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Thermal nonradiative depopulation processes of excited levels significantly influence the potential application of phosphors. The high efficiency of thermal quenching of luminescence can limit a phosphor's potential applications as well as reduce the temperature range in which such a material can be used. This work presents a new strategy of shifting of usable temperature range of luminescent thermometer based on Eu3+ ion emission that the molar ratio of (AsO4)3− in respect to (VO4)3− increases in YVxAs1−xO4 host material. Consequently, the thermometric performance of the luminescence thermometer based on the single band intensity ratio corresponding to the 5D0 → 7F1 of Eu3+ ions upon optical excitations matching to the 1A2(1T1) → 1B1(1T2) and 1E(1T1) → 1B1(1T2) electronic transition of (VO4)3− group can be optimized. As shown, the use of YV0.25As0.75O4:Eu3+ has an extended usable temperature range in respect to YVO4:Eu3+. This improvement, coupled with its high sensitivity (>1% K−1) make YV0.25As0.75O4:Eu3+ a more stable material for luminescence thermometer applications. The presented strategy for modulating the thermal properties of luminescent thermometers through the introduction of the (AsO4)3− groups is a step towards designing thermometers with on-demand thermometric performance. [ABSTRACT FROM AUTHOR]

By means of alternating current-electrochemical synthesis starting from a mixture of 2-imino-3-(prop-2-en-1-yl)-1,3-thiazolidin-4-one (3-allylpseudothiohydantoin, napt) and 2-allylamino-1,3-thiazol-4(5H)-one (allylaminopseudothiohydantoin, aapt) hydrochlorides and corresponding copper(II) salts five new π-complexes, [Cu(napt)Cl] (1), [Cu2(aapt)2Cl]NO3(2), [Cu2(aapt)2Cl]BF4(3), [Cu2(aapt)2Cl]ClO4(4) and [Cu2(aapt)2Cl]2SiF6·2H2O (5), were obtained and studied by X-ray single crystal diffraction and IR-spectroscopy. Napt and aapt molecules are selectively coordinated to Cu+depending on the anion type. In crystals of1and5, the organic ligands are attached to the metal in a chelating N,(C=C)-bidentate mode. The aapt molecule in2-4acts as a tridentate chelating ligand, being coordinated to the copper(I) ion through the heterocyclic N atom, carbonyl O atom, and C=C bond of allyl group, forming an original cationic [Cu2(aapt)2Cl]+fragment with both a bridging Cl–ion and O atom of the C=O group. In the presence of the doubly charged SiF62–anion, Cu(I) in5prefers to be bonded with two bridging Cl–ions, rather than the C=O group, causing [Cu2(aapt)2Cl]+units to associate into the infinite cationic chains. Crystals of3and4are the first known examples of the simultaneous BF4–/Cl–or ClO4–/Cl–participation in copper(I) π-complex formation. [ABSTRACT FROM PUBLISHER]

The crystal structure has been determined for (CH3NH3)2[KCo(CN)6] at temperatures 100 and 443 K. It crystallizes in the monoclinic space group C2/c (LT) and in the cubic one Fm3̅m (HT). The dielectric response has been investigated for single crystals of pure K3[A′(CN)6] and guest–hosts of (CH3NH3)2[KA′(CN)6], where A′ is a trivalent metal, Co or Fe. Their dielectric properties were measured in the frequency range between 135 Hz and 2 MHz in a wide temperature range between 200 and 460 K. The anisotropy of the electric permittivity for single crystals of (CH3NH3)2[KCo(CN)6] was analysed in terms of the crystal structure. The relaxation processes were observed in the case of the pure host K3Fe(CN)6 and the guest/host crystal (CH3NH3)2[KFe(CN)6]. The activation energies of the dielectric relaxation have been estimated to be equal to 44 and 40 kJ mol−1 for (CH3NH3)2[KFe(CN)6] and K3Fe(CN)6, respectively. The mechanism of the phase transitions found at 425 K and 421 K for (CH3NH3)2[KFe(CN)6] and (CH3NH3)2[KCo(CN)6], respectively, has been postulated. From the dielectric losses the value of the electric ac conductivity has been estimated and analyzed in terms of the activation process of the current carriers. [ABSTRACT FROM AUTHOR]

The multi component Fe74Hf4Ta1Cu1Gd1LaxSi15-xCu1Gd1LaxSi15-xB4 (x=0;7) alloys are promising candidates in the search for materials with unusual mechanical and magnetic properties. Amorphous nature of melt-spun samples was confirmed by X-ray diffractometry and Mössbauer spectroscopy. The X-ray diffraction patterns revealed a distinct amorphous halo. The low-field components of magnetic hyperfine field distributions on iron nuclei are observed in the Mssbauer spectra, with average hyperfine field values of 19.9 and 15.7 T for x=0 and x=7, respectively. Coercivity studied by vibrating sample magnetometer was about 12 A/m for x=0 and 82 A/m for x=7 at 300 K and about 600 A/m for x=0 and 1200 A/m for x=7 at 400 K. Remanence also changed with temperature, amounting to 0.64 T for x=0 and 0.36 T for x=7 at 300 K, while at 400 K it was 0.43 and 0.11 T for x=0 and x=7, respectively. It is shown that La addition has beneficial effect of shifting the Curie point towards lower temperatures together with the increase of magnitude of magnetization. [ABSTRACT FROM AUTHOR]

The crystal structure has been determined for (CH3NH3)2[KCo(CN)6] at temperatures 100 and 443 K. It crystallizes in the monoclinic space group C2/c (LT) and in the cubic one Fm3̅m (HT). The dielectric response has been investigated for single crystals of pure K3[A′(CN)6] and guest–hosts of (CH3NH3)2[KA′(CN)6], where A′ is a trivalent metal, Co or Fe. Their dielectric properties were measured in the frequency range between 135 Hz and 2 MHz in a wide temperature range between 200 and 460 K. The anisotropy of the electric permittivity for single crystals of (CH3NH3)2[KCo(CN)6] was analysed in terms of the crystal structure. The relaxation processes were observed in the case of the pure host K3Fe(CN)6 and the guest/host crystal (CH3NH3)2[KFe(CN)6]. The activation energies of the dielectric relaxation have been estimated to be equal to 44 and 40 kJ mol−1 for (CH3NH3)2[KFe(CN)6] and K3Fe(CN)6, respectively. The mechanism of the phase transitions found at 425 K and 421 K for (CH3NH3)2[KFe(CN)6] and (CH3NH3)2[KCo(CN)6], respectively, has been postulated. From the dielectric losses the value of the electric ac conductivity has been estimated and analyzed in terms of the activation process of the current carriers. [ABSTRACT FROM AUTHOR]

A series of zinc aryloxides, [Zn 4 (sal-Me) 8 ]⋅2.5(C 7 H 8 ) (1), [Zn 4 (sal-Me) 8 ]⋅CH 2 Cl 2 (2), [Zn 4 (μ 3 -OR) 2 (sal-R) 6 ] (3) (for R=Me (0.51), Et (0.49)), [Zn 4 (μ 3 -OMe) 4 (sal-Me) 4 (HOMe) 4 ] (4), [Zn(sal-Me) 2 (py) 2 ]⋅THF (5), {[Zn(sal-Me) 2 (tmbpy)] ⋅ 2(C 6 H 5 CH 3 )} n (6), [Zn 2 (sal-Me) 2 (THF) 2 Cl 2 ] ⋅ 0.5(C 6 H 5 CH 3 ) (7), and [Zn 4 (μ 3 -OMe) 2 (sal-Me) 4 Cl 2 ] (8) (Hsal-Me=methyl salicylate, py=pyridine, tmbpy=4,4'-trimethylenedipyridine) were obtained that have different nuclearities and central core topologies and contain ligands of different basicity and coordination abilities., (© 2024 Wiley-VCH GmbH.)

The synthesis of [2]rotaxanes stoppered with one or two dipyrromethane groups has opened a route for the construction of mechanically interlocked molecules incorporating various porphyrinoid stations. The exploitation of those precursors allowed the creation of [3]rotaxanes and [2]catenanes based on the calix[4]phyrin motif, presenting intriguing molecular dynamics. The intrinsic flexibility of the porphyrinoid allowed the introduction of a new type of molecular motion within the rotaxanes, termed fluttering. The latter involved a bending of the axle, interconverting two angular-shaped stereoisomers of the rotaxane through a planarised transition state. Simple chemical transformations, i.e. methylation and (de)protonation of the [3]rotaxane and [2]catenane allowed controllable transformations within the conformationally flexible calix[4]phyrin-incorporated mechanically interlocked porphyrinoids., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The synthesis of four 4-(carbazolyl- R -benzoyl)-5-CF 3 -1 H -1,2,3-triazoles with extra groups ((3-methyl)-phenyl-, 4-fluorophenyl-, quinolinyl-, or (3-trifluoromethyl)-phenyl-) in the acceptor fragment has been reported. The effects of substituents with different electron-withdrawing strengths on the thermal, electrochemical, photophysical, and electroluminescence properties of the synthesized compounds are discussed. The results of X-ray analyses and density functional theory (DFT) calculations support unusual molecular packing and electronic properties. The compounds are capable of glass formation with glass transition temperatures ranging from 54-84 °C. Ionization potentials of the compounds are in the range of 5.98-6.22 eV and electron affinities range from 3.09 to 3.35 eV. Under ultraviolet excitation, the neat films of the compounds exhibit blue emission with photoluminescence quantum yields ranging from 18 to 27%. The films of selected compounds are used for the preparation of host-free light-emitting layers of organic light-emitting diodes with very simple device structures and an external quantum efficiency of 4.6%., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The linking of two dinuclear macrocyclic units of large triphenolic hexaazamine by two carbonate anions results in the formation of dimeric tetranuclear Sm(III), Eu(III) and Gd(III) complexes. These complexes were initially obtained serendipitously by fixation of atmospheric carbon dioxide and subsequently obtained in a rational way by the application of carbonate salts. The X-ray crystal structures of these isomorphic complexes show highly folded conformation of the macrocycle. This type of conformation is also confirmed by 2D NMR spectra of the Sm(III) complex. The ESI-MS and NMR spectra reveal also that these carbonate complexes exist in solution in two different forms that are in a concentration-dependent dynamic equilibrium.

Copper(I) π-coordination compounds with allyl derivatives of azoles are an interesting subject of current research, but Cu I π-complexes with other transition-metal ions incorporated in the structure have been virtually uninvestigated. The present work is directed toward the synthesis and structural characterization of the novel heterometallic Cu I /Fe II π-complex di-μ 2 -chlorido-1:2κ 2 Cl;2:3κ 2 Cl-tetrakis[μ 2 -5-(prop-2-en-1-ylsulfanyl)-1,3,4-thiadiazol-2-amine]-1:2κ 2 N 4 :N 3 ;1(η 2 ),κN 4 :2κN 3 ;2:3κ 2 N 3 :N 4 ;2κN 3 :3(η 2 ),κN 4 -dicopper(I)iron(II) tetrachloridoferrate(II), [Cu 2 FeCl 2 (C 5 H 7 N 3 S 2 ) 4 ][FeCl 4 ] (1). The structure of the 5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine (Pesta, C 5 H 7 N 3 S 2 ) ligand is also presented. The cationic substructure in 1 consists of one Fe II and two Cu I ions bridged by two chloride ions along with two σ,σ- and two π,σ-coordinated ligands, whereas the anionic part is built of isolated tetrahedral [FeCl 4 ] 2- ions. π-Coordination of the Pesta allyl group to the Cu I ions prevents agglomeration of the inorganic Cu-Cl-Fe-Cl-Cu part into infinate chains. An energy framework computational analysis was performed for Pesta.

The novel π-coordination compound [Cu I (m-dmphast)NO 3 ], where m-dmphast = 5-(allylthio)-1-(3,5-dimethylphenyl)-1H-tetrazole, is characterized using single-crystal X-ray diffraction and crystallizes in a noncentrosymmetric space group. Additionally, for the first time in this group of materials, the streaks of X-ray diffuse scattering in the reciprocal space sections were observed and described. This gave the possibility for a deeper insight into the local structure of the title compound. The conjecture about the origin of diffuse scattering was derived from average structure solution. It was then confirmed using the local structure modelling. The extended [Cu(m-dmphast)NO 3 ] ∞ chains, connected by weak interactions, produce layers which can exist in two enantiomeric forms, one of which predominates.

Two imidazolium hypodiphosphates, (C 3 H 5 N 2 )(H 3 P 2 O 6 ) (I) and (C 3 H 5 N 2 ) 2 (H 2 P 2 O 6 ) (II), have been synthesized and structurally characterized. In both metal-free organic-inorganic hybrids (I) and (II), the hypodiphosphate mono- and dianions, (H 3 P 2 O 6 ) - and (H 2 P 2 O 6 ) 2- , form hydrogen-bonded frameworks of different types, to which the organic cations are linked via N-H...O and C-H...O hydrogen bonds. The purity of the compounds was confirmed by powder X-ray diffraction. Differential scanning calorimetry of compound (I) revealed two structural phase transitions: continuous at 311.8 K [cooling/heating; from high-temperature phase (HTP) to room-temperature phase (RTP)] and a discontinuous one at 287.9/289.2 K [RTP → low-temperature phase (LTP)]. Compound (I) is characterized in a wide temperature range by single-crystal and powder X-ray diffraction methods. Crystal structures of high- and low-temperature phases are determined, which show orthorhombic (HTP, Pnna, No. 52) → monoclinic (LTP, P2 1 /n11, No. 14, a-axis doubled) structural change on cooling with an intermediate incommensurately modulated phase (RTP). Dynamic properties of polycrystalline (I) were studied by means of dielectric spectroscopy. The dielectric behaviour is explained by the motion of imidazolium cations.

The organic-inorganic hybrid compound 4-aminopyridinium tetraaquabis(sulfato)iron(III), (C 5 H 7 N 2 )[Fe III (H 2 O) 4 (SO 4 ) 2 ] (4apFeS), was obtained by slow evaporation of the solvent at room temperature and characterized by single-crystal X-ray diffraction in the temperature range from 290 to 80 K. Differential scanning calorimetry revealed that the title compound undergoes a sequence of three reversible phase transitions, which has been verified by variable-temperature X-ray diffraction analysis during cooling-heating cycles over the temperature ranges 290-100-290 K. In the room-temperature phase (I), space group C2/c, oxygen atoms from the closest Fe-atom environment (octahedral) were disordered over two equivalent positions around a twofold axis. Two intermediate phases (II), (III) were solved and refined as incommensurately modulated structures, employing the superspace formalism applied to single-crystal X-ray diffraction data. Both structures can be described in the (3+1)-dimensional monoclinic X2/c(α,0,γ)0s superspace group (where X is ½, ½, 0, ½) with modulation wavevectors q = (0.2943, 0, 0.5640) and q = (0.3366, 0, 0.5544) for phases (II) and (III), respectively. The completely ordered low-temperature phase (IV) was refined with the twinning model in the triclinic P{\overline 1} space group, revealing the existence of two domains. The dynamics of the disordered anionic substructure in the 4apFeS crystal seems to play an essential role in the phase transition mechanisms. The discrete organic moieties were found to be fully ordered even at room temperature.

Thermal analysis, X-ray diffraction and temperature-dependent IR spectroscopy were used to study the dehydration process of crystalline DL-phenylglycinium trifluoromethanesulfonate monohydrate (PGTFH), C 8 H 10 NO 2 + ·CF 3 SO 3 - ·H 2 O. PGTFH dehydrates in one step centred at 353 K and crystallizes in the monoclinic space group C2/c, whereas the anhydrous compound (PGTF) crystallizes in the triclinic space group P-1. The dehydration process in PGTFH is preceded by a weakening of both the noncovalent aromatic-aromatic interactions and the packing contacts. This process is accompanied by the breakage of medium-strength O-H...O hydrogen bonds between ions inside layers and a reorganization of the ions within the layers. This reorganization results in the formation of two different ion pairs (DL-phenylglycinium trifluoromethanesulfonate) and the formation of a new hydrogen-bond network. The dehydration process does not destroy the nature of the crystal structure. Both crystals, i.e. hydrated and anhydrous, have a layered structure, although the layers of each crystal are arranged somewhat differently.

The novel polar material 2-amino-3-nitropyridinium hydrogen sulfate, C 5 H 6 N 3 O 2 (HSO 4 ) (abbreviated as 2A3NP-HS), was obtained and structurally characterized by means of single-crystal X-ray diffraction. At room temperature, 2A3NP-HS crystallizes as a non-centrosymmetric disordered phase (I) in the orthorhombic Pna2 1 space group. On cooling below 298 K, 2A3NP-HS undergoes a reversible phase transition to phase (II) with the monoclinic non-centrosymmetric P2 1 space group. This transition might be classified as an `order-disorder' type. The structural details in both phases are analysed. Additionally, for phase (I), in the 304-365 K temperature range, diffuse scattering was found to be present in the form of elongated streaks parallel to the a* direction. This can be unravelled when implementing a short-range order affecting anionic cationic ribbons occurring in the structure, with correlations acting both in the a-direction and in the bc-plane. The results of Monte Carlo simulations, adapting a two-dimensional Ising-type model, reveal the formation of domains, which are b-elongated and thin along a. Locally, the stacking of the ribbons in the domains reflects the ordered arrangement observed in the low-temperature monoclinic phase (II).

The crystal structure has been determined for (CH 3 NH 3 ) 2 [KCo(CN) 6 ] at temperatures 100 and 443 K. It crystallizes in the monoclinic space group C2/c (LT) and in the cubic one Fm3[combining macron]m (HT). The dielectric response has been investigated for single crystals of pure K 3 [A'(CN) 6 ] and guest-hosts of (CH 3 NH 3 ) 2 [KA'(CN) 6 ], where A' is a trivalent metal, Co or Fe. Their dielectric properties were measured in the frequency range between 135 Hz and 2 MHz in a wide temperature range between 200 and 460 K. The anisotropy of the electric permittivity for single crystals of (CH 3 NH 3 ) 2 [KCo(CN) 6 ] was analysed in terms of the crystal structure. The relaxation processes were observed in the case of the pure host K 3 Fe(CN) 6 and the guest/host crystal (CH 3 NH 3 ) 2 [KFe(CN) 6 ]. The activation energies of the dielectric relaxation have been estimated to be equal to 44 and 40 kJ mol -1 for (CH 3 NH 3 ) 2 [KFe(CN) 6 ] and K 3 Fe(CN) 6 , respectively. The mechanism of the phase transitions found at 425 K and 421 K for (CH 3 NH 3 ) 2 [KFe(CN) 6 ] and (CH 3 NH 3 ) 2 [KCo(CN) 6 ], respectively, has been postulated. From the dielectric losses the value of the electric ac conductivity has been estimated and analyzed in terms of the activation process of the current carriers.

As an important class of heterocyclic compounds, 1,3,4-thiadiazoles have a broad range of potential applications in medicine, agriculture and materials chemistry, and were found to be excellent precursors for the crystal engineering of organometallic materials. The coordinating behaviour of allyl derivatives of 1,3,4-thiadiazoles with respect to transition metal ions has been little studied. Five new crystalline copper(I) π-complexes have been obtained by means of an alternating current electrochemical technique and have been characterized by single-crystal X-ray diffraction and IR spectroscopy. The compounds are bis[μ-5-methyl-N-(prop-2-en-1-yl)-1,3,4-thiadiazol-2-amine]bis[nitratocopper(I)], [Cu 2 (NO 3 ) 2 (C 6 H 9 N 3 S) 2 ], (1), bis[μ-5-methyl-N-(prop-2-en-1-yl)-1,3,4-thiadiazol-2-amine]bis[(tetrafluoroborato)copper(I)], [Cu 2 (BF 4 ) 2 (C 6 H 9 N 3 S) 2 ], (2), μ-aqua-bis{μ-5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine}bis[nitratocopper(I)], [Cu 2 (NO 3 ) 2 (C 5 H 7 N 3 S 2 ) 2 (H 2 O)], (3), μ-aqua-(hexafluorosilicato)bis{μ-5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine}dicopper(I)-acetonitrile-water (2/1/4), [Cu 2 (SiF 6 )(C 5 H 7 N 3 S 2 ) 2 (H 2 O)]·0.5CH 3 CN·2H 2 O, (4), and μ-benzenesulfonato-bis{μ-5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine}dicopper(I) benzenesulfonate-methanol-water (1/1/1), [Cu 2 (C 6 H 5 O 3 S)(C 5 H 7 N 3 S 2 ) 2 ](C 6 H 5 O 3 S)·CH 3 OH·H 2 O, (5). The structure of the ligand 5-methyl-N-(prop-2-en-1-yl)-1,3,4-thiadiazol-2-amine (Mepeta), C 6 H 9 N 3 S, was also structurally characterized. Both Mepeta and 5-[(prop-2-en-1-yl)sulfanyl]-1,3,4-thiadiazol-2-amine (Pesta) (denoted L) reveal a strong tendency to form dimeric {Cu 2 L 2 } 2+ fragments, being attached to the metal atom in a chelating-bridging mode via two thiadiazole N atoms and an allylic C=C bond. Flexibility of the {Cu 2 (Pesta) 2 } 2+ unit allows the Cu I atom site to be split into two positions with different metal-coordination environments, thus enabling the competitive participation of different molecules in bonding to the metal centre. The Pesta ligand in (4) allows the Cu I atom to vary between water O-atom and hexafluorosilicate F-atom coordination, resulting in the rare case of a direct Cu I ...FSiF 5 2- interaction. Extensive three-dimensional hydrogen-bonding patterns are formed in the reported crystal structures. Complex (5) should be considered as the first known example of a Cu I (C 6 H 5 SO 3 ) coordination compound. To determine the hydrogen-bond interactions in the structures of (1) and (2), a Hirshfeld surface analysis has been performed.

Four copper(I) π-complexes: [Cu(Hapn)NO3]NO3 (1), [Cu(Hapn)(H2O)2]SiF6 (2), [Cu(Hapn)(H2O)BF4]BF4·H2O (3) and [Cu(Hapn)(NH2SO3)2] (4) were prepared using alternating-current electrochemical technique, starting from alcohol solutions of 3-(prop-2-en-1-ylamino)propanenitrile (apn) titrated with appropriate acid and copper(II) salts (Cu(NO3)2 · 3H2O, CuSiF6 · 4H2O, Cu(BF4)2 · 6H2O or Cu(NH2SO3)2 · xH2O, respectively). Obtained compounds were characterized by single-crystal X-ray diffraction and partially by IR spectroscopy. In the structures of complexes 1, 2 and 4 Cu(I) cation possesses a tetrahedral environment formed by the C=C bond of one organic cation Hapn, the N atom of cyano group from another Hapn moiety, and two O atoms (from NO3- anions in 1, from H2O molecules in 2) or N atoms (NH2SO3- anions in 4). In compound 3 strongly pronounced trigonal-pyramidal coordination environment of Cu(I) is formed by a mid-point of C=C-bond of one Hapn cation, nitrogen atom (of cyano group) of another Hapn unit, O atom of H2O molecule in the basal plane, and F atom of BF4- anion at the apical position.

Hybrid materials, fabricated by the combination of inorganic and organic components, have potential applications in chemistry and are endowed with the advantages of both building elements. There are several types of intermolecular interactions present in these hybrid compounds, including electrostatic forces, π-π stacking and hydrogen-bonding interactions, the latter playing an important role in the construction of three-dimensional architectures and stabilizing supramolecular crystal structures. Analysis of the intermolecular interactions and their influence on packing modes therefore requires focused scientific attention. Four new organic-inorganic salts, namely 2-amino-4-methyl-3-nitropyridinium hydrogen sulfate, C 6 H 8 N 3 O 2 + ·HSO 4 - , bis(2-amino-4-methyl-3-nitropyridinium) sulfate, 2C 6 H 8 N 3 O 2 + ·SO 4 2- , 2-amino-3-methylpyridinium hydrogen sulfate, C 6 H 9 N 2 + ·HSO 4 - , and bis(2-amino-3-methylpyridinium) sulfate monohydrate, 2C 6 H 9 N 2 + ·SO 4 2- ·H 2 O, have been synthesized and characterized by X-ray diffraction. The crystal structures are stabilized by intra- and intermolecular hydrogen bonds, as well as by weak π-π stacking and lp-π (lp is lone pair) interactions. Hirshfeld surface analysis was employed in order to study intermolecular interactions.

The chemistry of organically templated metal sulfates has attracted interest from the materials science community and the development of synthetic strategies for the preparation of organic-inorganic hybrid materials with novel structures and special properties is of current interest. Sulfur-oxygen-metal linkages provide the possibility of using sulfate tetrahedra as building units to form new solid-state materials. A series of novel organically templated metal sulfates of 2-aminopyridinium (2ap) with aluminium(III), cobalt(II), magnesium(II), nickel(II) and zinc(II) were obtained from the respective aqueous solutions and studied by single-crystal X-ray diffraction. The compounds crystallize in centrosymmetric triclinic unit cells in three structure types: type 1 for 2-aminopyridinium hexaaquaaluminium(III) bis(sulfate) tetrahydrate, (C5H7N2)[Al(H2O)6](SO4)2·4H2O, (I); type 2 for bis(2-aminopyridinium) tris[hexaaquacobalt(II)] tetrakis(sulfate) dihydrate, (C5H7N2)2[Co(H2O)6]3(SO4)4·2H2O, (II), and bis(2-aminopyridinium) tris[hexaaquamagnesium(II)] tetrakis(sulfate) dihydrate, (C5H7N2)2[Mg(H2O)6]3(SO4)4·2H2O, (III); and type 3 for bis(2-aminopyridinium) hexaaquanickel(II) bis(sulfate), (C5H7N2)2[Ni(H2O)6](SO4)2, (IV), and bis(2-aminopyridinium) hexaaquazinc(II) bis(sulfate), (C5H7N2)2[Zn(H2O)6](SO4)2, (V). The templating role of the 2ap cation in all of the reported crystalline substances is governed by the formation of characteristic charge-assisted hydrogen-bonded pairs with sulfate anions and the presence of π-π interactions between the cations. Additionally, both coordinated and uncoordinated water molecules are involved in hydrogen-bond formation. As a consequence, extensive three-dimensional hydrogen-bonding patterns are formed in the reported crystal structures.

(C3N2H5)2[CoCl4] (ICC) was characterized in a wide temperature range by the single-crystal X-ray diffraction method. Differential scanning calorimetry revealed two structural phase transitions: continuous at 245.5 K (from phase I to II) and a discontinuous one at 234/237 K (cooling/heating) (II → III). ICC adopts monoclinic space groups C2/c and P21/c in phase (I) and (III), respectively. The intermediate phase (II) appears to be incommensurately modulated. Dynamic properties of polycrystalline ICC were studied by means of dielectric spectroscopy and proton magnetic resonance ((1)H NMR). The presence of a low frequency dielectric relaxation process in phase III reflects libration motion of the imidazolium cations. The temperature dependence of the (1)H spin-lattice relaxation time indicated two motional processes with similar activation energies that are by about an order of magnitude smaller than the activation energy obtained from dielectric studies. There are no abrupt changes in the (1)H relaxation time at the phase transitions indicating that the dynamics of the imidazolium rings gradually varies with temperature; that is, it does not change suddenly at the phase transition. Negative values of the Weiss constant and the intermolecular exchange parameter were obtained, confirming the presence of a weak antiferromagnetic interaction between the nearest cobalt centers. Moreover, the magnitude of zero field splitting was determined. The AC susceptibility measurements show that a slow magnetic relaxation is induced by small external magnetic field.

In the title molecular salt, 3C5H12N(+)·HSO4 (-)·SO4 (2-), each cation adopts a chair conformation. In the crystal, the hydrogen sulfate ion is connected to the sulfate ion by a strong O-H⋯O hydrogen bond. The packing also features a number of N-H⋯O hydrogen bonds, which lead to a three-dimensional network structure. The hydrogen sulfate anion accepts four hydrogen bonds from two cations, whereas the sulfate ion, as an acceptor, binds to five separate piperidinium cations, forming seven hydrogen bonds.

A new organic-inorganic hybrid compound, penta-morpholinium hexa-hydrogen hexa-molybdoferrate(III) sulfate 3.5-hydrate, (C4H10NO)5[Fe(III)(OH)6Mo6O18](SO4)·3.5H2O, was obtained from an aqueous solution. The polyoxidomolybdate (POM) anion is of the Anderson β-type with a central Fe(III) ion. Three of five crystallographically independent morpholinium cations are disordered over two sets of sites. An intricate network of inter-molecular N-H⋯O and O-H⋯O inter-actions between cations, POMs, sulfate anions and non-coordinating water mol-ecules creates a three-dimensional network structure.

The title compound, (C5H7N2)2[Cu(H2O)6](SO4)2·4H2O [systematic name: bis(2-aminopyridinium) hexaaquacopper(II) bis(sulfate) tetrahydrate], comprises axially elongated hexa-aqua-coordinated octa-hedral Cu(II) ions located on an inversion centre, non-coordinating sulfate anions, 2-amino-pyridinium cations and lattice water mol-ecules. The crystal structure is built of successive inorganic and organic layers extending parallel to (001) that are connected by an extensive three-dimensional hydrogen-bonded network of the type O-H⋯O and N-H⋯O, as well as π-π inter-actions [centroid-centroid distance 3.4140 (14) Å, offset 0.277 Å].

[Bis(tri-methyl-sil-yl)amino](tert-butyl-imino)-thio-phospho-rane reacts in benzene with isopropyl alcohol via 1,2-addition of an (i) PrO-H bond across the P=N bond, resulting in the title compound, C13H35N2OPSSi2. In the mol-ecule, the P atom possesses a distorted tetra-hedral environment involving two N atoms from (Me3Si)2N- and (t) BuNH- groups, one O atom from an (i) PrO group and one S atom, therefore the mol-ecule has a stereocenter on the P atom but crystal symmetry leads to a racemate. In the crystal, a pair of enanti-omers form a centrosymmetric dimer via a pair of N-H⋯S hydrogen bonds.