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Purple crystals of ethylenediammonium cobalt bis(hydrogen phosphite) dichloride were produced from an aqueous solution containing ethylenediamine, cobalt chloride, and phosphorous acid. The new compound is monoclinic, P21/c, a = 8.6665(3) Å, b = 7.2866(2) Å, c = 9.7300(3) Å, β = 112.726(3); V = 566.74(3) Å3, Z = 2. The 2D structure comprised ethylenediammonium cations sandwiched between the [Co(HPHO3)2Cl2]2− layers. The latter are built of trans-CoO4Cl2 octahedra linked by hydrogen-bonded dimers of hydrophosphite ions, (HPHO3)22−. The new compound is a complete structural analog of the recently reported (C2N2H10)[Co(HSeO3)2Cl2] and isostructural analogs with other transition metal dications; it is, in fact, the first representative of a new "layered hydrophosphite" family. Its structure provides yet another illustration of essential similarities in the crystal chemistry of selenites and phosphites, including protonated species, wherein the lone pair of SeIV and the nearly nonpolar P–H enhance formation of loose and/or open-framework structural architectures. [ABSTRACT FROM AUTHOR]

Single crystals of two new intermetallic phases Sm2Mn1−xGa6−yGey (x = 0.1–0.3, y = 0.6–1.0) and Sm4MnGa12−yGey (y = 3.0–3.5) were grown using a self-flux technique. According to single crystal X-ray diffraction data, Sm4MnGa12−yGey is characterised by the Y4PdGa12 structure type (a ∼ 8.65 Å; Im3¯m), while Sm2Mn1−xGa6−yGey formally adopts the K2PtCl6 structure type (a ∼ 8.71 Å; Fm3¯m). The general features of both compounds with rather similar crystal structures are represented by the alternation of empty and Mn-filled p-element octahedra, the order of which is determined by the Mn concentration. The diffraction data for Sm2Mn1−xGa6−yGey reveal a large concentration of Mn vacancies (x ∼ 0.3), which affects adjacent Ga/Ge atoms leading to their shift towards the vacancy. Both compounds demonstrate two ferromagnetic-like transitions and the presence of two interacting Mn and Sm magnetic sublattices. The Mn sublattice orders at TC1 of 143 K and 318 K, while the Sm one orders at lower temperatures at TC2 of 50 K and 280 K for Sm4MnGa8.6Ge3.4 and Sm2Mn0.74Ga5.1Ge0.9, respectively. The increase in Mn content not only increases the ordering temperatures, but also dramatically decreases the coercivity μ0HC from 230 mT to just 6.5 mT at 2 K. Despite the presence of two magnetically active sublattices in Sm2Mn0.74Ga5.1Ge0.9, the magnetic entropy change is quite low and only reaches 0.3 J kg−1 K−1 at T = 300 K and μ0H = 5 T, while the estimated relative cooling power (RCP) is about 36 J kg−1 at 5 T. [ABSTRACT FROM AUTHOR]

A new series of Sr-based phosphates, Sr9−xMnxEu(PO4)7, were synthesized using the high-temperature solid-state method in air. It was found that these compounds have the same structure as strontiowhitlockite, which is a β-Ca3(PO4)2 (or β-TCP) structure. The concentration of Mn2+ ions required to form a pure strontiowhitlockite phase was determined. An unusual partial reduction of Eu3+ to Eu2+ in air was observed and confirmed by photoluminescence (PL) and electron spin resonance (ESR) spectra measurements. The PL spectra recorded under 370 nm excitation showed transitions of both 4f5d–4f Eu2+ and 4f–4f Eu3+. The total integral intensity of the PL spectra, monitored at 395 nm, decreased with increasing Mn2+ concentration due to quenching effect of Eu3+ by the Mn2+ levels. The temperature dependence of Eu2+ photoluminescence in a Sr9−xMnxEu(PO4)7 host was investigated. The conditions for the reduction of Eu3+ to Eu2+ in air were discussed. [ABSTRACT FROM AUTHOR]

β-Tricalcium phosphate (β-TCP) is widely used as bone implant material. It has been observed that doping the β-TCP structure with certain cations can help in combating bacteria and pathogenic microorganisms. Previous literature investigations have focused on tricalcium phosphate structures with silver, copper, zinc, and iron cations. However, there are limited studies available on the biological properties of β-TCP containing nickel and cobalt ions. In this work, Ca10.5−xNix(PO4)7 and Ca10.5−xCox(PO4)7 solid solutions with the β-Ca3(PO4)2 structure were synthesized by a high-temperature solid-state reaction. Structural studies revealed the β-TCP structure becomes saturated at 9.5 mol/% for Co2+ or Ni2+ ions. Beyond this saturation point, Ni2+ and Co2+ ions form impurity phases after complete occupying of the octahedral M5 site. The incorporation of these ions into the β-TCP crystal structure delays the phase transition to the α-TCP phase and stabilizes the structure as the temperature increases. Biocompatibility tests conducted on adipose tissue-derived mesenchymal stem cells (aMSC) using the (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) (MTT) assay showed that all prepared samples did not exhibit cytotoxic effects. Furthermore, there was no inhibition of cell differentiation into the osteogenic lineage. Antibacterial properties were studied on the C. albicans fungus and on E. coli, E. faecalis, S. aureus, and P. aeruginosa bacteria strains. The Ni- and Co-doped β-TCP series exhibited varying degrees of bacterial growth inhibition depending on the doping ion concentration and the specific bacteria strain or fungus. The combination of antibacterial activity and cell-friendly properties makes these phosphates promising candidates for anti-infection bone substitute materials. [ABSTRACT FROM AUTHOR]

Aminoguanidinium thiosulfate, (CN4H7)2S2O3 (1), was prepared via an exchange route from barium thiosulfate and aminoguanidinium sulfate. The new compound is monoclinic, a=12.8344(6) Å, b=13.9134(6) Å, c=6.8757(3) Å, β=115.529(5)°, and crystallizes in a centrosymmetric C2/m space group. Its crystal structure can be considered either as pseudo‐columnar comprised of stacked [CN4H7]+ cations and isolated [S2O3]2− anions which are actively involved in hydrogen bonding, or as H‐bonded bilayers comprised of both [CN4H7]+ and [S2O3]2− of topologic type 3,6L60. The latter ones are H‐bound into a 4,8‐coordinated bearing framework of the type scu. [ABSTRACT FROM AUTHOR]