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Abstract: A new molybdenum containing oxyfluoride, BaMoOF5, space group Cmcm with lattice parameters of a = 7.1445(3), b = 6.7894(3), c = 10.1969(4), was synthesized via a mild hydrothermal crystal growth method. The synthesis resulted in high-quality single crystals of the title material, which were characterized by single-crystal X-ray diffraction. The structure is discussed in detail.Graphical Abstract: A new Mo(V) oxyfluoride, BaMoOF5, was synthesized via a mild hydrothermal route that included an in-situ reduction step to reduce molybdenum from a starting oxidation state of 6+ to 5+. [ABSTRACT FROM AUTHOR]

Abstract: A new molybdenum containing oxyfluoride, BaMoOF5, space group Cmcm with lattice parameters of a = 7.1445(3), b = 6.7894(3), c = 10.1969(4), was synthesized via a mild hydrothermal crystal growth method. The synthesis resulted in high-quality single crystals of the title material, which were characterized by single-crystal X-ray diffraction. The structure is discussed in detail.Graphical Abstract: A new Mo(V) oxyfluoride, BaMoOF5, was synthesized via a mild hydrothermal route that included an in-situ reduction step to reduce molybdenum from a starting oxidation state of 6+ to 5+. [ABSTRACT FROM AUTHOR]

A cobalt containing mixed-anion uranyl oxide-fluoride was synthesized using a mild hydrothermal crystal growth method. The uranyl ions are condensed into a one-dimensional chain motif separated by isolated cobalt hexa-aqua centers. The 1-D uranyl material was characterized by single-crystal and powder X-ray diffraction. The optical, thermal, and magnetic properties were studied and are reported herein. Using the reported composition as a model, a system was derived to predict the dimensionality of hypothetical structures to advance our ability to rationally predict solid-state materials. [ABSTRACT FROM AUTHOR]

High quality single crystals of the monoclinic phase K5U5O17(OH) were synthesized via a hydrothermal method utilizing the supercritical regime of water. The structure of K5U5O17(OH) is isotypic with the Na phase, Na5U5O17(OH), however crystallizes in a slightly different space group due to size effects. K5U5O17(OH) has the same sheet-anion structure as the Na analog, whose topology is analyzed here for the first time. K5U5O17(OH) shows fluorescence typical for uranyl species. [ABSTRACT FROM AUTHOR]

Four new vanadium oxyfluorides (VOFs), Sr4V3O5F13 (1), Pb7V4O8F18 (2), Pb2VO2F5 (3), and Pb2VOF6 (4), have been synthesized under mild hydrothermal conditions. The choice of starting reagents, AF2 or A(CH3CO2)2·xH2O (A = Pb, alkaline earth), determined the oxidation states of vanadium in the final products. The reaction of V2O5 with AF2 leads, consistently, to the formation of V(v) compounds, while the use of A(CH3CO2)2·xH2O results in V(iv) containing compounds, suggesting that the acetate species behaves as an effective mild reducing agent. The crystal structures, characterized by single crystal X-ray diffraction, revealed that the compounds exhibit various anionic VOF building blocks, including dimeric and trinuclear units, as well as one-dimensional chains. All compounds contain fluorine atoms that are not bonded to the vanadium atoms, which are located between two-dimensional layers consisting of corner- or edge-shared FA3 or FA4 polyhedra that separate the vanadium containing building blocks. The magnetic susceptibility data for 4 were measured as a function of temperature, yielding an effective magnetic moment of 1.72 μB that confirms the presence of V(iv). UV-vis reflectance and thermal properties were also characterized. [ABSTRACT FROM AUTHOR]

Crystals of the anti-Perovskites (III), (V), (VIII), (IX), and (X) are hydrothermally prepared with yields greater than 90% and characterized by single crystal XRD, UV/VIS spectroscopy, and magnetic measurements. [ABSTRACT FROM AUTHOR]

Single crystals of K2TiOF4 are grown hydrothermally from mixtures of TiF3, KF, HF, and H2O (autoclave, 200 °C, 24 h, 75% yield). The compound crystallizes isostructurally with K2VOF4 in the orthorhombic space group Pnma with Z = 4 (single crystal XRD). The crystal structures of anhydrous K2TiOF4 and K2TiOF4⋅H2O are compared. [ABSTRACT FROM AUTHOR]

Materials discovery and optimization has driven the rapid technological advancements that have been observed in our lifetimes. For this advancement to continue, solid-state chemists must continue to develop new materials. Where do these new materials come from? In this review, we discuss the approaches used by the zur Loye group to discover the next "First Material", a new material exhibiting a desired or not previously observed property that can be optimized for use in the technologies of tomorrow. Specifically, we discuss several crystal growth techniques that we have used with great success to synthesize new materials: the flux growth method, the hydroflux method, and the mild-hydrothermal method. [ABSTRACT FROM AUTHOR]

Geometrically frustrated systems play an important role in studying new physical phenomena and unconventional thermodynamics. Charge ordered defect pyrochlores AM 2+ M 3+ F 6 offer a convenient platform for probing the interplay between electron distribution over M 2+ and M 3+ sites and structural distortions; however, they are limited to compounds with M 2+/3+ = V, Fe, Ni, and Cu due to difficulties in the simultaneous stabilization of other 3d elements in the +2 and +3 oxidation states. Herein, we employ Cl - anions under hydrothermal conditions for the mild reduction of Mn 2 O 3 in concentrated HF to obtain the CsMn 2+ Mn 3+ F 6 composition as a phase pure sample and study its properties. The magnetism of CsMn 2 F 6 was characterized by measuring the magnetic susceptibility and isothermal magnetization data, and a magnetic transition to a canted antiferromagnet state was found at 24.1 K. We determined the magnetic structure of CsMn 2 F 6 using powder neutron diffraction, which revealed successive long-range ordering of the Mn 2+ and Mn 3+ sites that is accompanied by a second transition. The role and strength of magnetic exchange interactions were characterized using DFT calculations.

A new uranium fluoride phosphate, UFPO 4 , was synthesized via a mild hydrothermal route and characterized optically, thermally, and magnetically. Two thermal transformation products, U 2 O(PO 4 ) 2 and U IV U VI O 2 (PO 4 ) 2 , were discovered to be structurally related, and were subsequently synthesized for bulk property measurements. All three materials failed to follow Curie-Weiss behavior at low temperatures, attributed to the nearly ubiquitous singlet ground state of U(IV), transitioning into a Curie-Weiss paramagnetic regime at high temperatures. Neutron diffraction experiments were performed on UFPO 4 and U IV U VI O 2 (PO 4 ) 2 in order to characterize this unusual magnetic behavior.