is bonded in a bent 120 degrees geometry to two N+2.20+ atoms.

36 MATERIALS SCIENCE↗