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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
RbCo(CN)6(N(CH3)4)2 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional and consists of four tetramethylammonium molecules and one RbCo(CN)6 framework. In the RbCo(CN)6 framework, Rb1+ is bonded in an octahedral geometry to six N3- atoms. There are two shorter (3.14 Å) and four longer (3.30 Å) Rb–N bond lengths. Co1+ is bonded in an octahedral geometry to six C+0.14- atoms. There is two shorter (1.88 Å) and four longer (1.89 Å) Co–C bond length. There are five inequivalent C+0.14- sites. In the first C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–N bond length is 1.17 Å. In the second C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–Co bond length is 1.89 Å. The C–N bond length is 1.17 Å. In the third C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–N bond length is 1.17 Å. In the fourth C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–N bond length is 1.17 Å. In the fifth C+0.14- site, C+0.14- is bonded in a linear geometry to one Co1+ and one N3- atom. The C–Co bond length is 1.89 Å. The C–N bond length is 1.17 Å. There are five inequivalent N3- sites. In the first N3- site, N3- is bonded in a single-bond geometry to one Rb1+ and one C+0.14- atom. In the second N3- site, N3- is bonded in a single-bond geometry to one Rb1+ and one C+0.14- atom. In the third N3- site, N3- is bonded in a single-bond geometry to one Rb1+ and one C+0.14- atom. In the fourth N3- site, N3- is bonded in a single-bond geometry to one Rb1+ and one C+0.14- atom. The N–Rb bond length is 3.30 Å. In the fifth N3- site, N3- is bonded in a single-bond geometry to one Rb1+ and one C+0.14- atom. The N–Rb bond length is 3.30 Å. The N–C bond length is 1.17 Å.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Rb2CoS2 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to six equivalent S2- atoms. There are a spread of Rb–S bond distances ranging from 3.33–3.64 Å. Co2+ is bonded to four equivalent S2- atoms to form edge-sharing CoS4 tetrahedra. All Co–S bond lengths are 2.32 Å. S2- is bonded in a 2-coordinate geometry to six equivalent Rb1+ and two equivalent Co2+ atoms.
Rb2CoSe2 crystallizes in the orthorhombic Ibam space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. There are a spread of Rb–Se bond distances ranging from 3.51–3.68 Å. Co2+ is bonded to four equivalent Se2- atoms to form edge-sharing CoSe4 tetrahedra. All Co–Se bond lengths are 2.45 Å. Se2- is bonded in a 2-coordinate geometry to six equivalent Rb1+ and two equivalent Co2+ atoms.
This data package contains mean values for cation concentration for water samples taken from the East River Watershed in Colorado. Inductively coupled plasma mass spectrometry (ICP-MS) has been used to measure the concentrations of elements of interest simultaneously for the East River Watershed, Colorado groundwater and surface water samples to inform insights on the biogeochemistry processes within the watershed. The East River is part of the Watershed Function Scientific Focus Area (WFSFA) located in the Upper Colorado River Basin, United States. For samples collected prior to 06-16-2021, the instrumentation, Elan DRC II, PerkinElmer SCIEX, automatically switches among the three models necessary to analyze all 37 elements. These 37 elements include: (1) Lithium (Li), Beryllium (Be), Boron (B), Sodium (Na), Magnesium (Mg), Aluminium (Al), Silicon (Si), Phosphorus (P), Titanium (Ti), Cobalt (Co), Nickel (Ni), Copper (Cu), Zinc (Zn), Germanium (Ge), Arsenic (As), Rubidium (Rb), Strontium (Sr), Zirconium (Zr), Molybdenum (Mo), Silver (Ag), Cadmium (Cd), Tin (Sn), Antimony (Sb), Caesium (Cs), Barium (Ba), Europium (Eu), Lead (Pb), Thorium (Th), Uranium (U) using standard model, argon Ar as reaction gas, (2) Potassium (K), Calcium (Ca), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe) using dynamic reaction cell (DRC) model, ammonia NH3 as reaction gas, and (3) Phosphorus (P) and Selenium (Se) using DRC model, oxygen O2 as reaction gas. Note for the samples with higher concentrations of chloride (Cl-), asenic (As) concentrations were analysed with DRC model (oxygen O2 as reaction gas) to avoid the interference of chloride. For samples collected on and after 06-16-2021, an advanced Agilent 8900 triple quadrupole inductively coupled plasma mass spectrometry system (Agilent 8900 QQQ ICP-MS, Agilent Technologies) has been used to measure the concentrations of interested 36 elements simultaneously for environmental samples, including (1) Lithium (Li), Beryllium (Be) and Boron (B) using standard no gas mode, (2) Sodium (Na), Magnesium (Mg), Aluminium (Al) Phosphorus (P), Potassium (K), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), Zinc (Zn), Germanium (Ge), Arsenic (As), Rubidium (Rb), Strontium (Sr), Zirconium (Zr), Molybdenum (Mo), Silver (Ag), Cadmium (Cd), Tin (Sn), Antimony (Sb), Cesium (Cs), Barium (Ba), Europium (Eu), Lead (Pb), Thorium (Th) and Uranium (U) using standard helium (He) collision mode, (3) Titanium (Ti) and Vanadium (V) using high Energy (HEHe) helium (He) collision mode, and (4) Silicon (Si), Calcium (Ca) and Selenium (Se) using standard H2 reaction mode. All samples were prepared/diluted with 2% (v/v) ultrapure nitric acid in Milli-Q water (18.2 mega ohm-cm), and analyzed under a rigorous quality assurance and quality control (QA/QC) process. This data package contains (1) a zip file (cation_data_2014_2025.zip) containing a total of 5,849 files: 5.848 data files of cation data from across the Lawrence Berkeley National Laboratory (LBNL) Watershed Function Scientific Focus Area (SFA) which is reported in .csv files per location and a locations.csv (1 file) with latitude and longitude for each location; (2) a file-level metadata (v6_20260901_flmd.csv) file that lists each file contained in the dataset with associated metadata; (3) a data dictionary (v6_20260901_dd.csv) file that contains terms/column_headers used throughout the files along with a definition, units, and data type; (4) PDF and docx files for the detemination of Method Detection Limits (MDLs) for ICP-MS PerkinElmer DRC II instrumentation (Detemination_of_Method_Detection_Limits__MDLs__for_ICP_MS__PerkinElmer_Elan_DRC_II__LBL_Bldg74_Lab214D) for samples before November 2021; (5) PDF and docx files for the determination of MDLs for ICP-MS Agilent 8900 QQQ instrumentation (ICP_MS_Analysis_detection_limits_and_QA_QC_WenmingDong_updated_2026-08-06) for samples November 2021 and onward. Missing values within the anion data files are noted as either "-9999" or "0.0" for not detectable (N.D.) data. There are a total of 113 locations containing cation data. Update on 2021-04-11: Added Detemination of Method Detection Limits (MDLs) for ICP-MS document, which can be accessed as a PDF or with Microsoft Word. Update on 2022-06-10: versioned updates to this dataset was made along with these changes: (1) updated cation data for all locations up to 2021-12-31, (2) removal of units from column headers in datafiles, (3) added row underneath headers to contain units of variables, (4) removed suffix and prefix on two variables (“aqberylliumion_asberyllium” and “aqlithiumion_aslithium”), (5) added -9999 for empty numerical cells, and (6) the addition of the file-level metadata (flmd.csv) and data dictionary (dd.csv) were added to comply with the File-Level Metadata Reporting Format. Update on 2022-09-09: Updates were made to reporting format specific files (file-level metadata and data dictionary) to correct swapped file names, add additional details on metadata descriptions on both files, add a header_row column to enable parsing, and add version number and date to file names (v2_20220909_flmd.csv and v2_20220909_dd.csv). Update on 2023-08-08: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until 2023-01-05. The file level metadata and data dictionary files were updated to reflect the additional data added. Update on 2024-03-11: Updates were made to both the data files and reporting format specific files. New available anion data was added, up until 2023-10-16. Further, revisions to the data files were made to remove incorrect data points (from 1970 and 2001). The reporting format specific files were updated to reflect the additional data added. Updated versions of the PDF and docx files for determination of MDLs for ICP-MS data were added to this dataset for samples starting in November 2021. Update on 2025-05-15: Updates were made to both the data files and reporting format specific files. New available cation data was added, up until the end of WY2024 (September 30, 2024). International Generic Sample Numbers (IGSNs), when registered, were added to the data files. The reporting format specific files were updated to reflect the additional data added. Update on 2026-09-01: Updates were made to both the data files and reporting format specific files. New available cation data was added, up until the end of WY2025 (September 30, 2025). Updated versions, as of 2026-08-06, of the PDF and docx files for determination of MDLs for ICP-MS data were added to this dataset for samples starting in November 2021.
Eighteen achondrites and 4 terrestrial basalts (3 ocean ridge, 1 continental) were analyzed by radiochemical neutron activation analysis for Ag, Au, Bi, Br, Cd, Co, Cs, Cu, Ga, In, Ir, Rb, Se, Tl and Zn. Samples included 7 eucrites, 5 howardites, 2 nakhlites, 2 shergottites, an angrite, and an aubrite. Light and dark portions of the gas-rich meteorites Kapoeta and Pesyanoe were analyzed separately. Nakhlites and shergottites have volatile element abundances similar to those in ocean ridge basalts; eucrites, howardites, and angrites show greater depletions by an order of magnitude and less similar abundance patterns. In terms of a two-component model of planetary accretion, the parent planets contained the following percentages of low-temperature material: eucrites 0.8, nakhlites 38, shergottites 28. Shergottites may be genetically related to L-chondrites. The siderophile element pattern of achondrites resembles that of the moon, but with less extreme depletions.
RbMgO4Br3O2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of four hydrogen peroxide molecules and two RbMgO4Br3 sheets oriented in the (0, 1, 0) direction. In each RbMgO4Br3 sheet, Rb1+ is bonded in a 2-coordinate geometry to four O2- atoms. There are two shorter (2.80 Å) and two longer (3.24 Å) Rb–O bond lengths. Mg2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.00 Å) and two longer (2.02 Å) Mg–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Rb1+, one Mg2+, and one Br3+ atom. The O–Br bond length is 1.88 Å. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Rb1+, one Mg2+, and one Br3+ atom. The O–Br bond length is 1.81 Å. There are two inequivalent Br3+ sites. In the first Br3+ site, Br3+ is bonded in a linear geometry to two equivalent O2- atoms. In the second Br3+ site, Br3+ is bonded in a single-bond geometry to one O2- atom.
NiRb2NiC4(N2Cl)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of two nickel molecules and one Rb2NiC4(N2Cl)2 framework. In the Rb2NiC4(N2Cl)2 framework, Rb1+ is bonded in a square co-planar geometry to four equivalent Cl1- atoms. All Rb–Cl bond lengths are 3.56 Å. Ni2+ is bonded in an octahedral geometry to four equivalent N3- and two equivalent Cl1- atoms. All Ni–N bond lengths are 2.00 Å. Both Ni–Cl bond lengths are 2.53 Å. C2+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a linear geometry to one Ni2+ and one C2+ atom. Cl1- is bonded in a 5-coordinate geometry to four equivalent Rb1+ and one Ni2+ atom.
NiRb2NiC4(N2Br)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional and consists of two nickel molecules and one Rb2NiC4(N2Br)2 framework. In the Rb2NiC4(N2Br)2 framework, Rb1+ is bonded in a square co-planar geometry to four equivalent Br1- atoms. All Rb–Br bond lengths are 3.56 Å. Ni2+ is bonded in a distorted octahedral geometry to four equivalent N3- and two equivalent Br1- atoms. All Ni–N bond lengths are 2.00 Å. Both Ni–Br bond lengths are 2.72 Å. C2+ is bonded in a single-bond geometry to one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a linear geometry to one Ni2+ and one C2+ atom. Br1- is bonded to four equivalent Rb1+ and one Ni2+ atom to form a mixture of distorted edge and corner-sharing BrRb4Ni square pyramids.
The kagome Hubbard model (KHM) is a paradigmatic example of a frustrated two-dimensional model. While its strongly correlated regime, described by a Heisenberg model, is of topical interest due to its enigmatic prospective spin-liquid ground state, the weakly and moderately correlated regimes remain largely unexplored. Motivated by the rapidly growing number of metallic kagome materials (e.g., Mn 3 Sn, Fe 3 Sn 2 , FeSn, Co 3 Sn 2 S 2 , Gd 3 Ru 4 Al 12 , and AV 3 Sb 5 with A = K, Rb, Cs), here we study the respective regimes of the KHM by means of three complementary numerical methods: the dynamical mean-field theory, the dynamical vertex approximation, and determinant quantum Monte Carlo. In contrast to the archetypal square lattice, we find no tendencies toward magnetic ordering, as magnetic correlations remain short-range. Nevertheless, the magnetic correlations undergo a remarkable crossover as the system approaches the metal-to-insulator transition. The Mott transition itself does not affect the magnetic correlations. Our equal-time and dynamical structure factors can be used as a reference for inelastic neutron scattering experiments on the growing family of metallic kagome materials.
Nuclear materials, such as uranium-bearing solids, are exposed to high levels of ionizing radiation throughout the nuclear fuel cycle; thus, it is important to develop a molecular-level understanding of how these materials behave and degrade in the presence of gamma (γ) irradiation. In the current study, three U(VI) tetrachloride complexes, M 2 [UO 2 Cl 4 ]·xH 2 O (where M = K + , Rb + , or Cs + and x = 0 or 2), and their respective chloride salts were exposed to 1–50 kGy of γ radiation using a 60 Co source. Irradiated materials were evaluated by using electron paramagnetic resonance (EPR) and Raman spectroscopy and were further explored by using density functional theory (DFT) methods. EPR spectra of the irradiated materials suggest the formation of a Cl-based radical for both the alkali salts and the uranyl tetrachloride compounds, and DFT calculations provide evidence that the Cl 2 –• radical is formed within these materials. The presence of water in the K + and Rb + compounds leads to additional spectroscopic signatures that could be traced back to water radiolysis and the formation of peroxide and superoxide species. DFT results support the formation of HO 2 • in the lattice and potentially the formation of a [UO 2 Cl 3 (O 2 )] 3– species, highlighting the impact of water within the hydrated material to alter U(VI) speciation by radiolysis.
Rb2PtSe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. There are two shorter (3.52 Å) and four longer (3.58 Å) Rb–Se bond lengths. Pt2+ is bonded in a square co-planar geometry to four equivalent Se2- atoms. All Pt–Se bond lengths are 2.52 Å. Se2- is bonded in a 2-coordinate geometry to six equivalent Rb1+ and two equivalent Pt2+ atoms.
Rb2PdSe2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to six equivalent Se2- atoms. There are two shorter (3.55 Å) and four longer (3.56 Å) Rb–Se bond lengths. Pd2+ is bonded in a square co-planar geometry to four equivalent Se2- atoms. All Pd–Se bond lengths are 2.53 Å. Se2- is bonded in a 2-coordinate geometry to six equivalent Rb1+ and two equivalent Pd2+ atoms.
RbMg6BO7 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. Rb is bonded to six O atoms to form RbO6 octahedra that share corners with four equivalent RbO6 octahedra, edges with four equivalent MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 1°. There are four shorter (2.51 Å) and two longer (2.59 Å) Rb–O bond lengths. There are four inequivalent Mg sites. In the first Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with five MgO5 square pyramids, edges with four equivalent RbO6 octahedra, and edges with four equivalent MgO6 octahedra. There are one shorter (1.98 Å) and four longer (2.51 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with five MgO5 square pyramids and edges with four equivalent MgO6 octahedra. There are one shorter (1.99 Å) and four longer (2.51 Å) Mg–O bond lengths. In the third Mg site, Mg is bonded in a 2-coordinate geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 1.90–2.58 Å. In the fourth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with two equivalent RbO6 octahedra, edges with four equivalent MgO6 octahedra, and edges with four MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 3–26°. There are a spread of Mg–O bond distances ranging from 1.90–2.57 Å. B is bonded in a linear geometry to two O atoms. Both B–O bond lengths are 1.31 Å. There are five inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Rb, four equivalent Mg, and one B atom. In the second O site, O is bonded in a distorted single-bond geometry to one Rb, four equivalent Mg, and one B atom. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra and edges with four equivalent ORb2Mg4 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fourth O site, O is bonded to two equivalent Rb and four Mg atoms to form ORb2Mg4 octahedra that share corners with four equivalent ORb2Mg4 octahedra and edges with six OMg6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. In the fifth O site, O is bonded in a square co-planar geometry to four Mg atoms.
RbAgO2 crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Rb1+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Rb–O bond lengths are 3.02 Å. Ag3+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Ag–O bond lengths are 2.05 Å. O2- is bonded in a 2-coordinate geometry to four equivalent Rb1+ and two equivalent Ag3+ atoms.
Rb2PtS2 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Rb1+ is bonded in a 6-coordinate geometry to six equivalent S2- atoms. All Rb–S bond lengths are 3.44 Å. Pt2+ is bonded in a square co-planar geometry to four equivalent S2- atoms. All Pt–S bond lengths are 2.40 Å. S2- is bonded in a 2-coordinate geometry to six equivalent Rb1+ and two equivalent Pt2+ atoms.
RbCoO2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Rb–O bond distances ranging from 2.87–3.43 Å. In the second Rb1+ site, Rb1+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Rb–O bond distances ranging from 2.82–3.20 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to four O2- atoms to form corner-sharing CoO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.81–1.96 Å. In the second Co3+ site, Co3+ is bonded to four O2- atoms to form corner-sharing CoO4 tetrahedra. There are a spread of Co–O bond distances ranging from 1.79–1.95 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Rb1+ and two Co3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three equivalent Rb1+ and two Co3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to three Rb1+ and two equivalent Co3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Rb1+ and two equivalent Co3+ atoms.