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A novel organic sulfate (C4H16N3)SO4⋅HSO4 has been prepared and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and differential scanning calorimetry (DSC). The structure consists of linked HSO4− and SO42− anions assembled into clusters. Organic triple-protonated diethylene triammonium cations are interconnected to these clusters via N–H−O hydrogen bonds to create the three dimensional arrangement. The Hirshfeld surface and associated fingerprint plots of the compound were presented to explore the nature of intermolecular interactions and their relative contributions to building the solid-state architecture. TG-DTA and DSC studies showed the presence of two phase transitions. Infrared spectrum is reported and discussed on the basis of group theoretical analysis and on Density Functional Theory calculations.

Gadolinium ultraphosphate, GdP5O14 has been synthesized by a flux method. The room temperature structure of the title compound was solved from twinned single-crystal X-ray diffraction data in the monoclinic space group P21/c with a = 8.7411(3); b = 8.8997(2); c = 12.9308(5) A; β = 90.07(2)°; V = 1005.93(6) A3 and Z = 4. Crystals of the title compound exhibit twinning by pseudomerohedry. The apparent symmetry is caused by twinning and by the pseudo-orthorhombic symmetry of the lattice. Due to the pseudosymmetry the space group Pnmb has been assigned and after a complete structure refinement applied to a twinned crystal, the correct space group is P21/c. The atomic arrangement in the present structure is very close to the previously reported one of GdP5O14 at T = 145 K (type I) [J.M. Cole, M.R. Lees, J.A.K. Howard, R.J. Newport, G.A. Saunders, E. Schonherr, J. Solid State Chem. 150 (2000) 377], but a small deviation in the unit cell has been notified. The refinement gave R1 = 2.1% and w R 2 = 8.4 % based on 4138 independent reflections and 3619 observed, I > 2σ(I). The result of structural analysis establishes that the structure is built up with discrete anionic ribbons linked by the cations in a complex way. Magnetic susceptibility studies show paramagnetic behavior, following Curie's law with a magnetic moment of 7.96μB per formula unit.

Crystals of a new silver-gadolinium, AgGd(PO 3 ) 4 , have been synthesized for the first time by a flux method. The structure [monoclinic, P 2 1 / n , a = 7.2378(2) A, b = 13.0913(5) A, c = 9.8136(4) A, β = 90.494(1)°, V = 929.83(6) A 3 and Z = 4] was solved by a three-dimensional Patterson function and refined to R 1 = 0.0399 ( w R 2 = 0.0885 ) on the basis of 3270 unique observed reflexions using 164 parameters. AgGd(PO 3 ) 4 is isostructural to NaLa(PO 3 ) 4 , AgLa(PO 3 ) 4 and AgNd(PO 3 ) 4 . The structure is based upon long chain polyphosphate running along the shortest unit-cell direction and made up of PO 4 tetrahedra (with a period of four tetrahedra) sharing two corners, linked to the polyhedra of gadolinium and silver by common oxygen atoms to the chains. This type of organisation gives rise to a three-dimensional framework. Gadolinium atoms have an eight-fold coordination while silver atoms have approximately six oxygen neighbours. Infrared spectrum of AgGd(PO 3 ) 4 at room temperature, investigated in the frequency range 400–1500 cm −1 , confirms the atomic arrangement within the structure. The electrical conductivity of AgGd(PO 3 ) 4 has been measured on pellets of the polycrystalline powder and evaluated as a function of temperature. The conductivity of this phase was quite low and the values of 4.01 × 10 −7 and 1.10 × 10 −6 Ω −1 cm −1 were obtained at 803 and 873 K, respectively.

The crystal structure of gadolinium metaphosphate Gd(PO{sub 3}){sub 3} has been established by X-ray diffraction. This compound crystallizes in the orthorhombic system (space group C222{sub 1}, Z=4) with cell parameters: a=8.4530 (3), b=11.0576 (4) and c=7.1952 (2)A. The structure was refined to R{sub 1}=0.0234 and wR{sub 2}=0.0502 using 2180 independent reflections (I>2{sigma}(I)). Phosphorus atoms are in slightly irregular tetrahedral oxygen coordination, gadolinium atoms are in considerably distorted dodecahedral oxygen coordination. Formally, the 3D framework in the structure can be described by the PO{sub 4} tetrahedra sharing corners to form helical chains and the GdO{sub 8} polyhedra sharing edges in a zigzag fashion. The shortest Gd-Gd distance is 4.174 (2)A. The infrared spectrum of the title compound recorded at room temperature in the frequency range of 400-4000cm{sup -1}, confirm the atomic arrangement within the structure. Below T{sub C}=25K, the magnetic susceptibility evolution is characteristic of a ferromagnetic order. In the high-temperature region above 100K, the susceptibility follows a Curie-Weiss law with C=7.91cm{sup 3}Kmol{sup -1} and {theta}=9.96K.

Crystal structure and ionic conductivity of lithium gadolinium polyphosphate, LiGd(PO3)4, were investigated. Single crystals of the title compound have been grown by a flux technique. The structure of this novel phosphate was determined by single crystal X-ray diffraction techniques. LiGd(PO3)4 is isotypic with LiNd(PO3)4. It crystallizes in the monoclinic space group C2/c with the unit cell parameters a=16.386(2), b=7.059(3), c=9.677(2) A, β=126.12(1)°, V=904.2(4) A3 and Z=4. The structure refined from 967 independent reflections leads to R1=0.0167 and wR2=0.0458. The lattice of LiGd(PO3)4 is built of twisted zig–zag chains running along with the b direction and make up of PO4 tetrahedra sharing two corners, connected to the GdO8 and LiO4 polyhedra by common oxygen atoms to form a three-dimensional framework. Differential and thermogravimetric thermal analysis are given. The thermal curve of this compound was recorded and interpreted in agreement with impedance measurements. The ionic conductivity has been measured on pellet of the polycrystalline powder and evaluated as a function of temperature. This phase showed the conductivity of 2×10−6 and 2×10−4 Ω−1 cm−1 at 682 and 951 K, respectively.

The chemical preparation, crystal structure, and infrared absorption spectrum are given for a new cyclotetraphosphate, KGdP4O12. X-ray investigations showed that the newly synthesized compound crystallizes in a monoclinic structure, space group C2/c with the following unit-cell dimensions: a = 7.875(1), b = 12.431(2), c = 10.537(2) A, β = 110.94(1)°, V = 963.4(3) A3, Z = 4, and ρ = 3.532 g cm-3. The structure was solved from 1390 independent reflections with R1 = 2.99 and WR2 = 7.37%, refined with 84 parameters. As in all atomic arrangements, we observe the formation of an infinite network of P4O124- cyclotetraphosphate anions connected with GdO8 polyhedra to form a three-dimensional framework which delimits interesting tunnels where the K+ cations are located. In this structure, the P4O12 ring develops around an inversion center. The reported IR study, recorded at room temperature in the frequency range 400−4000 cm-1, shows some characteristics bands of cyclotetraphosphates.

Single crystals of rubidium gadolinium polyphosphate were grown from a polyphosphate flux. The structure of the title compound is isotypic with CsGd(PO3)4 and consists of helical polyphosphate chains running along the [101] direction with a period of eight PO4 tetra­hedra. These polyphosphate chains are connected by isolated GdO8 dodeca­hedra and irregularly shaped RbO11 polyhedra, forming a three-dimensional framework.