Vanadium(III) Solid

6 hours ago - Synopsis. The first heterobimetallic uranium(IV)/vanadium(III) phosphite compound, Na2UV2(HPO3)6 (UVP), was generated from an in situ re...
0 downloads 12 Views 1MB Size
Communication Cite This: Inorg. Chem. XXXX, XXX, XXX−XXX

pubs.acs.org/IC

An Ultrastable Heterobimetallic Uranium(IV)/Vanadium(III) Solid Compound Protected by a Redox-Active Phosphite Ligand: Crystal Structure, Oxidative Dissolution, and First-Principles Simulation Daxiang Gui,†,‡ Xing Dai,†,‡ Tao Zheng,†,‡ Xiangxiang Wang,† Mark A. Silver,† Lanhua Chen,† Chao Zhang,§ Juan Diwu,† Ruhong Zhou,⊥,∥ Zhifang Chai,† and Shuao Wang*,† †

School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Jiangsu 215123, China ⊥ Computational Biology Center, IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States ∥ Department of Chemistry, Columbia University, New York, New York 10027, United States § School of Materials Science and Engineering, Anhui University of Science and Technology, Huainan 232001, P. R. China S Supporting Information *

in waste repository science7 because phosphite has the ability to reduce the most prevalent actinides in nuclear waste to low oxidation states, which results in the formation of actinide phosphites that are insoluble. Although a few actinide phosphite compounds have been prepared, where these materials were synthesized through the use of organic ligands acting as reductants or templates, actinide phosphites have not been explored enough.8 Furthermore, uranium(IV) phosphites also containing transition metals in low oxidation states have never been achieved.9 In particular, it is the interaction between the unpaired 5f electrons in uranium(IV) and the unpaired d electrons in trivalent transition metals that would stir unique physical and chemical properties and are therefore sought-after.10 Herein, we introduce a new heterobimetallic uranium(IV)/ vanadium(III) phosphite, Na2UV2(HPO3)6 (UVP), which was prepared from a facile hydrothermal synthetic route (described in detail in the Supporting Information). In this reaction, uranium(IV) was generated from the in situ reduction of uranium(VI) and vanadium(III) from vanadium(V), with phosphite functioning as a reductant. Single-crystal X-ray diffraction (SC-XRD) analysis reveals that UVP crystallizes in the space group P3̅1m. Uranium and vanadium octahedra are bridged by phosphite groups, extending a porous three-dimensional framework containing Na+ cations in the void space to balance the charge (Figure 1a). The UO6 unit in UVP consists of a uranium metal center coordinated by one crystallographically unique oxygen site from six monodentate phosphite groups, thereby forming a symmetric octahedral coordination environment (Figure 1b). Using the six U−O bond distances of 2.220(4) Å, the bond-valence sum of this uranium site is determined to be 4.05 valence units. The presence of uranium(IV) in UVP is particularly stirring considering the reaction conditions used and the coordination geometry in UVP that rarely occurs for uranium(IV). Vanadium is coordinated in a manner similar to that of uranium, by one crystallographically unique oxygen site from six phosphite groups, and is coordinated in octahedral environments as a result (Figure 1c). The bond-

ABSTRACT: The first heterobimetallic uranium(IV)/ vanadium(III) phosphite compound, Na2UV2(HPO3)6 (denoted as UVP), was synthesized via an in situ redoxactive hydrothermal reaction. It exhibits superior hydrolytic and antioxidant stability compared to the majority of structures containing low-valent uranium or vanadium, further elucidated by first-principles simulations, and therefore shows potential applications in nuclear waste management.

T

he properties of uranium(IV) in the solid state have driven interest among actinide scientists because of their complex structures, peculiar electronic behavior, and magnetic properties, which are attributable to the large ionic radius and the two unpaired 5f electrons of uranium(IV).1 Binary uranium(IV) fluorides (i.e., UF4 and UF6) have been thoroughly investigated, while alkali-metal uranium(IV) fluorides and several transitionmetal uranium(IV) fluorides have been synthesized and reported.2 Many germinates and silicates containing uranium(IV) have been prepared via hydrothermal methods, but these processes demanded extremely high pressures and temperatures.3 Crystallizing uranium(IV) organometallic complexes typically requires the use of a wide variety of organic reductants (solvents); however, this synthetic method often leads to the crystal structures being incorporated into an organic group.4 Plenty of researches show that uranium(IV) is still easily oxidized to the much more soluble uranium(VI). This is even true for uranium dioxide (UO2), which is often oxidized to UO2+x under aerobic conditions. Consequently, it is still a challenge to achieve stable inorganic uranium(IV) compounds.5 It is well-known that actinide phosphate compounds have potential applications in geological waste repositories owing to their generally high thermal stability and low solubility.6 In comparison to phosphate, whose central phosphorus is pentavalent in these compounds, phosphite contains trivalent phosphorus, which is highly reducing and has also been found to bind tightly to actinides. This allows for redox chemistry to take place, a feature that qualifies phosphate as a solution to problems © XXXX American Chemical Society

Received: October 12, 2017

A

DOI: 10.1021/acs.inorgchem.7b02623 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry

vanadium(III) (3d2) (Figures S8). The room temperature χMT value per [UV2(HPO3)6]2− unit is 2.81 cm3 K mol−1, close to the theoretical value of 3.0 cm3 K mol−1 expected for two vanadium(III) ions (S = 1 and g = 2) and one uranium(IV) ion (S = 1). The susceptibility data above 50 K obey the Curie−Weiss law with C = 3.76 cm3 K mol−1 and θ = −120.75 K. The negative Weiss constant suggests an overall AF interaction among the metal ions. Upon cooling, the χMT value decreases continuously to 1.26 cm3 K mol−1 at 50 K and then rapidly reaches a minimum value of 0.08 cm3 K mol−1 at 2.0 K, originating from thermal depopulation of the Stark sublevels, the presence of significant magnetic anisotropy, and the overall AF interactions. The peak of the χM versus T plot at 4.89 K indicates strong AF interactions. Because the interaction of uranium ions is very weak due to efficient shielding of the unpaired 5f electrons and the magnetic exchange by the bridges of O−P−O is weak, the magnetic behavior is likely dominated by the vanadium dimers via V−O−V interactions.15 The magnetism is very similar to the case of H2KO6P2V containing comparable V−V distances and bond angles,16c which is summarized in Table S3 and Figure S4.16 Typically, uranium(IV), vanadium(III), and phosphorus(III) are unstable at ambient conditions because of their intrinsic tendencies to be oxidized.17 However, surprisingly, we found that UVP exhibits very good hydrolytic stability and even radiation resistance. Hydrolytic stability tests of UVP were carried out in aqueous solutions with pH values ranging from 0 to 14. Powder X-ray diffraction (PXRD) patterns were collected for all samples soaked in acidic or basic solutions, showing that UVP samples maintain good crystallinity in solution (Figure S5). Additionally, we observed no structural or crystal degradation for UVP when placed under 200 kGy 60Co γ irradiation with a dose rate of 1.2 kGy h−1 (Figures S6) while in solution with hydrogen peroxide, bolstering the resistance of UVP from radiation. The oxidative dissolution results show that UVP has significant acid−base and redox stability. As shown in Figure S6, the crystallinity of UVP can be completely maintained after treatment in a series of oxidizing solutions containing KMnO4, K2Cr2O7, or HNO3. Further investigation of the oxidative dissolution behavior of this mixed uranium(IV)/vanadium(III) phosphite was achieved using solubility studies in combination with inductively coupled plasma mass spectrometry (ICP-MS; Figure 3). Dissolution experiments with a solid/liquid ratio of 20 mg of UVP per 40 mL of oxidizing solution were conducted (see the Supporting Information for details). These experiments were conducted over a period of 40 days, with tests done intermittently throughout this time range. In the experiment that causes the largest dissolution rate (pH 2 with 0.01 mol L−1 KMnO4), less

Figure 1. (a) Overall framework structures of UVP, (b) a uranium(IV) cation, and (c) a vanadium(III) cation. Color scheme: U, yellow; V, green; O, red; P, blue; Na, purple.

valence sum for vanadium, when calculated using the V−O bond distance of 2.009(2) Å, is 2.92, revealing an unusual occurrence of vanadium(III) under aerobic conditions.11 Elemental analysis was performed using scanning electron microscopy and energy-dispersive spectroscopy (EDS). The U:V atomic ratio was determined to be 1:1.94, consistent with that found from crystallographic data (Figure S1 and Table S3). Meanwhile, the valence states of uranium(IV) and vanadium(III) in UVP were studied using X-ray photoelectron spectroscopy (XPS). The U 4f and V 2p XPS results were fitted with two components of uranium(IV) and vanadium(III) (Figure 2a,d). In

Figure 2. XPS spectrs and fittings for compound UVP. U 4f spectra of (a) UVP, (b) UVP at pH 2 with 0.01 mol L−1 KMnO4, and (c) UVP at pH 1 with 0.01 mol L−1 K2Cr2O7. V 2p spectra of (d) UVP, (e) UVP at pH 2 with 0.01 mol L−1 KMnO4, and (f) UVP at pH 1 with 0.01 mol L−1 K2Cr2O7. P 2p spectra of (g) UVP, (h) UVP at pH 2 with 0.01 mol L−1 KMnO4, and (i) UVP at pH 1 with 0.01 mol L−1 K2Cr2O7.

reference to the binding energies (BEs) of C 1s, the BEs of all of the peaks are at 285.0 eV. The BEs of uranium(IV) in UVP are located at 381.8 eV (U 4f7/2) and 392.7 eV (U 4f5/2), respectively, and are in good agreement with the BEs found in U(C2O4)2· 6H2O or UO2.12 Meanwhile, the BEs of the V 2p3/2 and 2p1/2 peaks appear at 517.8 and 524.6 eV, respectively, and compare well with those for vanadium(III) in V2O3.13 The BEs of the P 2p3/2 and 2p1/2 peaks appear at 133.4 and 134.7 eV, respectively, and compare well with those for phosphorus(III) in phosphite compounds.14 The antiferromagnetic (AF) feature of UVP is observed based on the paramagnetic centers of uranium(IV) (5f2) and

Figure 3. Time evolution of UVP oxidative dissolution experiments. B

DOI: 10.1021/acs.inorgchem.7b02623 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry

stored uranium(IV) is supported with these data because it has been shown that phosphite maintains this oxidation state for a meaningful length of time, regardless of the pH, and even in the presence of strong oxidants. In conclusion, the first mixed uranium(IV)/vanadium(III) phosphite compound was prepared via a redox-active hydrothermal reaction. Characterization via SC-XRD revealed uranium(IV) and vanadium(III) metal centers in the structure, where the stability of either tetravalent uranium or trivalent vanadium is uncommon to achieve in air-stable materials. UVP is a rare example of a uranium(IV) forming an octahedral coordination geometry, and initial investigations indicated a superior hydrolytic stability and antioxidant stability of UVP, as further elucidated through first-principles simulation investigations. Functionalities such as the waste form of actinides for geological disposal may be expected for UVP.

than 15% (based on uranium content) of the available UVP was dissolved and oxidized. Confirmatory XPS data were collected for samples after 40 days, and these corroborate the stability of both the uranium(IV) and vanadium(III) valence states in UVP (Figure 2b,c,e,f,h,i). However, XPS spectra collected on samples after dissolution also depict full maintenance of the uranium(IV) and vanadium(III) states in the solid. For the case treated with KMnO4, the phosphorus peaks slightly shift to the lower-energy region for ca. 1 eV, indicating that partial oxidation of phosphorus(III) to phosphorus(V) may occur at the crystal surface.18 In addition, thermogravimetric analysis (TGA) shows that UVP is stable up to 723 K (Figure S9). UVP offers a unique case where both tetravalent uranium and trivalent vanadium may be treated using density functional theory to investigate the electronic structure of these uncommon valence states (Figure 4a, left). The net spin density and orbital



ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.inorgchem.7b02623. Experimental methods and data for crystallography, absorption spectroscopy, EDS analysis, oxidative dissolution experiments and ICP-MS analysis, TGA, XPS analysis, magnetic susceptibility measurements, quantum mechanics and molecular dynamics simulations, and PXRD (PDF) Accession Codes

CCDC 1577631 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by emailing data_ [email protected], or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336033.

Figure 4. (a) Electronic structure of UVP. (b) Molecular orbital analyses of UVP. (c) Stability of UVP via qualitative evaluation. Color scheme: U, blue; V, purple; O, red; P, lavender; H, white.



population were derived using the ground-state electron density for UVP (Figure 4a, right). The LDA+U results determined that the net spin populations on uranium and vanadium are about 2.07 and 1.91, respectively, indicating that about four electrons of uranium and about three electrons of vanadium are ionized or participate with covalent bonds with the phosphite ligands. The net spin population analysis can be used as a direct evidence to confirm the 4+ and 3+ formal oxidation states of uranium and vanadium in the UVP crystal, respectively, in agreement with the experimental data. From Figure 4a (right), the section shapes of the net spin density on metals indicate that the net spins on uranium and vanadium are mainly f and d electrons, respectively. Further molecular orbital analyses show that the local electronic structures of uranium and vanadium can be characterized as 5f2 and 3d2, respectively, as shown in Figure 4b. To qualitatively evaluate the stability of UVP, we investigated the thermodynamic process for two hypothetical reactions involving oxidation in UVP (Figure 4c). In the first case, uranium(IV) was selected to be oxidized to uranium(VI) by oxygen and the net Gibbs free energy change (ΔG) was calculated to be −2.39 eV. In the second case, one phosphite ligand was specifically chosen to become oxidized; the resulting net ΔG was −4.90 eV in this process. It stands that the more favorable thermodynamic process is the second case, in which phosphite protects uranium(IV) and vanadium(III) from being oxidized, instead of sacrificing to become phosphate, consistent with XPS analysis. The use of phosphite as a means to protect

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Tao Zheng: 0000-0002-9381-8746 Ruhong Zhou: 0000-0001-8624-5591 Shuao Wang: 0000-0002-1526-1102 Author Contributions ‡

These authors contributed equally.

Notes

The authors declare no competing financial interest.



ACKNOWLEDGMENTS We thank the National Natural Science Foundation of China (Grants 21422704, 21471107, 21790370, 21790374, and 21761132019), the Science Challenge Project (JCKY2016212A504), the “Young Thousand Talented Program”, the General Financial Grant from the China Postdoctoral Science Foundation (Grant 2016M591901), and a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions for financial support of this work.



REFERENCES

(1) (a) Kozimor, S. A.; Bartlett, B. M.; Rinehart, J. D.; Long, J. R. Magnetic Exchange Coupling in Chloride-Bridged 5f−3d Hetero-

C

DOI: 10.1021/acs.inorgchem.7b02623 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry metallic Complexes Generated via Insertion into a Uranium(IV) Dimethylpyrazolate Dimer. J. Am. Chem. Soc. 2007, 129, 10672− 10674. (b) Kindra, D. R.; Evans, W. J. Magnetic susceptibility of uranium complexes. Chem. Rev. 2014, 114, 8865−8882. (c) Mandal, S.; Chandra, M.; Natarajan, S. Synthesis, Structure, and Upconversion Studies on Organically Templated Uranium Phosphites. Inorg. Chem. 2007, 46, 7935−7943. (d) Wang, Y.; Liu, Z.; Li, Y.; Bai, Z.; Liu, W.; Wang, Y.; Xu, X.; Xiao, C.; Sheng, D.; Diwu, J.; Su, J.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. Umbellate distortions of the uranyl coordination environment result in a stable and porous polycatenated framework that can effectively remove cesium from aqueous solutions. J. Am. Chem. Soc. 2015, 137, 6144−6147. (2) (a) Yeon, J.; Smith, M. D.; Tapp, J.; Möller, A.; zur Loye, H. C. Application of a mild hydrothermal approach containing an in situ reduction step to the growth of single crystals of the quaternary U(IV)containing fluorides Na4MU6F30 (M = Mn2+, Co2+, Ni2+, Cu2+, and Zn2+) crystal growth, structures, and magnetic properties. J. Am. Chem. Soc. 2014, 136, 3955−3963. (b) Yeon, J.; Smith, M. D.; Sefat, A. S.; zur Loye, H. C. Crystal growth, structural characterization, and magnetic properties of new uranium(IV) containing mixed metal oxalates: Na2U2M(C2O4)6(H2O)4 (M = Mn2+, Fe2+, Co2+, and Zn2+). Inorg. Chem. 2013, 52, 2199−2207. (c) Yeon, J.; Smith, M. D.; Morrison, G.; zur Loye, H. C. Trivalent cation-controlled phase space of new U(IV) fluorides, Na3MU6F30 (M = Al(3+), Ga(3+), Ti(3+), V(3+), Cr(3+), Fe(3+)): mild hydrothermal synthesis including an in situ reduction step, structures, optical, and magnetic properties. Inorg. Chem. 2015, 54, 2058−2066. (3) (a) Morrison, G.; Ramanantoanina, H.; Urland, W.; Smith, M. D.; zur Loye, H. C. Flux Synthesis, Structure, Properties, and Theoretical Magnetic Study of Uranium(IV)-Containing A2USi6O15 (A = K, Rb) with an Intriguing Green-to-Purple, Crystal-to-Crystal Structural Transition in the K Analogue. Inorg. Chem. 2015, 54, 5504−5511. (b) Lee, C.-S.; Lin, C.-H.; Wang, S.-L.; Lii, K.-H. [Na7UIVO2(UVO)2(UV/VIO2)2Si4O16]: A Mixed-Valence Uranium Silicate. Angew. Chem., Int. Ed. 2010, 49, 4254−4256. (c) Liu, H. K.; Lii, K. H. Cs2USi6O15: a tetravalent uranium silicate. Inorg. Chem. 2011, 50, 5870−5872. (d) Read, C. M.; Smith, M. D.; Withers, R.; zur Loye, H. C. Flux Crystal Growth and Optical Properties of Two UraniumContaining Silicates: A2USiO6 (A = Cs, Rb). Inorg. Chem. 2015, 54, 4520−4525. (4) (a) Lai, Y.-L.; Chiang, R.-K.; Lii, K.-H.; Wang, S.-L. The First Organically Templated Tetravalent Uranium Phosphates with DimerStructured Topologies. Chem. Mater. 2008, 20, 523−530. (b) Falaise, C.; Delille, J.; Volkringer, C.; Loiseau, T. Solvothermal Synthesis of Tetravalent Uranium with Isophthalate or Pyromellitate Ligands. Eur. J. Inorg. Chem. 2015, 2015, 2813−2821. (c) Wang, C. M.; Wu, Y. Y.; Chen, P. L.; Lii, K. H. Organically templated uranium(IV) fluorooxalates with layer structures: (H4TREN)[U2F6(C2O4)3].4H2O (TREN = tris(2aminoethyl)amine) and (H4APPIP)[U2F6(C2O4)3].4H2O (APPIP = 1,4-bis(3-amino-propyl)piperazine. Dalton Trans. 2007, 1034−1037. (5) (a) Roth, O.; Jonsson, M. Oxidation of UO2(s) in aqueous solution. Open Chemistry 2008, 6, 1−14. (b) Appel, L.; Leduc, J.; Webster, C. L.; Ziller, J. W.; Evans, W. J.; Mathur, S. Synthesis of air-stable, volatile uranium(IV) and (VI) compounds and their gas-phase conversion to uranium oxide films. Angew. Chem., Int. Ed. 2015, 54, 2209−2213. (6) (a) Brandel, V.; Dacheux, N.; Genet, M. Studies on the Chemistry of Uranium and Thorium Phosphates. Thorium Phosphate Diphosphate: A Matrix for Storage of Radioactive Wastes. Radiochemistry 2001, 43, 16−23. (b) Gui, D.; Zheng, T.; Chen, L.; Wang, Y.; Li, Y.; Sheng, D.; Diwu, J.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. Hydrolytically Stable Nanoporous Thorium Mixed Phosphite and Pyrophosphate Framework Generated from Redox-Active Ionothermal Reactions. Inorg. Chem. 2016, 55, 3721−3723. (c) Liu, C.; Yang, W.; Qu, N.; Li, L. J.; Pan, Q. J.; Sun, Z. M. Construction of Uranyl Organic Hybrids by Phosphonate and in Situ Generated Carboxyphosphonate Ligands. Inorg. Chem. 2017, 56, 1669−1678. (7) (a) Villa, E. M.; Marr, C. J.; Jouffret, L. J.; Alekseev, E. V.; Depmeier, W.; Albrecht-Schmitt, T. E. Systematic Evolution from Uranyl(VI) Phosphites to Uranium(IV) Phosphates. Inorg. Chem. 2012, 51, 6548−

6558. (b) Villa, E. M.; Marr, C. J.; Diwu, J.; Alekseev, E. V.; Depmeier, W.; Albrecht-Schmitt, T. E. From Order to Disorder and Back Again: In Situ Hydrothermal Redox Reactions of Uranium Phosphites and Phosphates. Inorg. Chem. 2013, 52, 965−973. (c) Gui, D.; Zheng, T.; Xie, J.; Cai, Y.; Wang, Y.; Chen, L.; Diwu, J.; Chai, Z.; Wang, S. Significantly Dense Two-Dimensional Hydrogen-Bond Network in a Layered Zirconium Phosphate Leading to High Proton Conductivities in Both Water-Assisted Low-Temperature and Anhydrous IntermediateTemperature Regions. Inorg. Chem. 2016, 55, 12508−12511. (d) Zheng, T.; Wu, Q. Y.; Gao, Y.; Gui, D.; Qiu, S.; Chen, L.; Sheng, D.; Diwu, J.; Shi, W. Q.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. Probing the influence of phosphonate bonding modes to uranium(VI) on structural topology and stability: a complementary experimental and computational investigation. Inorg. Chem. 2015, 54, 3864−3874. (8) (a) Jouffret, L.; Rivenet, M.; Abraham, F. Linear alkyl diamineuranium-phosphate systems: U(VI) to U(IV) reduction with ethylenediamine. Inorg. Chem. 2011, 50, 4619−4626. (b) Diwu, J.; Wang, S.; Albrecht-Schmitt, T. E. Periodic trends in hexanuclear actinide clusters. Inorg. Chem. 2012, 51, 4088−4093. (c) Diwu, J.; Albrecht-Schmitt, T. E. Mixed-valent uranium(IV,VI) diphosphonate: synthesis, structure, and spectroscopy. Inorg. Chem. 2012, 51, 4432−4434. (d) Chen, L.; Zheng, T.; Bao, S.; Zhang, L.; Liu, H. K.; Zheng, L.; Wang, J.; Wang, Y.; Diwu, J.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. A Mixed-Valent Uranium Phosphonate Framework Containing U(IV), U(V), and U(VI). Chem. Eur. J. 2016, 22, 11954−11957. (e) Chen, L.; Diwu, J.; Gui, D.; Wang, Y.; Weng, Z.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. Systematic Investigation of the in Situ Reduction Process from U(VI) to U(IV) in a Phosphonate System under Mild Solvothermal Conditions. Inorg. Chem. 2017, 56, 6952−6964. (9) (a) Rojo, T.; Mesa, J. L.; Lago, J.; Bazan, B.; Pizarro, J. L.; Arriortua, M. I. Organically templated open-framework phosphites. J. Mater. Chem. 2009, 19, 3793. (b) Shvareva, T. Y.; Skanthakumar, S.; Soderholm, L.; Clearfield, A.; Albrecht-Schmitt, T. E. Cs+-selective ion exchange and magnetic ordering in a three-dimensional framework uranyl vanadium (IV) phosphate. Chem. Mater. 2007, 19, 132−134. (c) Shvareva, T. Y.; Beitz, J. V.; Duin, E. C.; Albrecht-Schmitt, T. E. Polar Open-Framework Structure, Optical Properties, and Electron Paramagnetic Resonance of the Mixed-Metal Uranyl Phosphate Cs2 [UO2(VO2)2(PO4)2]⊙0.59H2O. Chem. Mater. 2005, 17, 6219−6222. (10) (a) Wang, Y.; Yin, X.; Zhao, Y.; Gao, Y.; Chen, L.; Liu, Z.; Sheng, D.; Diwu, J.; Chai, Z.; Albrecht-Schmitt, T. E.; Wang, S. Insertion of Trivalent Lanthanides into Uranyl Vanadate Layers and Frameworks. Inorg. Chem. 2015, 54, 8449−8455. (b) Senchyk, G. A.; Wylie, E. M.; Prizio, S.; Szymanowski, J. E.; Sigmon, G. E.; Burns, P. C. Hybrid uranylvanadium nano-wheels. Chem. Commun. 2015, 51, 10134−10137. (11) Brese, N.; O’keeffe, M. Bond-valence parameters for solids. Acta Crystallogr., Sect. B: Struct. Sci. 1991, 47, 192. (12) Liu, J. H.; Van den Berghe, S.; Konstantinović, M. J. XPS spectra of the compounds, and. J. Solid State Chem. 2009, 182, 1105−1108. (13) Werfel, F.; Brümmer, O. Corundum Structure Oxides Studied by XPS. Phys. Scr. 1983, 28, 92. (14) Lin, X.; Dong, Y.; Kuang, Q.; Yan, D.; Liu, X.; Han, W.; Zhao, Y. Synthesis, structural, and electrochemical properties of NaCo(PO3)3 cathode for sodium-ion batteries. J. Solid State Electrochem. 2016, 20, 1241−1250. (15) (a) Bao, S.-S.; Zheng, L.-M. Magnetic materials based on 3d metal phosphonates. Coord. Chem. Rev. 2016, 319, 63−85. (b) Zeng, D.; Ren, M.; Bao, S. S.; Cai, Z. S.; Xu, C.; Zheng, L. M. Polymorphic Lanthanide Phosphonates Showing Distinct Magnetic Behavior. Inorg. Chem. 2016, 55, 5297−5304. (c) Feng, J.-S.; Ren, M.; Cai, Z.-S.; Fan, K.; Bao, S.-S.; Zheng, L.-M. Enantiopure phosphonic acids as chiral inducers: homochiral crystallization of cobalt coordination polymers showing field-induced slow magnetization relaxation. Chem. Commun. 2016, 52, 6877−6880. (16) (a) Aldous, D. W.; Stephens, N. F.; Lightfoot, P. Hydrothermal Vanadium Fluoride Chemistry: Four New V3+ Chain Structures. Inorg. Chem. 2007, 46, 3996−4001. (b) Shaw, R.; et al. 1,2,3-TriazolateBridged Tetradecametallic Transition Metal Clusters [M14(L)6O6(OMe)18X6] (M = FeIII, CrIII and VIII/IV) and Related D

DOI: 10.1021/acs.inorgchem.7b02623 Inorg. Chem. XXXX, XXX, XXX−XXX

Communication

Inorganic Chemistry Compounds: Ground-State Spins Ranging from S = 0 to S = 25 and SpinEnhanced Magnetocaloric Effect. Inorg. Chem. 2007, 46, 4968−4978. (c) Hamchaoui, F.; Alonzo, V.; Venegas-Yazigi, D.; Rebbah, H.; Le Fur, E. Six novel transition-metal phosphite compounds, with structure related to yavapaiite: Crystal structures and magnetic and thermal properties of AI[MIII(HPO3)2] (A = K, NH4, Rb and M = V, Fe). J. Solid State Chem. 2013, 198, 295−302. (17) Huang, H. L.; Wang, S. L. An extraordinary boron-mediated 16Rchannel-containing trivalent vanadium phosphite with unique solid state redox properties. Chem. Commun. 2010, 46, 6141−6143. (18) Majjane, A.; Chahine, A.; Et-tabirou, M.; Echchahed, B.; Do, T.O.; Breen, P. M. X-ray photoelectron spectroscopy (XPS) and FTIR studies of vanadium barium phosphate glasses. Mater. Chem. Phys. 2014, 143, 779−787.

E

DOI: 10.1021/acs.inorgchem.7b02623 Inorg. Chem. XXXX, XXX, XXX−XXX