The thermally induced hysteretic spin transition (ST) that occurs in the polymeric chain compound [Fe(NH(2)trz)(3)](NO(3))(2) (1) above room temperature (T(c)(upward arrow) = 347 K, T(c)(downward arrow) = 314 K) has been tracked by (57)Fe Mössbauer spectroscopy, SQUID magnetometry, differential scanning calorimetry (DSC), and X-ray powder diffraction (XPRD) at variable temperatures. From the XRPD pattern indexation, an orthorhombic primitive cell was observed with the following cell parameters: a = 11.83(2) A, b = 9.72(1) A, c = 6.361(9) A at 298 K (low-spin state) and a = 14.37(2) A, b = 9.61(4) A, c = 6.76(4) A at 380 K (high-spin state). The enthalpy and entropy variation associated to the ST of 1, have been evaluated by DSC as DeltaH = 23(1) kJ mol(-1) and DeltaS = 69.6(1) J mol(-1) K(-1). These thermodynamic data were used within a two-level Ising like model for the statistical analysis of First Order Reversal Curve (FORC) diagram that was recorded for 1, in the cooling mode. Strong intramolecular cooperative effects are witnessed by the derived interaction parameter of J = 496 K. The crystal structure of [Cu(NH(2)trz)(3)](NO(3))(2).H(2)O (2) was obtained thanks to high quality single crystals prepared by slow evaporation after hydrothermal pretreatment. The catena poly[mu-tris(4-amino-1,2,4-triazole-N1,N2) copper(II)] dinitrate monohydrate (2) crystallizes in the monoclinic space group C2/c, with a = 16.635(6) A, b = 13.223(4) A, c = 7.805(3) A, beta = 102.56(3) degrees, Z = 4. Complex 2 is a 1D infinite chain containing triple N1,N2-1,2,4-triazole bridges with an intra-chain distance of Cu...Cu = 3.903(1) A. A dense H-bonding network with the nitrate counteranion involved in intra-chain and inter-chain interactions is observed. Such a supramolecular network could be at the origin of the unusually large hysteresis loop displayed by 1 (DeltaT approximately 33 K), as a result of an efficient propagation of elastic interactions through the network. This hypothesis is strengthened by the crystal structure of 2 and by the absence of crystallographic phase transition for 1 over the whole temperature range of investigation as shown by XRPD.

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Abstract. The new ternary compounds UP 2 S 6 , UP 2 S 7 , U(P 2 S 6 ) 2 , and U 3 (PS 4 ) 4 were prepared from uranium metal, phosphorus pentasulfide, and sulfur at 700°C. The crystal structures were determined by singlecrystal X-ray diffraction methods. UP 2 S 6 (I) crystallizes in the ZrP 2 S 6 structure type [tetragonal, P4 2 /m, a = 6.8058(7) Å, c = 9.7597(14) Å, Z = 2], which consists of central uranium(IV) atoms coordinated by P 2 S 6 4-anions (staggered conformation). The anions are two-dimensional connectors for four uranium cations arranged in one plane. The structure of UP 2 S 7 (II) [orthorhombic, Fddd, a = 8.9966 (15) ligands, the resulting 3D network contains large pores (diameter approx. 3.5 ϫ 16.7 Å). In the previously reported compound U(P 2 S 6 ) 2 (III) [I4 1 /a, a = 12.8776(9) Å, c = 9.8367(10) Å, Z = 2], the

Solvothermal and classical synthesis with an identical recipe involving 4H-1,2,4-triazol-4-yl acetic acid (HL1) and CdCl 2 afforded two-dimensional (2D) (1) and one-dimensional (2) coordination polymers, respectively. Hexagonal plate-like crystals of [Cd 2 (L1) 2 Cl 2 ] (1), which crystallize in the chiral orthorhombic space group (P2 1 2 1 2 1 ), were obtained in high yield. The 1,2,4-triazole-4-yl acetate (L1) ligand, which has a significant kink in the spacer, leads to the formation of a Cd II complex displaying a 2D single-stranded helical array. The pitch height of the helix is equal to the length of the crystallographic a axis (7.579 Å) which comprises two cadmium atoms and two ligands. Solid-state emission of 1 shows a strong emission band around 465 nm with photoexcitation at 290 nm. Mercury porosimetry measurements reveal pore size distribution with a diameter of 80, 10, and 1 μm. BET shows no preference for N 2(g) but a low H 2(g) adsorption of 4 cm 3 /g. Complex 1, which is constituted by a "soft" nonaromatic network that begins to collapse around 170 °C, was subjected to controlled pyrolysis to produce CdO with morphology and phase selectivity. Texture of the thus obtained pure cubic phase of CdO (β-form) was further tuned with the regulation of the annealing temperature. Crystals of rectangular blocks of [Cd(HL1L1)Cl] 3 2H 2 O (2), which were formed in small quantity, feature a centrosymmetric, monoclinic space group (P2 1 /c). Their crystal structure reveals a one-dimensional linear chain where Cd atoms are connected by a triple bridge made up of one μ-chloride and two μ-N1,N2-1,2,4-triazole HL1 and L1. The coordination polymer charge is balanced by both chloride and the carboxylate group of L1.

The novel uranium thiophosphate CsLiU(PS4)2 has been synthesized by reacting uranium metal, Cs2S, Li2S, S, and P2S5 at 700 °C in an evacuated silica tube. The crystal structure was determined by single‐crystal X‐ray diffraction techniques. CsLiU(PS4)2 crystallizes in the rhombohedral space group R$\bar{3}$c (a = 15.2797(7) Å; c = 28.778(2) Å, V = 5818.7(5) Å3, Z = 18). The structure ofCsLiU(PS4)2 is a unique three‐dimensional U(PS4)22– framework with large tunnels with an approximate diameter of 6.6 Å running parallel to the crystallographic c axis. The tunnels are filled with Cs+ cations. The smaller Li+ cations are located at tetrahedral sites at the periphery of the channels. In the structure of CsLiU(PS4)2 the uranium atoms are coordinated by thiophosphate groups in a pseudotetrahedral fashion, and the PS4 groups act as linear connectors. Topologically, CsLiU(PS4)2 may be regarded a chalcogenide analogue of silicate frameworks, with the uranium atoms and PS4 groups replacing silicon and oxygen atoms. Alternatively, CsLiU(PS4)2 may be viewed as a coordination polymer, which is formed in salt melts by the solid state equivalent of the “self‐assembly” reactions in solution. Magnetic susceptibility measurements indicated Curie–Weiss‐type behavior between 4 K and 300 K. The μeff of 2.83 μB at 300 K is in agreement with an f2 configuration of U4+.