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A set of different open framework iron phosphates have been synthesized ionothermally using a task-specific ionic liquid, 1-butyl-4-methylpyridinium hexafluorophosphate, that acts in the synthesis as the reaction medium and mineralizer: (NH4)2Fe2(HPO4)(PO4)Cl2F (1) and K2Fe2(HPO4)(PO4)Cl2F (2) exhibit similar composition and closely related structural features. Both structures consist of {Fe2(HPO4)(PO4)Cl2F}2–macroanions and charge balancing ammonium or potassium cations. Their open framework structure contains layers and chains of corner-linked {Fe(1)O2Cl4} and {Fe(2)F2O4} octahedra, respectively, interconnected by PO4tetrahedra forming 10-ring channels. KFe(PO3F)F2(3) is built up by {Fe[(PO3F)4/3F2/2]}{Fe(PO3F)2/3F2/2F2} layers separated by K+cations. Chains of alternating {FeF2O4} and {FeO2F4} octahedra, which are linear for 1but undulated for 2, are linked to each other via corner-sharing {PO3F} tetrahedra with the fluorine pointing into the interlayer space. The compounds were characterized by means of single crystal and powder X-ray diffraction, infrared spectroscopy, and magnetic measurements. 1reveals a strong ground state spin anisotropy with a spin 5/2 state and a magnetic moment of 5.3 μB/Fe3+. Specific heat and magnetic data unveil three magnetic transitions at 95, 50, and 3.6 K. Compound 2has a very similar crystal structure as compared to 1but exhibits a different magnetic behavior: a slightly lower magnetic moment of 4.7 μB/Fe3+and a magnetic transition to a canted antiferromagnetic state below 90 K. Compound 3exhibits typical paramagnetic behavior close to room-temperature (5.71 μB/Fe3+). There are no clear indications for a phase transition down to 2 K despite strong antiferromagnetic spin–spin interactions; only a magnetic anomaly appears at 50 K in the zero-field cooled data.

An ionothermal synthesis study of transition metal phosphates using the ionic liquid 1-butyl-4-methylpyridinium hexafluorophosphate [C4mpy][PF6] yielded four new, different open framework manganese compounds, that is, K2Mn3(HPO4)2(PO3F)F2(1), (NH4)2Mn3(HPO4)2(PO3F)F2(2), KMn3(H2PO4)(HPO4)2F2(3), and (NH4)Mn3(H2PO4)(PO3F)2F2(4). The obtained products not only feature new framework topologies unprecedented in the family of phosphates but also interesting properties as the transition metal gives rise to both luminescent (rendering them potential nonrare earth containing red emitting phosphors) and unconventional magnetic properties governed by geometric frustrations. Aside from the structural analysis (powder and single-crystal X-ray diffraction, infrared spectroscopy), a variety of characterization methods (photoluminescence spectroscopy and magnetic measurements) were applied to study the material’s properties. Single crystal X-ray studies reveal that 1(P21/cwith a= 5.501(1), b= 14.203(3), c= 16.905(4) Å, β = 108.65(3)°, V= 1251.4 Å3, and Z= 4) and 2(P21/cwith a= 5.587(1), b= 14.507(3), c= 17.364(3) Å, β = 108.75(3)°, V= 1332.6(5) Å3, and Z= 4) feature S-shaped 18-ring channels along [100], which are formed by trimer-Mn3O9F2chains parallel to [100] and interconnecting PO3(OH) and PO3F tetrahedra. The structure of compounds 3(C2/cwith a= 20.307(4), b= 7.635(1), c= 7.834(2) Å, β = 103.26(3)°, V= 1182.2(4) Å3, and Z= 4) and 4(C2/cwith a= 20.402(4), b= 7.673(1), c= 7.845(2) Å, β = 103.56(3)°, V= 1193.8(4) Å3, and Z= 4) are characterized by layers, which are built of Mn3O8F4octahedra trimers, with Kagomé topology parallel to the bcplane featuring 3,6-ring channels. The layers are stacked according to a sequence of AAialong the aaxis. Taking into account the [P(2)O3(OH)/P(2)O3F] tetrahedra, the Kagomé layers are replenished to a Mn3O2(HPO4)/Mn3O2(PO3F) composition, which are interlinked by [P(1)O2(OH)2] forming 10-ring channels parallel to [001]. Charge compensation of the macroanions is achieved by K+(1and 3) and (NH4)+(2and 4) cations. At room temperature, compounds 1–4demonstrate a reddish orange emission ascribed to the spin-forbidden 4T1g(4G) → 6A1g(6S) transition of the Mn2+ions. Upon lowering the temperature to 77 K, the emission of each compound is red-shifted and becomes pure red. Compounds 1and 2contain spin trimers with a presumable doubled ground state. The intertrimer magnetic coupling is relatively weak, and small ferrimagnetic domains are possible in 1. The magnetic behavior of 3and 4can be considered as antiferromagnetic. This can be understood as their staircase Kagomé lattices are distorted, meaning that the intrinsic geometrical frustration is lifted.

Risk models integrating new biomarkers to predict cardiovascular events in acute coronary syndromes (ACS) are lacking. Therefore, we evaluated the prognostic value of biomarkers in addition to clinical predictors and developed a biomarker-based risk model for major adverse cardiovascular events (MACE) within 12 months after hospital admission with ACS.

A new open‐framework manganese borophosphate, KMnBP2O7(OH)2, has been prepared under ionothermal conditions in the ionic liquid 1‐butyl‐1‐methylpyrrolidinium bromide. Single‐crystal X‐ray diffraction analysis showed that KMnBP2O7(OH)2[monoclinic, P21/c, a= 6.659(1), b= 12.049(2), c= 9.790(2) Å, β= 109.12(3)°, V= 742.2(3) Å3, and Z= 4] has an unprecedented open‐framework structure. {MnO5(OH)} octahedra and {BO3(OH)} and {PO3(OH)}/{PO4} tetrahedra link to form a 3D framework with distorted eight‐membered‐ring channels along the crystallographic [001] direction. The negative charges of the inorganic framework are balanced by K+ions located in the channels. At room temperature, KMnBP2O7(OH)2shows a bright orange‐red luminescence that redshifts with decreasing temperature. The luminescence lifetimes were determined to be 0.17 ms at room temperature and 3.49 ms at 77 K. Below 3 K, d5Mn2+of two neighboring, edge‐sharing {MnO5OH}2units couple antiferromagnetically, and the magnetic state can be best described as a singlet spin system. These singlets continuously turn into triplets when increasing the magnetic field up to 7 T at 2 K due to relatively weak spin–spin coupling through two identical 98.92(6)° Mn–O–Mn superexchange paths, turning the system into a metastable ferromagnetic state.

This paper describes the synthesis and characterization of γ-zirconium phosphate-phosphonates based on chiral N-phosphonomethyl-L-proline [(−)-HO3PCH2NHC4H7CO2H; H3PMP] from L-proline, and N-phosphonomethyl-1,3-thiazolidine-4-carboxylic acid [(−)-HO3PCH2NHCH2SC2H3CO2H; H3PMTA] from L-cysteine. Two compounds formulated as [Zr(PO4)(H2PO4)0.53(H2PMP)0.47·2.0H2O] [γ-ZrPMP (1)] and [Zr(PO4)(H2PO4)0.50(H2PMT)0.50·1.6H2O] [γ-ZrPMT (2)] were obtained by topotactic reaction of H3PMP and H3PMTA, respectively, with γ-ZrP in the presence of water/acetone. They possess intercalation capabilities and optical activities. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.