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At least 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Superior Metal‐Organic Framework Activation with Dimethyl Ether

Abstract Metal–organic frameworks (MOFs) are demonstrated to be readily activated by treatment with the low surface tension, low boiling point solvent dimethyl ether (DME). The mildness of the method enables access to high surface areas by avoiding structural changes in the framework that often plague thermal activation methods. A distinction from previous methods is that DME activation succeeds for materials with coordinatively unsaturated sites (CUS) and non‐CUS MOFs as well. DME displaces solvent molecules occupying the pores of the MOF as well as those coordinated to metal centers; reducing evacuation temperature by using a coordinating, yet highly volatile guest enables low temperature activation with structural retention as demonstrated surface area measurements that match or exceed existing activation protocols.

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

Impact of Solution Chemistry on Growth and Structural Features of Mo-Substituted Spinel Iron Oxides

The effect of crystallizing solution chemistry on the chemistry of subsequently as-grown materials was investigated for Mo-substituted iron oxides prepared by thermally activated co-precipitation. In the presence of Mo ions, we find that varying the oxidation state of the iron precursor from Fe(II) to Fe(III) causes a progressive loss of atomic long-range order with the stabilization of 2-4 nm particles for the sample prepared with Fe(III). The oxidation state of the Fe precursor also affects the distribution of Fe and Mo cations within the spinel structure. Increasing the Fe precursor oxidation state gives decreased Fe-ion occupation and increased Mo-ion occupation of tetrahedral sites, as revealed by the extended X-ray absorption fine structure. The stabilization of Mo within tetrahedral sites appears to be unexpected, considering the octahedral preferred coordination number of Mo(VI). The analysis of the atomic structure of the sample prepared with Fe(III) indicates a local ordering of vacancies and that the occupation of tetrahedral sites by Mo induces a contraction of the interatomic distances within the polyhedra as compared to Fe atoms. Moreover, the occupancy of Mo into the thermodynamic site preference of a Mo dopant in Fe 2 O 3 assessed by density functional theory calculations points to a stronger preference for Mo substitution at octahedral sites. Hence, we suggest that the synthetized compound is thermodynamically metastable, that is, kinetically trapped. Such a state is suggested to be a consequence of the tetrahedral site occupation by Mo ions. The population of these sites, known to be reactive sites enabling particle growth, is concomitant with the stabilization of very small particles. Furthermore, we confirmed our hypothesis by using a blank experiment without Mo ions, further supporting the impact of tetrahedral Mo ions on the growth of iron oxide nanoparticles. Our findings provide new insights into the relationships between the Fechemistry of the crystallizing solution and the structural features of the as-grown Mo-substituted Fe-oxide materials.

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

Unprecedented lattice volume expansion on doping stereochemically active Pb 2+ into uniaxially strained structure of CaBa 1- x Pb x Zn 2 Ga 2 O 7

Lone pair cations like Pb 2+ are extensively utilized to modify and tune physical properties, such as nonlinear optical property and ferroelectricity, of some specific structures owing to their preference to adopt a local distorted coordination environment. Here we report that the incorporation of Pb 2+ into the polar “114”-type structure of CaBaZn 2 Ga 2 O 7 leads to an unexpected cell volume expansion of CaBa 1- x Pb x Zn 2 Ga 2 O 7 (0 ≤ x ≤ 1), which is a unique structural phenomenon in solid state chemistry. Structure refinements against neutron diffraction and total scattering data and theoretical calculations demonstrate that the unusual evolution of the unit cell for CaBa 1- x Pb x Zn 2 Ga 2 O 7 is due to the combination of the high stereochemical activity of Pb 2+ with the extremely strained [Zn 2 Ga 2 O 7 ] 4- framework along the c -axis. The unprecedented cell volume expansion of the CaBa 1- x Pb x Zn 2 Ga 2 O 7 solid solution in fact is a macroscopic performance of the release of uniaxial strain along c -axis when Ba 2+ is replaced with smaller Pb 2+ .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

The Zintl Concept Applied to Intergrowth Structures: Electron‐Hole Matching, Stacking Preferences, and Chemical Pressures in Pd 5 InAs

Abstract Enumerating the potential stacking sequences of layers is a fundamental way to account for the structure diversity of solid state compounds. In many cases, these stacking variations represent polymorphs with only small energetic differences. Here, we examine a compound for which the preferred stacking pattern instead reveals key aspects about its chemical bonding: Pd 5 InAs. Its structure is based on the intergrowth of slabs of the AuCu 3 and PtHg 2 (or alternatively, fluorite) structure types. Two basic stacking arrangements are available to this compound, represented by the Pd 5 TlAs and HoCoGa 5 structure types. DFT total energy calculations reveal that the former outcompetes the latter by a staggering 0.65 eV/formula unit. Through a combination of DFT‐reversed approximation Molecular Orbital (DFT‐raMO) and DFT‐Chemical Pressure (DFT‐CP) analysis we trace this preference to two factors. First, with DFT‐raMO analysis, we derive a Zintl‐like bonding scheme of Pd 5 InAs. This scheme, along with the inspection of selected crystal orbitals, is then connected to preferred stacking through the coordination environments of the Pd atoms at the interface between the Pd−In and Pd−As layers. In the hypothetical HoCoGa 5 ‐type and observed Pd 5 InAs‐type structures, different Pd coordination environments arise at the interfaces. The hypothetical structure features square planar PdIn 2 As 2 units, in each of which the same 4d‐orbital serves in the Pd sublattice's role as both Lewis acid (for interactions with the As) and Lewis base (for interactions with the In). In the observed structure, tetrahedral PdIn 2 As 2 units occur instead, so that these contradictory roles are distributed to separate 4d‐orbitals, leading to more effective bonding. DFT‐CP analysis illustrates that this driving force for the Pd 5 TlAs‐type arrangement is supplemented by a favorable alignment of the packing tensions in the parent structures. Altogether, the resulting picture demonstrates how the reaction of simple intermetallic structures to form intergrowths can be guided by recognizable chemical interactions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Deciphering supramolecular and polymer-like behavior in metallogels: real-time insights into temperature-modulated gelation and rapid self-assembly dynamics

Bis(pyridyl) urea-based gelators, namely L2 and its isomeric mixture ( L1 + L2 ), are known to self-assemble into 1D architectures capable of inducing supramolecular gelation. Coordination with metal ions such as Ag( I ), Cu( II ), and Fe( III ) introduces structural reinforcement, enabling the formation of distinct 3D networks governed by metal-specific coordination geometries. Here, we present a comprehensive investigation into the temperature-responsive behavior (20–60 °C) of L2 and L1 + L2 , both in the absence and presence of Ag( I ), Dy( III ), Fe( III ), Cu( II ), and Ho( III ), using real-time small-angle neutron scattering (SANS). To probe long-term structural evolution/kinetics of self-assembly, real-time small-angle X-ray scattering (SAXS) was employed on L2 + Ag gels, complemented by differential scanning calorimetry (DSC) to evaluate thermal transitions. Our results reveal strikingly divergent gelation behaviors: L2 forms a highly rigid, covalent polymer-like network, while L1 + L2 exhibits remarkable thermal adaptability. Upon metal coordination, the assemblies exhibit pronounced crystallinity and exceptional thermal stability, as evidenced by persistent Bragg reflections and invariant d-spacings. Intriguingly, L2 : Fe (2 : 1) and L1 : L2 : Fe (0.5 : 0.5 : 1) in acetonitrile-d 3 (ACN-d 3 ) deviate from this trend, forming thermally labile amorphous gels. These systems show a complete loss of crystalline order, reduced Porod exponents—indicative of collapsed or branched fiber morphologies—and prominent melting and glass transition events in DSC. Fitting SANS and SAXS data to the correlation length model unveiled insightful nanostructural features. While most systems displayed minimal temperature-induced variation in mesh size or surface morphology, L2 : Ag in dimethyl sulfoxide-d 6 (DMSO-d 6 )/D 2 O and L2 : Fe (1 : 1) in ACN-d 3 exhibited a rare combination of thermally stable correlation lengths and increasing high- q exponents—strongly suggesting progressive fiber densification or surface smoothing within a robust gel framework. These findings highlight the tunability and structural resilience of supramolecular gels through precise control of ligand architecture, metal coordination, and temperature, offering valuable design principles for functional soft materials.

Pajoubpong, Jinnipha [Univ. of Cincinnati, OH (Uni↗
DOE OSTI2021

Excited-state structural dynamics of nickel complexes probed by optical and X-ray transient absorption spectroscopies: insights and implications

Excited states of nickel complexes undergo a variety of photochemical processes, such as charge transfer, ligation/deligation, and redox reactions, relevant to solar energy conversion and photocatalysis. The efficiencies of the aforementioned processes are closely coupled to the molecular structures in the ground and excited states. The conventional optical transient absorption spectroscopy has revealed important excited-state pathways and kinetics, but information regarding the metal center, in particular transient structural and electronic properties, remains limited. These deficiencies are addressed by X-ray transient absorption (XTA) spectroscopy, a detailed probe of 3d orbital occupancy, oxidation state and coordination geometry. The examples of excited-state structural dynamics of nickel porphyrin and nickel phthalocyanine have been described from our previous studies with highlights on the unique structural information obtained by XTA spectroscopy. Furthermore, we close by surveying prospective applications of XTA spectroscopy to active areas of Ni-based photocatalysis based on the knowledge gained from our previous studies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Electrical and structural properties of binary Ga–Sb phase change memory alloys

Material properties of Ga–Sb binary alloy thin films deposited under ultra-high vacuum conditions were studied for analog phase change memory (PCM) applications. Crystallization of this alloy was shown to occur in the temperature range of 180–264 °C, with activation energy >2.5 eV depending on the composition. X-ray diffraction (XRD) studies showed phase separation upon crystallization into two phases, Ga-doped A7 antimony and cubic zinc-blende GaSb. Synchrotron in situ XRD analysis revealed that crystallization into the A7 phase is accompanied by Ga out-diffusion from the grains. X-ray absorption fine structure studies of the local structure of these alloys demonstrated a bond length decrease with a stable coordination number of 4 upon amorphous-to-crystalline phase transformation. Mushroom cell structures built with Ga–Sb alloys on ø110 nm TiN heater show a phase change material resistance switching behavior with resistance ratio >100 under electrical pulse measurements. TEM and Energy Dispersive Spectroscopy (EDS) studies of the Ga–Sb cells after ∼100 switching cycles revealed that partial SET or intermediate resistance states are attained by the variation of the grain size of the material as well as the Ga content in the A7 phase. A mechanism for a reversible composition control is proposed for analog cell performance. These results indicate that Te-free Ga–Sb binary alloys are potential candidates for analog PCM applications.

Ume, Rubab (ORCID:0000000324766900)↗
DOE OSTI2024

Deviatoric stress-induced metallization, layer reconstruction and collapse of van der Waals bonded zirconium disulfide

In contrast to two-dimensional (2D) monolayer materials, van der Waals layered transition metal dichalcogenides exhibit rich polymorphism, making them promising candidates for novel superconductor, topological insulators and electrochemical catalysts. Here, we highlight the role of hydrostatic pressure on the evolution of electronic and crystal structures of layered ZrS2. Under deviatoric stress, our electrical experiments demonstrate a semiconductor-to-metal transition above 30.2 GPa, while quasi-hydrostatic compression postponed the metallization to 38.9 GPa. Both X-ray diffraction and Raman results reveal structural phase transitions different from those under hydrostatic pressure. Under deviatoric stress, ZrS2 rearranges the original ZrS6 octahedra into ZrS8 cuboids at 5.5 GPa, in which the unique cuboids coordination of Zr atoms is thermodynamically metastable. The structure collapses to a partially disordered phase at 17.4 GPa. These complex phase transitions present the importance of deviatoric stress on the highly tunable electronic properties of ZrS2 with possible implications for optoelectronic devices.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Visualizing and analyzing 3D biomolecular structures using Mol* at RCSB.org: Influenza A H5N1 virus proteome case study

The easiest and often most useful way to work with experimentally determined or computationally predicted structures of biomolecules is by viewing their three-dimensional (3D) shapes using a molecular visualization tool. Mol* was collaboratively developed by RCSB Protein Data Bank (RCSB PDB, RCSB.org) and Protein Data Bank in Europe (PDBe, PDBe.org) as an open-source, web-based, 3D visualization software suite for examination and analyses of biostructures. It is capable of displaying atomic coordinates and related experimental data of biomolecular structures together with a variety of annotations, facilitating basic and applied research, training, education, and information dissemination. Across RCSB.org, the RCSB PDB research-focused web portal, Mol* has been implemented to support single-mouse-click atomic-level visualization of biomolecules (e.g., proteins, nucleic acids, carbohydrates) with bound cofactors, small-molecule ligands, ions, water molecules, or other macromolecules. RCSB.org Mol* can seamlessly display 3D structures from various sources, allowing structure interrogation, superimposition, and comparison. Using influenza A H5N1 virus as a topical case study of an important pathogen, we exemplify how Mol* has been embedded within various RCSB.org tools—allowing users to view polymer sequence and structure-based annotations integrated from trusted bioinformatics data resources, assess patterns and trends in groups of structures, and view structures of any size and compositional complexity. In addition to being linked to every experimentally determined biostructure and Computed Structure Model made available at RCSB.org, Standalone Mol* is freely available for visualizing any atomic-level or multi-scale biostructure at rcsb.org/3d-view.

3D biostructure↗
DOE OSTI2023

Molecular-dynamics simulation methods for macromolecular crystallography

It is investigated whether molecular-dynamics (MD) simulations can be used to enhance macromolecular crystallography (MX) studies. Historically, protein crystal structures have been described using a single set of atomic coordinates. Because conformational variation is important for protein function, researchers now often build models that contain multiple structures. Methods for building such models can fail, however, in regions where the crystallographic density is difficult to interpret, for example at the protein–solvent interface. To address this limitation, a set of MD–MX methods that combine MD simulations of protein crystals with conventional modeling and refinement tools have been developed. In an application to a cyclic adenosine monophosphate-dependent protein kinase at room temperature, the procedure improved the interpretation of ambiguous density, yielding an alternative water model and a revised protein model including multiple conformations. The revised model provides mechanistic insights into the catalytic and regulatory interactions of the enzyme. The same methods may be used in other MX studies to seek mechanistic insights.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Programmatic Equipment Procurement: An Improved System for Coordinating the Procurement of New Programmatic Equipment

A better structured system that outlines the communication required between the Project Manager (PM) and all the Key Stakeholders. This system will help the PM work with the SMEs to define the scope of the equipment to be procured. It will also help the PM confirm that all associated key stakeholders (WCI IT, FPOC, etc.) have been contacted and have reviewed the new equipment being proposed to be procured. This step is crucial in order to confirm that the piece of equipment being procured not only meets the SME requirements but also the security, safety and building requirements on site. This is a step that is currently missed or overlooked and can cause delays in procurement after the piece of equipment has already been decided on. This new system should help mitigate any delays or miscommunication regarding the piece of equipment being procured.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Crystalline 1D Coordination Polymer Inhibitor Layer Leads to Vertical Sidewalls in Selectively Deposited ZnO on Nanoscale Patterns

Area-selective atomic layer deposition (AS-ALD) is a promising technique for the fabrication of next-generation nanoelectronics. There are two main challenges in AS-ALD: (1) achieving high selectivity of deposition on the growth regions, and (2) preventing mushrooming of the growth material onto the nongrowth regions and achieving well-defined interfaces. In this work, we use benzenethiol (BT) as an inhibitor in the selective deposition of ZnO on SiO 2 in the presence of copper with and without a native oxide (Cu/CuO x ). We observe that BT forms a monolayer on the Cu surface and a Cu-thiolate multilayer structure on CuO x . Using grazing incidence X-ray diffraction combined with simulations, we find that the multilayer structure is crystalline and composed of 1D coordination polymers of Cu-thiolate. Here, using ellipsometry and X-ray photoelectron spectroscopy, we show that the BT consumes the entirety of the CuO x during multilayer formation, allowing the multilayer thickness to be tuned by the thickness of the original oxide. Both the monolayer BT and the multilayer BT prove to be effective inhibitors of ZnO ALD, blocking nearly 500 ALD cycles, which is more than twice that achieved with other thiol inhibitors. Finally, we demonstrate that the multilayer structure can prevent mushrooming of the ALD material onto the nongrowth surface of nanoscale patterns, creating vertical sidewalls with well-defined material interfaces and providing excellent pattern transfer, even for a relatively thick deposited film. As such, these results demonstrate that BT is not only an effective inhibitor but also that its ability to form tunable multilayers makes it well-suited for highly precise nanopatterning applications.

Layers↗
DOE OSTI2020

Materials Data on SrNb6O16 by Materials Project

SrNb6O16 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.59–2.76 Å. There are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and an edgeedge with one NbO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 4–51°. There are a spread of Nb–O bond distances ranging from 1.95–2.09 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with six NbO6 octahedra and an edgeedge with one NbO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 21–42°. There are a spread of Nb–O bond distances ranging from 1.87–2.18 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with six NbO6 octahedra and an edgeedge with one NbO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 16–51°. There are a spread of Nb–O bond distances ranging from 1.94–2.12 Å. In the fourth Nb5+ site, Nb5+ is bonded to seven O2- atoms to form NbO7 pentagonal bipyramids that share corners with two equivalent NbO7 pentagonal bipyramids and edges with five NbO6 octahedra. There are a spread of Nb–O bond distances ranging from 1.96–2.20 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Sr2+ and two equivalent Nb5+ atoms to form distorted corner-sharing OSr2Nb2 tetrahedra. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three Nb5+ atoms. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to three Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sr2+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Sr2+ and two equivalent Nb5+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two equivalent Nb5+ atoms. In the ninth O2- site, O2- is bonded in a linear geometry to two equivalent Nb5+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U(SiPt)2 by Materials Project

UPt2Si2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U4+ is bonded in a 8-coordinate geometry to eight Pt2- atoms. There are four shorter (3.20 Å) and four longer (3.27 Å) U–Pt bond lengths. There are two inequivalent Pt2- sites. In the first Pt2- site, Pt2- is bonded in a 5-coordinate geometry to four equivalent U4+ and five Si atoms. There are one shorter (2.39 Å) and four longer (2.42 Å) Pt–Si bond lengths. In the second Pt2- site, Pt2- is bonded to four equivalent U4+ and four equivalent Si atoms to form a mixture of distorted edge and face-sharing PtU4Si4 tetrahedra. All Pt–Si bond lengths are 2.49 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four equivalent Pt2- atoms to form a mixture of edge and corner-sharing SiPt4 tetrahedra. In the second Si site, Si is bonded in a 5-coordinate geometry to five Pt2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on CsIn5S8 by Materials Project

CsIn5S8 is Orthorhombic Perovskite-like structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Cs1+ is bonded in a 8-coordinate geometry to ten S2- atoms. There are a spread of Cs–S bond distances ranging from 3.56–4.09 Å. There are three inequivalent In3+ sites. In the first In3+ site, In3+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing InS6 octahedra. The corner-sharing octahedral tilt angles are 47°. There are two shorter (2.63 Å) and four longer (2.68 Å) In–S bond lengths. In the second In3+ site, In3+ is bonded to six S2- atoms to form a mixture of distorted corner, edge, and face-sharing InS6 octahedra. The corner-sharing octahedra tilt angles range from 41–61°. There are a spread of In–S bond distances ranging from 2.50–3.09 Å. In the third In3+ site, In3+ is bonded to six S2- atoms to form a mixture of corner, edge, and face-sharing InS6 octahedra. The corner-sharing octahedra tilt angles range from 41–61°. There are a spread of In–S bond distances ranging from 2.61–2.82 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two equivalent Cs1+ and three equivalent In3+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent Cs1+ and three In3+ atoms. In the third S2- site, S2- is bonded to one Cs1+ and four In3+ atoms to form a mixture of distorted corner and edge-sharing SCsIn4 trigonal pyramids. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to five In3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(IO3)2 by Materials Project

Hg(IO3)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Hg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Hg–O bond distances ranging from 2.25–2.97 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.84 Å) and one longer (2.60 Å) O–I bond lengths. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and two equivalent I5+ atoms. There are one shorter (1.83 Å) and one longer (2.71 Å) O–I bond lengths. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.79 Å) O–I bond lengths. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Hg2+ and two equivalent I5+ atoms. There are one shorter (1.84 Å) and one longer (2.66 Å) O–I bond lengths. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Hg2+ and one I5+ atom. The O–I bond length is 1.88 Å. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.64 Å) O–I bond lengths. There are two inequivalent I5+ sites. In the first I5+ site, I5+ is bonded to six O2- atoms to form distorted corner-sharing IO6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second I5+ site, I5+ is bonded in a 5-coordinate geometry to five O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbLi2(IO3)3 by Materials Project

RbLi2(O3I)3 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Rb1+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Rb–O bond distances ranging from 2.94–3.22 Å. There are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to four O2- atoms to form corner-sharing LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.95–2.05 Å. In the second Li1+ site, Li1+ is bonded to four O2- atoms to form corner-sharing LiO4 tetrahedra. There are a spread of Li–O bond distances ranging from 1.95–2.01 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.84 Å. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.83 Å. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one I5+ atom. The O–I bond length is 1.83 Å. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.82 Å. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.84 Å. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.84 Å. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Rb1+ and one I5+ atom. The O–I bond length is 1.85 Å. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Rb1+, two Li1+, and one I5+ atom. The O–I bond length is 1.84 Å. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Rb1+, one Li1+, and one I5+ atom. The O–I bond length is 1.83 Å. There are three inequivalent I5+ sites. In the first I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms. In the second I5+ site, I5+ is bonded in a 5-coordinate geometry to three O2- atoms. In the third I5+ site, I5+ is bonded in a 3-coordinate geometry to three O2- atoms.

36 MATERIALS SCIENCE↗