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Four new compounds of 1,3-diethyl-2-thiobarbituric acid (C 8 H 11 N 2 O 2 S, Hdetba) with Rb + , Cs + , Tl + and NH 4 + ions were prepared by Hdetba neutralization with the metal carbonates or ammonium hydroxide in aqueous solution. The colorless crystals have been investigated using X-ray diffraction techniques, differential scanning calorimetry, thermogravimetry and infrared spectroscopy. The coordination compounds of MDetba with M = Rb, Cs and Tl crystallize in the orthorhombic space group P 2 1 2 1 2 1 , but compound NH 4 Detba crystallizes in the triclinic space group P 1 ¯ . The MDetba structures were compared at the molecular and supramolecular levels. The Detba − ion in the NH 4 + compound forms conformer (A) with two diethyl groups on one side of the ion ring, whereas the Detba − ion in the Rb(I), Cs(I) and Tl(I) compounds forms conformer (B) with two diethyl groups on different sides of the ring. The results of IR spectroscopy and thermal analysis are consistent with the X-ray data. [ABSTRACT FROM AUTHOR]

Five new compounds were synthesized by a solvent-free hydrothermal synthesis approach, based on cobalt and iron sulfates and o-, m- or p-phenylenediamine. Their crystal structures were determined by XRPD methods. The compounds were studied by SEM EDX, TG and temperature-dependent XRPD techniques. [Display omitted] Five new compounds were synthesized by a solvent-free synthesis approach, based on cobalt and iron sulfates and 1,2-phenylenediamine (OPD), 1,3-phenylenediamine (MPD) and 1,4-phenylenediamine (PPD) as organic templates and linkers. Their dimensionalities and formulas are: 1D: Fe(OPD) 2 SO 4 (1); 2D: Fe(MPD) 2 SO 4 (2), Co(MPD) 2 SO 4 (3); 3D: Fe(PPD)SO 4 (4) and Co(PPD)SO 4 (5). The crystal structures were determined using data from X-ray powder diffraction measurements (XRPD). The purity and morphology of the compounds were studied by elemental analyses and SEM EDX investigations and their thermal stability was determined by thermogravimetric (TG) and temperature-dependent XRPD techniques. [ABSTRACT FROM AUTHOR]

• Two Strandberg type phosphomolybdates anions with different organic counterions are synthetized. • As the non-protonated anion is more prone to be reduced, we show through the analysis of the two compounds and the literature that the selection of the precursors may be crucial for the stabilization of the suitable anion. • Thermal and electrochemical properties were also investigated. Strandberg-type phosphomolybdate anions are metal-oxide clusters with general formula [H n P 2 Mo 5 O 23 ](6−n)− (n = 0, 1, 2). The protonation/deprotonation of this anion affects its redox properties. Herein, we explain how to select the organic counterions to direct the synthesis towards the non-protonated or protonated anion. The method is illustrated with the synthesis of two new compounds (C 5 H 16 N 2) 3 [P 2 Mo 5 O 23 ]·4H 2 O (1) and (CH 6 N) 4 [H 2 P 2 Mo 5 O 23 ].CH 5 N·4H 2 O (2). The two compounds were characterized by UV–Visible absorption, IR spectroscopy and single crystal X-ray diffraction. Their thermal stabilities and redox properties were also investigated. [ABSTRACT FROM AUTHOR]