A Submersible Phosphate Analyzer for Marine Environments based on Inlaid Microfluidics

In situ sensors are needed to further our understanding of phosphate flux dynamics in marine environments during short term events such as tidal cycles, algae blooms and runoff periods. Here,...

Thallium diphosphates

Three thallium(I) diphosphates with compositions Tl4P2O7, Tl2H2P2O7, Tl2H2P2O7(H2O)0.5 and the mixed-valent thallium(I,III) diphosphate Tl2P2O7 (= TlITlIIIP2O7) were obtained from aqueous solutions using an ion-exchange resin (Tl4P2O7), through thermal treatment of TlH2PO4 at 190 °C and subsequent crystallization from aqueous solutions (Tl2H2P2O7, Tl2H2P2O7(H2O)0.5), and from a phosphate flux at 220 °C (Tl2P2O7). The crystal structures of monoclinic Tl4P2O7 (C2/c, Z = 4) and orthorhombic Tl2H2P2O7 (Pbca, Z = 8) are unique, whereas monoclinic Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) is isotypic with its potassium analogue, and triclinic Tl2P2O7 (P$‾{1}$, Z = 4) crystallizes in the TlInAs2O7 structure type. The crystal structure of Tl2P2O7 is related to that of In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) by a translationengleiche group-subgroup relationship (t2). IR spectra of Tl4P2O7, Tl2H2P2O7 and Tl2P2O7 are reported and discussed.

Thallium diphosphates

Three thallium(I) diphosphates with compositions Tl4P2O7, Tl2H2P2O7, Tl2H2P2O7(H2O)0.5 and the mixed-valent thallium(I,III) diphosphate Tl2P2O7 (= TlITlIIIP2O7) were obtained from aqueous solutions using an ion-exchange resin (Tl4P2O7), through thermal treatment of TlH2PO4 at 190 °C and subsequent crystallization from aqueous solutions (Tl2H2P2O7, Tl2H2P2O7(H2O)0.5), and from a phosphate flux at 220 °C (Tl2P2O7). The crystal structures of monoclinic Tl4P2O7 (C2/c, Z = 4) and orthorhombic Tl2H2P2O7 (Pbca, Z = 8) are unique, whereas monoclinic Tl2H2P2O7(H2O)0.5 (C2/c, Z = 8) is isotypic with its potassium analogue, and triclinic Tl2P2O7 (P$‾{1}$, Z = 4) crystallizes in the TlInAs2O7 structure type. The crystal structure of Tl2P2O7 is related to that of In2P2O7 (= InIInIIIP2O7; P21/c, Z = 4) by a translationengleiche group-subgroup relationship (t2). IR spectra of Tl4P2O7, Tl2H2P2O7 and Tl2P2O7 are reported and discussed.

Two-dimensional zeolite-like network in the new caesium copper aluminate Cs2CuAl4O8

Monoclinic dicaesium copper tetraaluminate, Cs2CuAl4O8, space groupP21/c,a= 8.4551 (7),b= 10.012 (1),c= 17.073 (2) Å, β = 101.643 (9)°,Z= 6, was obtained by high-temperature crystallization from a phosphate flux. Its microporous crystal structure presents the first example of double layers built from [AlO4] tetrahedra combined in 4-, 6- and 8-rings, topologically similar to those found in theATT-type zeolites and isostructural minerals armstrongite, davanite and dalyite. These layers show a rare arrangement of three [AlO4] tetrahedra sharing one oxygen vertex. The aluminate slabs are further linked by chains of edge-sharing [CuO4] square planes to form a mixed anionic three-dimensional framework with Cs+cations in channels and cavities. An unusually short Cu...Cs distance of 3.166 Å is ascribed to the strong Jahn–Teller effect of Cu2+. The magnetic subsystem demonstrates properties of an alternating antiferromagnetic chain with a gap in the spectrum of magnetic excitations.