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The many-body expansion for metals. I. The alkaline earth metals Be, Mg, and Ca

We examine the many-body expansion (MBE) for alkaline earth metal clusters, Be n , Mg n , Ca n ( n = 4, 5, 6), at the Møller–Plesset second order perturbation theory, coupled-cluster singles and doubles with perturbative triples, multi-reference perturbation theory, and multi-reference configuration interaction levels of theory. The magnitude of each term in the MBE is evaluated for several geometrical configurations. We find that the behavior of the MBE for these clusters depends strongly on the geometrical arrangement and, to a lesser extent, on the level of theory used. Another factor that affects the MBE is the in situ (ground or excited) electronic state of the individual atoms in the cluster. For most geometries, the three-body term is the largest, followed by a steady decrease in absolute energy for subsequent terms. Though these systems exhibit non-negligible multi-reference effects, there was little qualitative difference in the MBE when employing single vs multi-reference methods. Useful insights into the connectivity and stability of these clusters have been drawn from the respective potential energy surfaces and quasi-atomic orbitals for the various dimers, trimers, and tetramers. Through these analyses, we investigate the similarities and differences in the binding energies of different-sized clusters for these metals.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Materials Data on HgP2Xe5F22 by Materials Project

XeF2Hg(XeF2)4(PF6)2 crystallizes in the orthorhombic Pccn space group. The structure is zero-dimensional and consists of four Hg(XeF2)4 clusters, eight PF6 clusters, and four XeF2 clusters. In each Hg(XeF2)4 cluster, there are two inequivalent Xe sites. In the first Xe site, Xe is bonded in a linear geometry to two F atoms. There are one shorter (2.04 Å) and one longer (2.13 Å) Xe–F bond lengths. In the second Xe site, Xe is bonded in a linear geometry to two F atoms. There are one shorter (2.04 Å) and one longer (2.15 Å) Xe–F bond lengths. Hg is bonded in a 4-coordinate geometry to four F atoms. There are two shorter (2.30 Å) and two longer (2.36 Å) Hg–F bond lengths. There are four inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Xe atom. In the second F site, F is bonded in a distorted bent 120 degrees geometry to one Xe and one Hg atom. In the third F site, F is bonded in a single-bond geometry to one Xe atom. In the fourth F site, F is bonded in a bent 150 degrees geometry to one Xe and one Hg atom. In each PF6 cluster, P is bonded in an octahedral geometry to six F atoms. There are a spread of P–F bond distances ranging from 1.63–1.67 Å. There are six inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one P atom. In the second F site, F is bonded in a single-bond geometry to one P atom. In the third F site, F is bonded in a single-bond geometry to one P atom. In the fourth F site, F is bonded in a single-bond geometry to one P atom. In the fifth F site, F is bonded in a single-bond geometry to one P atom. In the sixth F site, F is bonded in a single-bond geometry to one P atom. In each XeF2 cluster, Xe is bonded in a linear geometry to two equivalent F atoms. Both Xe–F bond lengths are 2.08 Å. F is bonded in a single-bond geometry to one Xe atom.

36 MATERIALS SCIENCE↗

Revealing the Phase Separation Behavior of Thermodynamically Immiscible Elements in a Nanoparticle

Phase-separation is commonly observed in multimetallic nanomaterials, yet it is not well understood how immiscible elements distribute in a thermodynamically stable nanoparticle. Herein, we studied the phase-separation of Au and Rh in nanoparticles using electron microscopy and tomography techniques. The nanoparticles were thermally annealed to form thermodynamically stable structures. HAADF-STEM and EDS characterizations reveal that Au and Rh segregate into two domains while their miscibility is increased. Using aberration-corrected HAADF-STEM and atomic electron tomography, we show that the increased solubility of Au in Rh is achieved by forming Au clusters and single atoms inside the Rh domains and on the Rh surface. Furthermore, based on the three-dimensional reconstruction of a AuRh nanoparticle, we can visualize the uneven interface that is embedded in the nanoparticle. Finally, the results advance our understanding on the nanoscale thermodynamic behavior of metal mixtures, which is crucial for the optimization of multimetallic nanostructures for many applications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Materials Data on SbKr3F11 by Materials Project

Kr2F3KrF2SbF6 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Kr2F3 clusters, two KrF2 clusters, and two SbF6 clusters. In each Kr2F3 cluster, there are two inequivalent Kr sites. In the first Kr site, Kr is bonded in a linear geometry to two F atoms. There is one shorter (1.85 Å) and one longer (2.09 Å) Kr–F bond length. In the second Kr site, Kr is bonded in a linear geometry to two F atoms. There is one shorter (1.86 Å) and one longer (2.08 Å) Kr–F bond length. There are three inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Kr atom. In the second F site, F is bonded in a bent 150 degrees geometry to two Kr atoms. In the third F site, F is bonded in a single-bond geometry to one Kr atom. In each KrF2 cluster, Kr is bonded in a linear geometry to two equivalent F atoms. There is one shorter (1.93 Å) and one longer (1.94 Å) Kr–F bond length. F is bonded in a single-bond geometry to one Kr atom. In each SbF6 cluster, Sb is bonded in an octahedral geometry to six F atoms. There are a spread of Sb–F bond distances ranging from 1.91–1.93 Å. There are six inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. In the second F site, F is bonded in a single-bond geometry to one Sb atom. In the third F site, F is bonded in a single-bond geometry to one Sb atom. In the fourth F site, F is bonded in a single-bond geometry to one Sb atom. In the fifth F site, F is bonded in a single-bond geometry to one Sb atom. In the sixth F site, F is bonded in a single-bond geometry to one Sb atom.

36 MATERIALS SCIENCE↗

Materials Data on Sb2(KrF4)5 by Materials Project

(Kr2F3)2KrF2(SbF6)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight Kr2F3 clusters, four KrF2 clusters, and eight SbF6 clusters. In each Kr2F3 cluster, there are two inequivalent Kr sites. In the first Kr site, Kr is bonded in a linear geometry to two F atoms. There is one shorter (1.86 Å) and one longer (2.09 Å) Kr–F bond length. In the second Kr site, Kr is bonded in a linear geometry to two F atoms. There is one shorter (1.85 Å) and one longer (2.10 Å) Kr–F bond length. There are three inequivalent F sites. In the first F site, F is bonded in a bent 120 degrees geometry to two Kr atoms. In the second F site, F is bonded in a single-bond geometry to one Kr atom. In the third F site, F is bonded in a single-bond geometry to one Kr atom. In each KrF2 cluster, Kr is bonded in a linear geometry to two equivalent F atoms. There is one shorter (1.93 Å) and one longer (1.94 Å) Kr–F bond length. F is bonded in a single-bond geometry to one Kr atom. In each SbF6 cluster, Sb is bonded in an octahedral geometry to six F atoms. There is two shorter (1.92 Å) and four longer (1.93 Å) Sb–F bond length. There are six inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Sb atom. In the second F site, F is bonded in a single-bond geometry to one Sb atom. In the third F site, F is bonded in a single-bond geometry to one Sb atom. In the fourth F site, F is bonded in a single-bond geometry to one Sb atom. In the fifth F site, F is bonded in a single-bond geometry to one Sb atom. In the sixth F site, F is bonded in a single-bond geometry to one Sb atom.

36 MATERIALS SCIENCE↗

Materials Data on ReSbOF10 by Materials Project

Re2O2F9Sb2F11 is Tetraauricupride structured and crystallizes in the monoclinic P2 space group. The structure is zero-dimensional and consists of one Re2O2F9 cluster and one Sb2F11 cluster. In the Re2O2F9 cluster, Re7+ is bonded to one O2- and five F1- atoms to form distorted corner-sharing ReOF5 octahedra. The corner-sharing octahedral tilt angles are 8°. The Re–O bond length is 1.68 Å. There are a spread of Re–F bond distances ranging from 1.84–2.13 Å. O2- is bonded in a single-bond geometry to one Re7+ atom. There are five inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Re7+ atom. In the second F1- site, F1- is bonded in a linear geometry to two equivalent Re7+ atoms. In the third F1- site, F1- is bonded in a single-bond geometry to one Re7+ atom. In the fourth F1- site, F1- is bonded in a single-bond geometry to one Re7+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Re7+ atom. In the Sb2F11 cluster, Sb5+ is bonded to six F1- atoms to form corner-sharing SbF6 octahedra. The corner-sharing octahedral tilt angles are 2°. There is five shorter (1.90 Å) and one longer (2.08 Å) Sb–F bond length. There are six inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the third F1- site, F1- is bonded in a linear geometry to two equivalent Sb5+ atoms. In the fourth F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the fifth F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom. In the sixth F1- site, F1- is bonded in a single-bond geometry to one Sb5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on ZrP2NCl11 by Materials Project

ZrCl5P2NCl6 crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of eight P2NCl6 clusters and four ZrCl5 clusters. In each P2NCl6 cluster, P5+ is bonded to one N3- and three Cl1- atoms to form corner-sharing PNCl3 tetrahedra. The P–N bond length is 1.57 Å. There is one shorter (1.97 Å) and two longer (1.98 Å) P–Cl bond length. N3- is bonded in a bent 150 degrees geometry to two equivalent P5+ atoms. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one P5+ atom. In each ZrCl5 cluster, Zr4+ is bonded to six Cl1- atoms to form edge-sharing ZrCl6 octahedra. There are a spread of Zr–Cl bond distances ranging from 2.41–2.68 Å. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Zr4+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Zr4+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Al12Ge(Se2O35)2 by Materials Project

Al12GeO36(SeO4)2(SeO3)2(O2)10 crystallizes in the monoclinic C2 space group. The structure is zero-dimensional and consists of eight oxygen molecules, six trioxidane molecules, six water molecules, two Al12GeO36 clusters, four SeO3 clusters, and four SeO4 clusters. In each Al12GeO36 cluster, there are six inequivalent Al sites. In the first Al site, Al is bonded in a distorted square co-planar geometry to four O atoms. There are a spread of Al–O bond distances ranging from 1.77–1.85 Å. In the second Al site, Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.81–2.41 Å. In the third Al site, Al is bonded to five O atoms to form distorted AlO5 trigonal bipyramids that share a cornercorner with one AlO5 trigonal bipyramid and an edgeedge with one AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.83–1.89 Å. In the fourth Al site, Al is bonded to five O atoms to form distorted AlO5 trigonal bipyramids that share a cornercorner with one GeO4 tetrahedra, a cornercorner with one AlO5 trigonal bipyramid, and an edgeedge with one AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.79–1.97 Å. In the fifth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one GeO4 tetrahedra, an edgeedge with one AlO6 octahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.82–2.06 Å. In the sixth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one GeO4 tetrahedra, an edgeedge with one AlO6 octahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.83–2.00 Å. Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with four AlO6 octahedra and corners with two equivalent AlO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. There is two shorter (1.75 Å) and two longer (1.81 Å) Ge–O bond length. There are eighteen inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In the second O site, O is bonded in a water-like geometry to two Al atoms. In the third O site, O is bonded in a single-bond geometry to one Al atom. In the fourth O site, O is bonded in a water-like geometry to two Al atoms. In the fifth O site, O is bonded in a water-like geometry to two Al atoms. In the sixth O site, O is bonded in a water-like geometry to two Al atoms. In the seventh O site, O is bonded in a water-like geometry to two Al atoms. In the eighth O site, O is bonded in a trigonal planar geometry to two Al and one Ge atom. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Al and one Ge atom. In the tenth O site, O is bonded in a single-bond geometry to one Al atom. In the eleventh O site, O is bonded in a single-bond geometry to one Al atom. In the twelfth O site, O is bonded in a single-bond geometry to one Al atom. In the thirteenth O site, O is bonded in a single-bond geometry to one Al atom. In the fourteenth O site, O is bonded in an L-shaped geometry to two equivalent Al atoms. In the fifteenth O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the sixteenth O site, O is bonded in a water-like geometry to two Al atoms. In the seventeenth O site, O is bonded in a water-like geometry to two Al atoms. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In each SeO3 cluster, Se is bonded in a trigonal planar geometry to three O atoms. All Se–O bond lengths are 1.63 Å. There are three inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In each SeO4 cluster, Se is bonded in a tetrahedral geometry to four O atoms. There are a spread of Se–O bond distances ranging from 1.65–1.75 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Se atom. In the second O site, O is bonded in a single-bond geometry to one Se atom. In the third O site, O is bonded in a single-bond geometry to one Se atom. In the fourth O site, O is bonded in a single-bond geometry to one Se atom.

36 MATERIALS SCIENCE↗

Materials Data on TeC4S4N8(ClO4)2 by Materials Project

C2Te(N2S)2(CN2SO)2(ClO3)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two C2Te(N2S)2 clusters, four CN2SO clusters, and four ClO3 clusters. In each C2Te(N2S)2 cluster, there are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.31 Å) C–N bond length. In the second C4+ site, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.29 Å) C–N bond length. There are four inequivalent N+0.75+ sites. In the first N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the second N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.58 Å. In the third N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the fourth N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.57 Å. Te4+ is bonded in a distorted bent 150 degrees geometry to two S2- atoms. There are one shorter (2.44 Å) and one longer (2.55 Å) Te–S bond lengths. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to one N+0.75+ and one Te4+ atom. In the second S2- site, S2- is bonded in a distorted bent 120 degrees geometry to one N+0.75+ and one Te4+ atom. In each CN2SO cluster, C4+ is bonded in a linear geometry to two N+0.75+ atoms. There is one shorter (1.18 Å) and one longer (1.31 Å) C–N bond length. There are two inequivalent N+0.75+ sites. In the first N+0.75+ site, N+0.75+ is bonded in a single-bond geometry to one C4+ atom. In the second N+0.75+ site, N+0.75+ is bonded in a distorted bent 120 degrees geometry to one C4+ and one S2- atom. The N–S bond length is 1.56 Å. S2- is bonded in a distorted bent 120 degrees geometry to one N+0.75+ and one O2- atom. The S–O bond length is 1.45 Å. O2- is bonded in a single-bond geometry to one S2- atom. In each ClO3 cluster, there are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.47 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.49 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.48 Å. Cl1- is bonded in a trigonal non-coplanar geometry to three O2- atoms.

36 MATERIALS SCIENCE↗

Regioselective Generation of Single‐Site Iridium Atoms and Their Evolution into Stabilized Subnanometric Iridium Clusters in MWW Zeolite

Abstract Preparation of supported metal catalysts with uniform particle size and coordination environment is a challenging and important topic in materials chemistry and catalysis. In this work, we report the regioselective generation of single‐site Ir atoms and their evolution into stabilized subnanometric Ir clusters in MWW zeolite, which are located at the 10MR window connecting the two neighboring 12MR supercages. The size of the subnanometric Ir clusters can be controlled by the post‐synthesis treatments and maintain below 1 nm even after being reduced at 650 °C, which cannot be readily achieved with samples prepared by conventional impregnation methods. The high structure sensitivity, size‐dependence, of catalytic performance in the alkane hydrogenolysis reaction of Ir clusters in the subnanometric regime is evidenced.

Liu, Lichen↗

Regioselective Generation of Single‐Site Iridium Atoms and Their Evolution into Stabilized Subnanometric Iridium Clusters in MWW Zeolite

Abstract Preparation of supported metal catalysts with uniform particle size and coordination environment is a challenging and important topic in materials chemistry and catalysis. In this work, we report the regioselective generation of single‐site Ir atoms and their evolution into stabilized subnanometric Ir clusters in MWW zeolite, which are located at the 10MR window connecting the two neighboring 12MR supercages. The size of the subnanometric Ir clusters can be controlled by the post‐synthesis treatments and maintain below 1 nm even after being reduced at 650 °C, which cannot be readily achieved with samples prepared by conventional impregnation methods. The high structure sensitivity, size‐dependence, of catalytic performance in the alkane hydrogenolysis reaction of Ir clusters in the subnanometric regime is evidenced.

Liu, Lichen↗

Manipulating and Probing Ultrafast Atomic and Molecular Dynamics (Final Report)

This program has focused on the exploration and control of dynamics in atoms, small molecules, clusters, and micro- or nano-structures following ultrafast excitation and/or driven by strong oscillating fields. In our principal experiments, gas phase atoms and molecules were exposed to short pulses of electromagnetic radiation with frequencies ranging from THz into the XUV spectral regions, and with durations from picoseconds to attoseconds. The pulses coherently induce and/or probe dynamics in the electronic, vibrational, and rotational degrees of freedom of the targets. The overarching goal of the various projects has been to exploit strong-field processes and/or implement novel ultrafast techniques for manipulating and probing coherent electronic and nuclear motion. Typically, the relevant system evolution occurs over attosecond to picosecond timescales. In doing so, we have gained a more complete picture of correlated multi-particle dynamics in atoms, molecules, and other complex systems and expanded the toolbox of useful techniques for manipulating and probing those dynamics. Grant funds were primarily used to: (i) pay salaries and fringe benefits for the PI and postdocs and stipends, tuition, and health care costs for graduate students; (ii) cover travel expenses for the PI, postdocs, and students to attend and participate in professional meetings, conferences, and workshops; and (iii) purchase research materials, supplies, and equipment required for experiments. The research resulted in the publication of 24 peer reviewed articles (including 1 in Nature Physics, 2 in Nature Communications, 7 in Physical Review Letters, and 12 in Physical Review A), and 4 PhD dissertations. The specific results from different funding periods are summarized separately in the main report.

74 ATOMIC AND MOLECULAR PHYSICS↗

Genesis of the periodic lattice distortions in the charge density wave state of 2 H- TaSe 2

Using high-energy x-ray diffraction and large-scale three-dimensonal structure modeling, we reveal the evolution of local lattice distortions in the archetypal charge density wave (CDW) system 2 H- TaSe 2 as it is cooled from its normal state above room temperature down to temperature where Ta atoms form a long-range ordered superstructure. In particular, we find that the structure is formed via a gradual in-plane clustering of Ta atoms exhibiting unusually short bonding distances already near room temperature, and not via a cooperative distortion of Ta atomic planes taking place at the critical ordering temperature. Our findings clarify the debated local symmetry and magnitude of the periodic lattice distortions in the CDW state of 2 H- TaSe 2 , and emphasize the role of locally correlated lattice distortions as a precursor of CDWs in low-dimensional solids. Further, we demonstrate an efficient experimental approach to study them.

36 MATERIALS SCIENCE↗

Materials Data on H5ClO6 by Materials Project

H5O2(H2O)4(HClO4)2H5O6ClClO4 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one molecular hydrogen;dihydrate molecule, four water molecules, one ClO4 cluster, one H5O6Cl cluster, and two HClO4 clusters. In the ClO4 cluster, there are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In the H5O6Cl cluster, there are five inequivalent H sites. In the first H site, H is bonded in a single-bond geometry to two O atoms. There is one shorter (1.00 Å) and one longer (1.71 Å) H–O bond length. In the second H site, H is bonded in a linear geometry to two O atoms. There is one shorter (1.20 Å) and one longer (1.24 Å) H–O bond length. In the third H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the fourth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.99 Å. In the fifth H site, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 0.98 Å. There are six inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one H and one Cl atom. The O–Cl bond length is 1.47 Å. In the third O site, O is bonded in a trigonal non-coplanar geometry to three H atoms. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to three H atoms. In the fifth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.49 Å. In the sixth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In one of the HClO4 clusters, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.44 Å. In the third O site, O is bonded in a distorted water-like geometry to one H and one Cl atom. The O–Cl bond length is 1.63 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In one of the HClO4 clusters, H is bonded in a single-bond geometry to one O atom. The H–O bond length is 1.00 Å. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.43 Å. In the fourth O site, O is bonded in a distorted water-like geometry to one H and one Cl atom. The O–Cl bond length is 1.64 Å. Cl is bonded in a tetrahedral geometry to four O atoms.

36 MATERIALS SCIENCE↗

Metal-organic frameworks for the adsorption and catalytic transformations of carbon dioxide

Novel crystalline porous materials known as metal-organic frameworks (MOFs) and methods for their synthesis are provided herein. The MOFs include a M6(μ3-OH)8(OH)8(μ2,η2-(O2C)2cyclam)8 cluster, and a metal atom coordinated to the one or more cyclam of the cluster, wherein M is Zr or Hf, and the metal atom is any one of Cu, Ni, Cr, Ru, Co, and Gd. The MOFs can be used as an adsorbent, alone or in a medium with other components, of CO2. The MOFs can also be used as a catalyst for the transformation of CO2 and epoxides to cyclic carbonates. The MOFs can also be used in the electrochemical catalytic reduction of CO2. The MOFs can also be used for photocatalytic CO2 reduction for the production of carbon-based fossil fuels. The MOFs can also be used for light-induced nitric oxide (NO) release. The MOFs can also be used as magnetic resonance imaging (MRI) agents.

Morris, Amanda Jean↗

Materials Data on CoC12N8(ClO5)2 by Materials Project

CoO4(C5N4)2(CO2)2(ClO)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two formic acid molecules, two C5N4 clusters, one ClO cluster, and one CoO4 cluster. In each C5N4 cluster, there are five inequivalent C+3.67+ sites. In the first C+3.67+ site, C+3.67+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.30 Å. In the second C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.32 Å) and one longer (1.42 Å) C–N bond length. In the third C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.39 Å) and one longer (1.58 Å) C–N bond length. In the fourth C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.32 Å) and one longer (1.40 Å) C–N bond length. In the fifth C+3.67+ site, C+3.67+ is bonded in a bent 120 degrees geometry to two N3- atoms. There is one shorter (1.35 Å) and one longer (1.38 Å) C–N bond length. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a bent 120 degrees geometry to two C+3.67+ atoms. In the second N3- site, N3- is bonded in a bent 120 degrees geometry to two C+3.67+ atoms. In the third N3- site, N3- is bonded in a 3-coordinate geometry to three C+3.67+ atoms. In the fourth N3- site, N3- is bonded in a water-like geometry to two C+3.67+ atoms. In the ClO cluster, O2- is bonded in a distorted L-shaped geometry to two equivalent Cl1- atoms. There is one shorter (1.56 Å) and one longer (2.33 Å) O–Cl bond length. Cl1- is bonded in a 2-coordinate geometry to two equivalent O2- atoms. In the CoO4 cluster, Co2+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.64 Å) and two longer (1.88 Å) Co–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Co2+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Co2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on H22RuN7(ClO2)4 by Materials Project

(RuN3H6)2(NH4)2(N3H12Cl)2(ClO4)4Cl2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two ammonium molecules, two hydrochloric acid molecules, four ClO4 clusters, two N3H12Cl clusters, and two RuN3H6 clusters. In each ClO4 cluster, there are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.46 Å. In the second O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.47 Å. In the third O2- site, O2- is bonded in a single-bond geometry to one Cl1- atom. The O–Cl bond length is 1.47 Å. Cl1- is bonded in a tetrahedral geometry to four O2- atoms. In each N3H12Cl cluster, there are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a tetrahedral geometry to four H1+ atoms. There is three shorter (1.03 Å) and one longer (1.06 Å) N–H bond length. In the second N1- site, N1- is bonded in a tetrahedral geometry to four H1+ atoms. There is three shorter (1.03 Å) and one longer (1.07 Å) N–H bond length. There are seven inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N1- and one Cl1- atom. The H–Cl bond length is 2.07 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N1- and one Cl1- atom. The H–Cl bond length is 1.94 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. Cl1- is bonded in a distorted single-bond geometry to three H1+ atoms. In each RuN3H6 cluster, Ru5+ is bonded in a trigonal non-coplanar geometry to three N1- atoms. There is two shorter (1.88 Å) and one longer (1.94 Å) Ru–N bond length. There are two inequivalent N1- sites. In the first N1- site, N1- is bonded in a distorted trigonal planar geometry to one Ru5+ and two H1+ atoms. Both N–H bond lengths are 1.03 Å. In the second N1- site, N1- is bonded in a distorted trigonal non-coplanar geometry to one Ru5+ and two equivalent H1+ atoms. Both 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 N1- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N1- atom.

36 MATERIALS SCIENCE↗

A new non-diffusional gas bubble production route in used nuclear fuel: Implications for fission gas release, cladding corrosion, and next generation fuel design

The relationship between noble metal phase particles and fission gas bubble production in used nuclear fuel is described. The majority of Te atoms within noble metal phase undergo radioactive decay to form stable Xe within a few hours after particle formation. This results in the production of clusters of Xe atoms contained within the solid metal matrix exhibiting an equivalent gas bubble pressure approaching 1 GPa. These high pressure bubbles are stabilized by the UO2 within the bulk of the fuel. However, when these bubbles form near the fuel / cladding interface, in combination with local and temporal damage caused by fission recoil, they are capable of overcoming the fracture strength of the UO2 and rupturing catastrophically. The force of the resulting bubble rupture is sufficient to eject noble metal phase particles several microns into the cladding. This proposed mechanism explains the observance of noble metal phase in cladding and is consistent with a host of morphological features found near the fuel / cladding interface.

Schwantes, Jon M.↗