Peter C Burns

Peter C Burns
University of Notre Dame | ND · Department of Civil and Environmental Engineering and Earth Sciences

Ph.D.

About

699
Publications
70,646
Reads
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18,949
Citations
Citations since 2017
145 Research Items
6769 Citations
201720182019202020212022202302004006008001,0001,200
201720182019202020212022202302004006008001,0001,200
201720182019202020212022202302004006008001,0001,200
201720182019202020212022202302004006008001,0001,200
Additional affiliations
June 2002 - present
Argonne National Laboratory
Position
  • STA special term appointment
August 1997 - present
University of Notre Dame
Description
  • Massman Professor and Director, Energy Fronter Research Center
June 1995 - July 1996
University of New Mexico
Position
  • PostDoc Position
Education
January 1990 - May 1994
University of Manitoba
Field of study
  • Geology
September 1988 - December 1999
September 1984 - May 1988
University of New Brunswick
Field of study
  • Geology

Publications

Publications (699)
Article
We investigated the aqueous solubility and thermodynamic properties of two meta-autunite group uranyl arsenate solids (UAs). The measured solubility products (log Ksp) obtained in dissolution and precipitation experiments at equilibrium pH 2 and 3 for NaUAs and KUAs ranged from -23.50 to -22.96 and -23.87 to -23.38, respectively. The secondary phas...
Article
Metaschoepite, [(UO2)8O2(OH)12](H2O)10, maintained in a high relative humidity (RH) environment with air initially transformed into an intermediate phase that subsequently was replaced by the peroxide phase studtite, [(UO2)(O2)(H2O)2](H2O)2, over the course of 42 days, as observed using Raman and infrared spectroscopy and powder X-ray diffraction....
Article
Two uranium dioxide (UO2) targets of (414 ± 23) nm and (1092 ± 93) nm thicknesses were prepared on 6061 aluminum alloy and puratronic grade aluminum backing materials. The targets were deposited with a novel method combining spin coating and solution combustion synthesis (SCS). The target layers consisted of small (3–7 nm) UO2 grains and uniformly...
Article
Full-text available
Through the combination of low-temperature hydrothermal synthesis and room-temperature evaporation, a synthetic phase similar in composition and crystal structure to the Earth’s most complex mineral, ewingite, was obtained. The crystal structures of both natural and synthetic compounds are based on supertetrahedral uranyl-carbonate nanoclusters tha...
Article
The first actinide borosulfates, (UO2)[B(SO4)2(SO3OH)] (TSUBOS-1) and (UO2)2[B2O(SO4)3(SO3OH)2] (TSUBOB-1), were synthesized solvothermally in oleum using UO3. The classical borosulfate crystal structure of TSUBOS-1 is partially consistent with an established conventional hierarchy. Uranyl pentagonal bipyramids limit the anionic network linkages an...
Article
Spraying-assisted combustion synthesis with uranyl nitrate−acetylacetone−2-methoxyethanol solutions was used to prepare UO2 films on an aluminum alloy substrate. The tuning of the spraying parameters and annealing temperatures allowed the preparation of UO2 films with thicknesses varying from 10 – 300 nm and 5 − 10 nm UO2 grain size. High-resolutio...
Article
Aqueous solutions of lithium uranyl triperoxide, Li4[UO2(O2)3] (LiUT), were irradiated with gamma rays at room temperature and found to form the uranyl peroxide cage cluster, Li24[(UO2)(O2)(OH)]24 (Li-U24). Raman spectroscopy and 18O labeling were used to identify the Raman-active vibrations of LiUT. With these assignments, the concentration of LiU...
Article
Mechanochemistry enables transformations of highly insoluble materials such as uranium dioxide or the mineral studtite [(UO2)(O2)(H2O)2]·(H2O)2 into uranyl triperoxide compounds that can subsequently assemble into hydroxide-bridged uranyl peroxide dimers in the presence of lithium hydroxide. Dissolution of these solids in water yields uranyl peroxi...
Article
Four new hybrid organic‐inorganic uranyl phosphate compounds were structurally characterized after single crystals were grown via ionothermal synthesis using the ionic liquids 1‐ethyl‐3‐methylimidazolium dimethyl phosphate and 1‐ethyl‐3‐methylimidazolium dibutyl phosphate. Three of the new crystal structures presented here incorporate dimethyl or m...
Article
Finchite (IMA2017-052), Sr(UO2)2(V2O8)·5H2O, is the first U mineral known to contain essential Sr. The new mineral occurs as yellow-green blades up to ~10 µm in length in surface outcrops of the calcrete-type uranium deposit at Sulfur Springs Draw, Martin County, Texas, USA. Crystals of finchite were subsequently discovered underground in the Pando...
Article
The new mineral paramarkeyite (IMA2020–024), Ca2(UO2)(CO3)3·5H2O, was found in the Markey mine, San Juan County, Utah, USA, where it occurs as a secondary phase on gypsum-coated asphaltum in association with andersonite, calcite, gypsum and natromarkeyite. Paramarkeyite crystals are transparent, pale green-yellow, striated tablets, up to 0.11 mm ac...
Article
Seven new uranyl sulfate compounds with organic charge-balancing cations have been synthesized and structurally characterized. The structural unit topologies of the two chains and five sheets have been previously reported in uranyl sulfate crystal chemistry, although they were synthesized using different organic molecules. With the inclusion of six...
Article
A Np(V) neptunyl metal-organic framework (MOF) with rod-shaped secondary building units was synthesized, characterized, and irradiated with γ rays. Single-crystal X-ray diffraction data revealed an anionic framework containing infinite helical chains of actinyl-actinyl interaction (AAI)-connected neptunyl ions linked together through tetratopic tet...
Article
Structures of 388 neptunium-bearing crystal structures are sorted into an expanded structural hierarchy and examined. The majority of structures contain Np(V) (149), Np(VI) (99), or Np(IV) (91) whereas structures containing Np(II), Np(III), Np(VII), or more than one oxidation state are rare. Coordination geometry of Np(V) and Np(VI) compounds is do...
Article
The description of the energy landscape of polyoxometalates (POMs) enriches our understanding of their solution behavior through quantitative information that can be used to predict their existence, stability, and properties. Herein, we report thermodynamic values that describe the energy landscape of four uranyl peroxide nanoclusters (UPCs) (LiRb‐...
Article
Full-text available
Hydroxylpyromorphite, Pb5(PO4)3(OH), has been documented in the literature as a synthetic and naturally occurring phase for some time now but has not previously been formally described as a mineral. It is fully described here for the first time using crystals collected underground in the Copps mine, Gogebic County, Michigan. Hydroxylpyromorphite oc...
Article
The solution behavior of a polyoxometalate cluster, LiNa-U24Pp12 (Li24Na24[(UO2O2)24(P2O7)12]) that consists of 24 uranyl ions, peroxide groups, and 12 pyrophosphate linkers, was successfully predicted based on new thermodynamic results using a calorimetric method recently described for uranyl peroxide nanoclusters (UPCs), molybdenum blues, and mol...
Article
Two uranyl vanadate heteropolyoxometalates (h-POMs) have been synthesized by ionothermal methods using the ionic liquid 1-ethyl-3-methylimidazolium diethyl phosphate (EMIm-Et2PO4). The hybrid actinide-transition metal shell structures have cores of (UO2)8(V6O22) and (UO2)6(V3O12), which we designate as {U 8 V 6 } and {U 6 V 3 } , respecti...
Article
Because H2O2 is thermally unstable, it seems to be difficult to synthesize peroxides at elevated temperatures. We describe here the in situ generation of peroxide that is incorporated in a new uranyl peroxo complex, HT-UPO1, through the hydrothermal treatment of uranyl nitrate at 150 °C in the presence of organic ligands. In this novel process, a h...
Article
Seaborgite (IMA2019-087), LiNa6K2(UO2)(SO4)5(SO3OH)(H2O), is a new mineral species from the Blue Lizard mine, Red Canyon, San Juan County, Utah, U.S.A. It is a secondary phase found on gypsum in association with copiapite, ferrinatrite, ivsite, metavoltine, and römerite. Seaborgite occurs in sprays of light-yellow, long flattened prisms or blades,...
Article
Jeankempite, Ca 5 (AsO 4) 2 (AsO 3 OH) 2 (H 2 O) 7 , is a new mineral species (IMA 2018-090) discovered amongst coatings of arsenate minerals on oxidized copper arsenides from the Mohawk No. 2 mine, Mohawk, Keweenaw County, Michigan, USA. The new mineral occurs as lamellar bundles of colourless to white plates up to 1 mm in width and is visually in...
Article
Room temperature calorimetry methods were developed to describe the energy landscapes of six polyoxometalates (POMs), Li-U24, Li-U28, K-U28, Li/K-U60, Mo132, and Mo154, in terms of three components: enthalpy of dissolution (ΔHdiss), enthalpy of formation of aqueous POMs (ΔHf,(aq)), and enthalpy of formation of POM crystals (ΔHf,(c)). ΔHdiss is cont...
Article
The new minerals natromarkeyite, Na 2 Ca 8 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ⋅3H 2 O (IMA2018-152) and pseudomarkeyite, Ca 8 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ⋅3H 2 O (IMA2018-114) were found in the Markey mine, San Juan County, Utah, USA, where they occur as secondary phases on asphaltum. Natromarkeyite properties are: untwinned blades and tablets to 0.2...
Preprint
Full-text available
The new minerals natromarkeyite (IMA2018-152), Na 2 Ca 8 (UO 2) 4 (CO 3) 13 (H 2 O) 24 ·3H 2 O, and pseudomarkeyite (IMA2018-114), Ca 8 (UO 2) 4 (CO 3) 12 (H 2 O) 18 ·3H 2 O, were found in the Markey mine, San Juan County, Utah, USA, where they occur as secondary phases on asphaltum. Natromarkeyite properties: untwinned blades and tablets to 0.2 mm...
Article
A thorium-organic framework (TOF-16) containing hexameric secondary building units connected by functionalized binaphthol linkers was synthesized, characterized, and irradiated to probe its radiation resistance. Radiation stability was examined using γ-rays and 5 MeV He2+ ions to simulate alpha particles. γ-irradiation of TOF-16 to an unprecedented...
Article
Benzene-1,2-diphosphonic acid (Ppb) was introduced into the uranyl peroxide cluster system, resulting in three Ppb-functionalized uranyl peroxide clusters, (UO2)20(O2)20(C6H4P2O6)1040- (U20Ppb10), (UO2)26(O2)33(C6H4P2O6)638- (U26Ppb6), and (UO2)20(O2)24(C6H4P2O6)632- (U20Ppb6). Dissolution experiments were performed for the potassium salts of U20Pp...
Article
Neptunium poses challenges for radioactive wastes management due to its long half-life and ingrowth from americium decay, as well as its high mobility in water in its oxidized forms. Np(V)-bearing aqueous solutions were contacted with polished and crushed gneiss and dolerite from the Yeniseisky site, Russia, which is under consideration as a locati...
Article
Two uranium(IV) sulfate framework compounds were crystallized at room temperature from aqueous solutions containing uranyl ions by photochemical reduction in the presence of 2-propanol. U3H2(SO4)7(H2O)5·3H2O (1) crystallizes in space group P65 with a = 9.3052(17) Å, c = 53.515(10) Å, V = 4012.9(13) Å3, and Z = 6, and U3(UO2)0.2(SO4)6(OH)0.4·2.3H2O...
Article
Kroupaite (IMA2017-031), ideally KPb0.5[(UO2)8O4(OH)10]·10H2O, is a new uranyl-oxide hydroxyl-hydrate mineral found underground in the Svornost mine, Jáchymov, Czechia. Electron-probe microanalysis (WDS) provided the empirical formula (K1.28Na0.07)Σ1.35(Pb0.23Cu0.14Ca0.05Bi0.03Co0.02Al0.01)Σ0.48[(UO2)7.90(SO4)0.04O4.04(OH)10.00]·10H2O, basis of 40...
Article
Actinide phosphate materials with autunite or meta-autunite type sheets consisting of vertex-sharing actinyl square bipyramids and phosphate tetrahedra have low aqueous solubility and potential applications for actinide immobilization in the environment. Neptunyl phosphates, X(NpO2)(PO4)(H2O)3, X = K⁺ and Rb⁺, have been synthesized by hydrothermal...
Article
Full-text available
This study reports trace element abundances and Pb, Sr, and U isotopic signatures of uraninite from a variety of ore deposits in order to establish baseline forensic information for source attribution of raw, natural U-rich samples. Trace element concentrations, reported here, provide insights into uraninite crystal substitution mechanisms and poss...
Article
Conformational changes of the pyrophosphate (Pp)-functionalized uranyl peroxide nanocluster [(UO2)24(O2)24(P2O7)12]48- ({U24Pp12}), dissolved as a Li/Na salt, can be induced by the titration of alkali cations into solution. The most symmetric conformer of the molecule has idealized octahedral (O h ) molecular symmetry. One-dimensional 31P NMR exper...
Article
Uranyl phosphate minerals are widespread in uranium deposits and normally exhibit very low solubility in aqueous systems. Uranyl phosphates of the autunite group and metaautunite subgroup impact the mobility of uranium in the environment and have inspired groundwater remediation strategies that emphasize their low solubility. The importance of solu...
Article
Invited for the cover of this issue is research led by Pius Adelani at St. Mary's University, San Antonio, Texas, in collaboration with scientists at the University of Notre Dame, Indiana, USA. The cover image shows the one‐pot in situ phosphonate ligand condensation reaction and serendipitous self‐assembly of high nuclearity uranyl cages. This res...
Article
The Front Cover shows two synthetic pathways for preparing uranyl coordination cages. The first pathway (left) involves a one‐pot in situ condensation of the phosphonate to the pyrophosphonate ligand under mild hydrothermal conditions. This reaction is metal‐mediated and solvent‐driven to yield a sixteen membered uranyl coordination cage. The secon...
Article
Cs2[(AnO2)2(TO4)3] (where An = U, Np; T = S, Se, Cr, Mo) is a remarkable family of actinide-bearing compounds due to the surprising persistence of its structure type despite the substitutions in actinide and oxyanion sites. Cesium uranyl sulfate and selenate compounds have been analysed using high-temperature powder X-ray diffraction, Raman and lum...
Article
Full-text available
We report on the disparity in the assembly behavior of nano‐sized polyoxometalate (POM) and metal‐organic cage (MOC) macroions induced by isotopic substitution of Protium (H) to Deuterium (D) in solvents. Macroions with modest charge density can self‐assemble into single‐layer, hollow, spherical “blackberry”‐type structures at a lower rate in D2O t...
Article
The effects of radiation on a variety of uranyl peroxide compounds were examined using γ-rays and 5 MeV He ions, the latter to simulate α-particles. The studied materials were studtite, [(UO2)(O2)(H2O)2](H2O)2, the salt of the U60 uranyl peroxide cage cluster, Li44K16[(UO2)(O2)(OH)]60·255H2O, the salt of U60Ox30 uranyl peroxide oxalate cage cluster...
Article
We report an interesting phenomenon when interacting uranyl peroxide nanoclusters U60 (Li48+mK12(OH)m[UO2(O2)(OH)]60 (H2O)n, m≈20 and n≈310) with a small amount of cationic surfactants – the cationic surfactants do not distribute evenly around the U60 clusters during the interaction as expected. Instead, a small fraction of U60 clusters attract alm...
Conference Paper
Over the past decade, an average of well over 100 new minerals per year have been discovered and approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association. Exploration of abandoned mines and re-investigation of samples from classic localities have allowed mineralogists to discover mor...
Article
We report herein a general synthetic approach for designing uranyl coordination cages. Compounds 1 and 2 are constructed through a temperature-dependent and solvent-driven self-assembly. In both cases, the synthetic strategy involves in situ phosphonate ligand condensation into a flexible pyrophosphonate ligand. This pyrophosphonate ligand formatio...
Article
The ionic liquid 1-ethyl-3-methylimidazolium diethyl phosphate (EMIM-Et⁠2PO⁠4) was used in the synthesis of four new hybrid organic-inorganic uranyl phosphates. The structure of (UO⁠2)[PO⁠2(OC⁠2H⁠5)⁠2]⁠2 (1) is triclinic, P-1, a=5.374(3) Å, b=7.674(4) Å, c=11.132(6) Å, α=105.333(6)°, β=90.562(6)°, γ=98.269(6)°, Z=4. The structure of (C⁠6N⁠2H⁠11){(U...
Article
Full-text available
The chemical and isotopic (U, Pb, Sr) signatures for a suite (n = 23) of pristine (>80 wt. % UO2) and altered uraninite samples (>70–80 wt. % UO2) from various locations worldwide have been determined for the purpose of identifying potential fingerprints for nuclear forensic analysis. The characterization of the uraninite samples included determina...
Article
Little is known about the crystal chemistry of neptunyl peroxide compounds compared to uranyl peroxide compounds, for which dozens of structures have been described. Uranyl peroxides are formed over a broad range of pH and solution conditions, but neptunyl peroxide chemistry is complicated by the ability of H2O2 to act as an oxidizing or reducing a...
Article
Two phosphorylated cyclohexapeptides (CPs) bearing one (CP1) or two phosphates (CP2) were synthesized to explore the interactions between uranyl ions and very small cyclic peptides. According to the results of the ESI–MS and fluorescence titrations, the 1:1 uranyl-CPs complexes are the main products with the affinity constants of 7.3 × 10⁴ and 2.0...
Article
There is currently a lack of well‐characterised matrix‐matched reference materials (RMs) for forensic analysis of U‐rich materials at high spatial resolution. This study reports a detailed characterisation of uraninite (nominally UO2+x) from the Happy Jack Mine (Utah, USA). The Happy Jack uraninite can be used as a RM for determination of rare eart...
Article
An aromatic ligand was introduced into the synthesis of a uranyl peroxide polyoxometalate (POM) formulated as K32(UO2)19(O2)26(OH)2(C6H4P2O6)4⋅65 H2O that consists of a unique “open oyster” shaped structure (U19) with intramolecular H-bonds. In the solid state, K-π and π-π interactions, as well as K-O bonds enable the formation of a supramolecular...
Article
An isostructural series of Np(V) MOFs with shp-topology were synthesized and characterized. X-ray diffraction data revealed an unusual wheel-shaped node of eighteen neptunyl polyhedra stabilized in the framework. Strong distortion in local coordination of the neptunium atoms is evidenced by Np-Oyl bond lengths that lie outside the typical range for...
Article
Full-text available
Uranyl vanadate compounds with divalent cations, M(UO2)(V2O7) (M = Ca, Sr) and Sr3(UO2)(V2O7)2, were synthesized by flux crystal growth, and their crystal structures were solved using single-crystal X-ray diffraction data. Ca(UO2)V2O7 and Sr(UO2)V2O7 were synthesized from reactants with molar ratios M:U:V of 1:1:2 and identical heating conditions,...
Article
Single crystals of Rb2CaCu6(PO4)4O2 were synthesized by a hydrothermal method in the multicomponent system CuCl2–Ca(OH)2–RbCl–B2O3–Rb3PO4. The synthesis was carried out in the temperature range from 690 to 700 K and at the general pressure of 480-500 atm from the mixture in molar ratio 2CuO : CaO : Rb2O : B2O3 : P2O5. The crystals studied by single...
Article
The dissolution behavior of uranyl peroxide studtite, [(UO2)(O2)(H2O)2](H2O)2, was examined under a wide range of alkaline aqueous environments with and without the addition of hydrogen peroxide. In the absence of added H2O2, studtite dissolved in aqueous solutions with a tetraethylammonium hydroxide to uranium molar ratio greater than 0.5, and the...
Article
Aqueous solutions containing the nanoscale uranyl peroxide cage clusters U60, [(UO2)(O2)(OH)]6060-, and U60Ox30, [{(UO2)(O2)}60(C2O4)30]60-, were monitored by in situ Raman spectroscopy during stepwise heating to 180°C. In solutions containing U60, clusters persist to 120°C, although conversion of U60 to U24, [(UO2)(O2)(OH)]2424-, occurs above 100°...
Article
Dissolution of uranium materials in alkaline aqueous conditions containing H 2 O 2 results in uranyl peroxide species in solution, including anionic uranyl peroxide cage clusters. Uranyl peroxide cage clusters are generally highly soluble in water, where they persist as aqueous macroanions. Previous studies indicate that uranyl cluster speciation a...
Article
Single crystals of compounds based on novel microporous heteropolyhedral frameworks containing Ce and Er were synthesized hydrothermally and their structures were determined. The triclinic unit cell parameters of K7[Ce3(Si12O32)]⋅2H2O and K7[Er3(Si12O32)]⋅2H2O, respectively, are as follows: a = 6.9833(2), 6.8334(3) Å, b = 11.4171(3), 11.4474(3) Å,...
Article
The syntheses, characterization, and calorimetric measurements of enthalpies of formation of four tetravalent metal sulfate tetrahydrates (A ⁴⁺ (SO 4 ) 2 (H 2 O) 4 (A ⁴⁺ = Zr, Ce, U): α-Zr(SO 4 ) 2 (H 2 O) 4 , α-Ce(SO 4 ) 2 (H 2 O) 4 , β-Ce(SO 4 ) 2 (H 2 O) 4 , and β-U(SO 4 ) 2 (H 2 O) 4 )are reported. Direct calorimetric measurements showed that t...
Article
Phase formation in the mixed sulfate-selenate Np(VI)-bearing aqueous system has been investigated. The obtained crystalline compounds, Cs2[(NpO2)2(TO4)3] (T = S, Se), crystallize in the tetragonal system, P-421m, a = 9.5737(3)–9.817(3), c = 8.0824(4)–8.111(3) Å, V = 740.79(6)– 781.8(6) Å3, and have been chemically characterized. Single crystal X-ra...
Article
Novel red emitting phosphors Ca8MgSm1–х(PO4)7:xEu³⁺ with whitlockite-type structure were prepared by a high temperature solid-state reaction in air. Powder X-ray diffraction (PXRD), photoluminescence spectra, and fluorescence decay were used to characterize the structure and luminescence properties. All samples were found to have the expected rhomb...
Article
Five novel microporous uranyl germanates, Cs[(UO2)2(HGe2O7)] (1), Co2[(UO2)8(HGe2O7)4](H2O)6 (2), Ba2[(UO2)8(HGe2O7)4](H2O)3 (3), K4[(UO2)8(HGe2O7)4](H2O)2 (4), and Rb4[(UO2)8(HGe2O7)4](H2O)2 (5), have been synthesized under hydrothermal conditions. Single-crystal X-ray analyses indicate that 1 has an orthorhombic structure, space group Cmcm, while...
Article
Uranyl‐peroxide capsules are the newest family of polyoxometalates. Although discovered 13 years prior with over 70 topologies reported, we lack fundamental understanding of assembly mechanisms, particularly the role of the alkali countercations. Herein, we report the reaction pathway and assembly of uranyl peroxide capsules by tracking the convers...
Article
A novel hydrated magnesium uranyl germanate, Mg[(UO2)2(Ge2O6(OH)2)]∙(H2O)4.4, has been synthesized under hydrothermal conditions at 200 °C. The orthorhombic unit-cell parameters are a = 10.829(6), b = 7.625(4), c = 16.888(10) Å, V = 1394.5(1) Å3, space group Cmcm, Z = 4. The crystal structure is based on β-U3O8-type sheets of corner- and edge-shari...
Article
Two uranyl aqua sulfate compounds: [(CH3)3NCH2COOH] [UO2(Cl)(SO4)(H2O)] (1) and UO2((CH3)3NCH2COO)(SO4)(H2O) (2) were synthesized and their crystal structures were determined. The morphology changes between the two‐dimensional anionic structural unit of 1 and the neutral structural unit of 2 are examined, and the impact of their terminally coordina...
Article
A comparative investigation of the trace element, U and Pb isotopic compositions, and structural attributes of two uranium dioxide fuel pellets was conducted for nuclear forensic applications. One fuel pellet consists of natural UO2 (0.71% 235U), while the other contains enriched UO2 (3.98% 235U). Numerous impurities, including transition metals, l...
Article
Li and H2O encapsulated in the uranyl peroxide cage cluster U24 at 110 K are in square pyramidal and octahedral coordination, as dictated by the symmetry and topology of U24,...
Article
Full-text available
Crystal structure, thermal, dielectric and optical second harmonic activity were investigated for whitlockite-type Ca8.6Pb1.9(VO4)7 (1), Ca7Pb3.5(VO4)7 (2) and Ca5.6Pb4.9(VO4)7 (3) single crystals. The refinement of the structure revealed splitting of the М3 and М4 sites into two and three sub-positions respectively. Splitting of the М3 and М4 site...
Article
A new compound of the Rb1.5(NH4)0.5{Cu(P2O7)} composition, obtained by the high-temperature reaction method from a mixture of RbNO3, Cu(NO3)2, and (NH4)4P2O7, has been studied using X-ray diffraction. This compound is crystallized in the orthorhombic system, sp. gr. Pnma, a = 15.146(3) Å, b = 5.183(1) Å, c = 10.096(2) Å, V = 792.6(3) ų. The struct...
Article
A novel sodium and chromium borophosphate, obtained by hydrothermal synthesis in the Na2O–P2O5–B2O3–Cr2O3–Н2О system, has been investigated using X-ray diffraction and IR spectroscopy. The monoclinic cell parameters are found to be a = 10.4220(3) Å, b = 8.2468(2) Å, c = 9.2053(3) Å, β = 116.568(4)°, and V = 707.63(4) ų; sp. gr. С2/с. The structure...