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Aims Right heart catheterization (RHC) is indicated in all candidates for heart transplantation (HT). An acute vasodilator challenge is recommended for those with pulmonary hypertension (PH) to assess its reversibility. The effects of inhaled nitric oxide (iNO) on pulmonary and systemic haemodynamics have been reported only in small series. Our purpose was to describe the response to iNO in a larger population and its potential clinical implications. Methods and results From 210 RHC procedures performed between 2010 and 2019, vasodilator challenge with iNO was used in 108 patients, of which 66 had advanced heart failure undergoing assessment for HT (55±11 years old; 74.2% male gender; 43.9% ischaemic cardiomyopathy; left ventricular ejection fraction 28.4 ± 11,4%; and peak VO2 12.1 ± 3.0 mL/kg/min). iNO was administered through a tight‐fitting facial mask regardless of baseline pulmonary pressures. Clinical endpoints (all‐cause mortality and acute right heart failure) were assessed according to baseline haemodynamic findings over the available follow‐up period. There were no side effects from iNO administration. Typical response consisted of a reduction in pulmonary vascular resistance, consequent to an increase in left ventricular filling pressures, no significant change in mean pulmonary artery pressure (resulting in a lower mean transpulmonary gradient) and a mild increase in cardiac ouput. Pulmonary arterial compliance increased significantly, whereas systemic vascular resistance was only mildly affected. In five cases (7.6%), pulmonary vascular resistance increased paradoxically. All‐cause mortality and post‐HT right heart failure events were overall low and similar in patients without PH or reversible PH. Conclusions Vasodilator challenge with iNO is safe in advanced heart failure patients undergoing RHC prior to HT listing. It produces a reasonably predictable haemodynamic response, which occurs predominantly at the pulmonary circulation level. Clinical implications of iNO‐induced reversibility may be relevant, but further systematic validation is warranted in larger cohorts.

Glycerol, ethylene glycol, and quicklime were used as alternative dehydrating agents to obtain anhydrous bioethanol from sweet potato. The assay conditions were standardized using high bioethanol grades. For organic reagents, three volumetric ratios were studied whereas for quicklime, five concentrations were evaluated. Quicklime led to the highest bioethanol purity of 99.4 degrees GL, followed by glycerol and ethylene glycol, reaching 96.9 and 96.6 degrees GL, respectively. Glycerol and ethylene glycol were reused for 4 cycles with negligible loss of efficiency; however, the yield decreased by up to 8 %.

Although alkaline hydrolysis emerges as an alternative process to treat healthcare waste (HCW), information about its emissions is scarce, namely as regards effluents production. This work aims to characterize the effluents from alkaline hydrolysis tests with samples of components usually present in HCW, under a temperature of 110°C and with 1 M NaOH aqueous solutions. Some of the regulatory parameters for discharging effluents were determined; also, tests for assessing aerobic and anaerobic biodegradation of those effluents were carried out. The effluents showed values lower than threshold values for almost all the parameters except pH, total nitrogen, TOC, COD and BOD5. Although with high organic load, the effluents from discarded medical components (DMC) and animal tissues (AT) showed a percentage of aerobic biodegradation of 50.5 and 52.9%, respectively. The anaerobic biodegradability obtained for the effluents from DMC were 22.3 and 42.2% for those with AT.

Three salts of the dissymmetrical TTF derivative cyanobenzene-ethylenedithio-tetrathiafulvalene (CNB-EDT-TTF) with different anions, namely, (CNB-EDT-TTF)2[M(mnt)2] [M = Ni (1), Au (2); mnt = maleonitriledithiolate] and (CNB-EDT-TTF)FeBr4 (3) were prepared and characterized by single-crystal X-ray diffraction, magnetic susceptibility, and electrical conductivity measurements. Compounds 1 and 2 are isostructural with a crystal structure characterized by segregated chains of side-by-side donor dimers and acceptors, and compound 3 presents donors in dimerized stacks. In spite of the different structural types and stoichiometries, all of these compounds have C–N···H pairing interactions associated with R22(10) synthons between donors in nearby chains. All compounds are poor semiconductors, and the magnetic susceptibility of 1 is dominated by the contribution of the paramagnetic [Ni(mnt)2] anions with small antiferromagnetic interactions. The magnetic susceptibility of 3 is dominated by the paramagnetic FeBr4 anions and follows a Curie–Weiss law with a Weiss temperature θ = –19 K, which denotes significant antiferromagnetic interactions that are most likely mediated by the donors.

α-Methyldithiophene–tetrathiafulvalene (α-mDT-TTF), the first alkyl-substituted thiophene–tetrathiafulvalene electronic donor, and some of its charge-transfer salts were explored. The crystal structure of α-mDT-TTF is composed of molecular stacks aligned parallel to each other. Its cyclic voltammetry shows higher electron-donor ability than the unsubstituted analogue. This material was employed as a semiconductor in an organic field-effect transistor and showed a mobility of 4 × 10–4 cm2 V–1 s–1. Two charge-transfer salts of this donor with [M(mnt)2]– anions (mnt = maleonitriledithiolate), M = Co and Au, were obtained by electrocrystallization; they present unusual stoichiometries: (α-mDT-TTF)[Co(mnt)2] and (α-mDT-TTF)3[Au(mnt)2]2. In the cobalt compound, the donor molecules are fully oxidized and the Co complex is dimerized; it presents semiconducting behavior (7 × 10–3 S cm–1). The gold compound is composed of alternating stacks of donor trimers and pairs of anions.

Background and aim Transradial approach (TRA) is being used increasingly as the preferential vascular access site for both diagnostic and interventional procedures. However, concerns have risen about the risk of clinically meaningful neurologic complications. We aimed to assess the association between the risk of stroke/transient ischemic attack (TIA) and the transradial (vs. transfemoral) approach. Methods and Results Data from 16,710 cases included in a single centre prospective registry between January 2006 and November 2012 was analyzed. Radial procedures were considered as those in which the radial access was used either primarily (n = 4,195) or after conversion (n = 36). Potential cases with neurologic events were targeted by cross-referencing patients who underwent both cardiac catheterization and cranial-computed tomography (cranial-CT) during the same admission episode (n = 67). Procedure-related events were defined as a definitive non-CABG related stroke/TIA occurring within 48 hr of the procedure. TRA increased from 0.7% in 2006 to 75% in 2012. Total incidence of stroke/TIA was 0.16% and did not change over the study period (P = 0.26). There was no significant difference in stroke/TIA rates between groups (0.165% vs. 0.160%; P = 1.0). After correction for baseline differences and propensity score matching, TRA was not an independent predictor of stroke/TIA (OR 1.21; 95% CI 0.49–2.98 and 1.3; 95% CI 0.55–3.54, respectively). Results were consistent in pre-specified sub-groups according to age (≥65 y.o. vs. younger), gender, interventional vs. diagnostic and ACS vs. stable. Conclusion Rates of documented stroke/TIA were low. Our observational study suggests that widening the use of the TRA is not associated with an increased risk of clinically relevant procedure-related neurologic complications. © 2015 Wiley Periodicals, Inc.

Transition metal complexes based on the new ligand 5-methylthiophene-2,3-dithiolate (α-mtpdt) and Au, Ni, Fe, Co, Cu Pt and Pd were prepared as tetraalkylammonium and tetraarylphosphonium salts and characterised by cyclic voltammetry, X-ray diffraction, electron paramagnetic resonance (EPR) spectroscopy and magnetic susceptibility measurements. Except for the Cu complex, which forms a four-metal cluster [Cu4(α-mtpdt)3]2–, the metals form complexes of the general formula [M(α-mtpdt)2]. With Au, Ni and Fe, the complexes are directly obtained from the synthesis as monoanionic salts, and the isostructural crystal structures of [nBu4N][Ni(α-mtpdt)2] and [nBu4N][Au(α-mtpdt)2] were solved by single-crystal X-ray diffraction. For M = Co, Pt and Pd, both monoanionic and dianionic salts were obtained, and the crystal structures of [Ph4As]2[Co(α-mtpdt)2] and [Ph4As]2[Pd(α-mtpdt)2] were determined by single-crystal X-ray diffraction. The Co compound presents a rare tetrahedral coordination geometry. The oxidation of the monoanionic Ni and Au complexes with iodine leads to stable neutral complexes, which are fairly soluble in common organic solvents such as acetonitrile and dichloromethane. The crystal structure of [Ni(α-mtpdt)2] was solved by single-crystal X-ray diffraction. The electrical conductivities of the neutral Ni and Au complexes as polycrystalline compressed pellets are typical of a semiconductor; the room-temperature conductivities are 5.2 × 10–7 and 8.7 × 10–5 S cm–1, and the activation energies are 325 and 287 meV, respectively.

A new pyridine-substituted dithiolene complex, PPh4[Au(4-pdddt)2] (3), was prepared and characterised. Cyclic voltammetry shows three redox processes corresponding to the interconversion between dianionic, monoanionic, neutral and cationic states, as often presented by this type of bis(dithiolene) complexes. However, the last oxidation process in this compound leads to a polymerised species obtained as an electrodeposited film. By potentiostatic electrodeposition, thin films of either the neutral gold complex, [Au(4-pdddt)2] (4), or the polymerised cationic species can be obtained. Both films absorb strongly in the NIR region and have properties consistent with the incorporation of the intact metal bis(dithiolene) complex. A mechanism for polymerisation through formation of S–S interligand bonds is proposed.

The study of the family of compounds α-(Per)2[M(mnt)2], (M = Cu, Au, Ni, Pd, Pt, Co, Fe) has started more than 30 years ago with the report of first members, but has been always limited by difficulties in the growth of high quality and large single crystals. These compounds can be obtained by oxidation of perylene in the presence of anion salts, either with iodine or electrochemically. The electrocrystallisation, which usually yields better quality crystals than the chemical oxidation route, has however several limitations and it is significantly more difficult to apply to these perylene compounds, which may present different stoichiometries and polymorphs, than to charge transfer salts of many other donors. These difficulties are associated with the low solubility of perylene and the instability of its radical cation in solution. The results of a systematic study to optimise the growth conditions of these compounds by electrocrystallisation and to identify key factors governing the formation of their different phases are presented. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A family of salts that was based on the [Ni(α-tpdt)x]n– anions (α-tpdt = 2,3-thiophenedithiolate) and the K+ crown-ether cations were prepared and were then structurally and magnetically characterised. In [K(18-crown-6)][Ni(α-tpdt)2], the anion has a square planar coordination geometry with ligand disorder and the cations and anions are segregated in alternating layers in the crystal structure, as was found in the previous [Ni(α-tpdt)2]– salts. Two salts were obtained with the [K(15-crown-5)2]+ cation. The expected 1:1 salt was obtained, which had the usual anion square planar coordination geometry for [Ni(α-tpdt)2]– but that had a new molecular arrangement based on an anion double chain. In addition, a 2:1 salt was obtained, which had a new anionic geometry, namely, [Ni4(α-tpdt)6]2–, which is an unprecedented example of an in-line mixed-valence Ni4 dithiolene (Ni4–S12) cluster. A compound with an eight-membered tetrasulfide ring, namely a bis(thiophene-2,3-diyl) bis(sulfide), was also obtained. The salts that are based on the paramagnetic [Ni(α-tpdt)2]– anion presented interesting magnetic properties that resulted from the competition between the antiferromagnetic (AFM) and ferromagnetic (FM) interactions with a low-temperature cluster glass behaviour, which was associated with the cis-trans ligand disorder.

The synthesis and characterisation of a group of vinylenedithio–TTFs bearing two or four 2- or 4-pyridyl groups are described, along with related nickel and gold bidithiolene, as potential substrates for preparing multifunctional materials. In spite of the pyridyl groups not being coplanar with the vinylenedithio–TTF cores and the significant chair-type distortions of the cores, because of the flexing of the dithiin rings, these substituted donors preserve the stacking ability of the unsub

The family of charge-transfer (CT) salts [M(Cp*)2][Ni(α-tpdt)2] [α-tpdt = 2,3-thiophenedithiolate; M = Fe (1), Mn (2), Cr (3)] were prepared. The crystal structure of 3 is similar to that previously reported for 1 and is composed of alternatinglayers each consisting of parallel mixed donor–acceptorD+A–D+A–D+A– chains, and the chains in adjacent layers are perpendicular. A similar crystal structure is expected to occur in 2. The McConnell I model was used to analyze the intermolecular magnetic coupling in this family of compounds. The predicted ferromagnetic (FM) intrachain coupling and the antiferromagnetic (AFM) coupling in the interchain coupling (both intra and interlayer) are in good agreement with the experimental results. The magnetic behavior of these compounds is dominated by FM interactions, which are ascribed to the intrachain FM DA interactions. The low-temperature magnetic behavior of the new CT salts contrasts that previously reported for metamagnetic compound 1. Whereas CT salt 3 remains paramagnetic down to 1.6 K, 2 shows magnetic behavior that is typical of a frustrated magnet and has a blocking temperature of ca. 4 K. For this compound, the magnetic frustration results from a degenerate ground state in the interlayer spin arrangements. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The tetra-substituted TTF-type donors 4,4′,5,5′-tetrakis(2-pyridylethylsulfanyl)tetrathiafulvalene (1) and 4,4′,5,5′-tetrakis(2-pyrazylethylsulfanyl)tetrathiafulvalene (2) were prepared and characterized. These donors show a redox behaviour that is comparable with similar unsubstituted TTF donors, with a small increase of the redox potentials due to the electron-withdrawing effect of the pyridine and pyrazine groups. Single crystal X-ray diffraction analyses show structures with a strong segregation of TTF and azo moieties. The pyridine-substituted donor 1 was used as a bridging ligand to prepare a dinuclear CoII-coordination complex [1Co2(hfac)4] (hfac = hexafluoroacetylacetonate) with redox properties identical to that of 1. This dinuclear complex presents an effective magnetic moment of ca. 8 μB, corresponding to nearly independent S = 3/2 spins with weak antiferromagnetic interactions below 65 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

The gold and nickel bisdithiolene complexes based on new highly extended ligands incorporating fused tetrathiafulvalene and thiophene moieties (alpha-tdt=thiophenetetrathiafulvalenedithiolate and dtdt=dihydro- thiophenetetrathiafulvalenedithiolate), were prepared and characterised by using cyclic voltammetry, single crystal X-ray diffraction, EPR, magnetic susceptibility and electrical transport measurements. These complexes, initially obtained under anaerobic conditions as diamagnetic gold monoanic [nBu(4)N][Au(alpha-tdt)(2)] (4), [nBu(4)N][Au(dtdt)(2)] (3) and nickel dianionic species [(nBu(4)N)(2)][Ni(alpha-tdt)(2)] (8), [(nBu(4)N)(2)][Ni(dtdt)(2)] (7), can be easily oxidised to the stable neutral state just by air or iodine exposure. The monoanionic complexes crystallise in at least two polymorphs, all of which have good cation and anion segregation in alternated layers, the anion layers making a dense 2D network of short SS contacts. All of the neutral complexes, obtained as microcrystalline or quasi amorphous fine powder, present relatively large magnetic susceptibilities that correspond to effective magnetic moments in the range 1-3 mu(B) indicative of high spin states and very high electrical conductivity that in case of the Ni compound can reach sigma(RT) approximately 250 S cm(-1) with a clear metallic behaviour. These compounds are new examples of the still rare single-component molecular metals.

Invited for the cover of this issue is the group of Manuel Almeida at the University of Lisbon. The cover image illustrates the unit cell of a layered dysprosium hydroxide material that is the first example of a layered lanthanide compound showing single-molecule-magnet behavior.

The preparation and characterisation of new thiophenedithiolate complexes of Cu, Co and Pt with the ligands α-tpdt and tpdt (α-tpdt = 2,3-thiophenedithiolate, tpdt = 3,4-thiophenedithiolate) is reported. The Co and Pt complexes present regular square-planar coordination geometry and low oxidation potentials when compared with complexes with simpler ligands, but their monoanionic state is found to be rather unstable. The Co(tpdt)2 complex can be isolated both in the monoanionic and dianionic states as a stable compound but the Co(α-tpdt)2 and the Pt complexes can be obtained only in the dianionic state, while their monoanionic state is unstable. The Co and Pt complexes can, however, be easily oxidised to the neutral state, giving a fine-powdered microcrystalline material without high electrical conductivity. With Cu only a less frequent geometry based on a tetrametallic CuI cluster and three ligands is observed as [Cu4(α-tpdt)3]2– and [Cu4(tpdt)3]2–. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Starting from the first organic spin ladder reported, a dithiophene-tetrathiafulvalene salt ((DT-TTF)2[Au(mnt)2]) (mnt = maleonitriledithiolate), two different approaches to enlarge the family of organic spin-ladder systems are described. The first approach consists of a molecular variation of the donor; to that purpose, the new TTF derivative ethylenethiothiophene-tetrathiafulvalene (ETT-TTF, 3), is synthesized and structurally characterized. From this donor a new ladder-like structure compound, (ETT-TTF)2[Au(mnt)2] (4), isostructural with (DT-TTF)2[Au(mnt)2], is obtained. However, the magnetic properties of 4 do not follow the known spin-ladder behavior owing to orientational disorder exhibited by the ETT-TTF molecules in the crystal structure. In the second approach, the acceptor complex is changed, either in the nature of the ligand or in the metal. With the [Au(i-mnt)2]– salt (i-mnt = iso-maleonitriledithiolate), the new ladder-like compound (DT-TTF)2[Au(i-mnt)2] (5), isostructural with 4, is obtained, but only as a minority product. Two other compounds with a different anion generated in situ, bearing a Au(I) dimeric core, were also isolated; (DT-TTF)9[Au2(i-mnt)2]2 (6) as the most abundant phase and (DT-TTF)2[Au2(i-mnt)2] (7) as another minority phase. Salt 7 is characterized by X-ray crystallography as a chiral compound, due to the torsion of the ligands around the central Au–Au bond. The magnetic properties of (DT-TTF)2[Au(i-mnt)2] (5) indicate that it follows a spin-ladder behavior and the electron paramagnetic resonance (EPR) data is fitted to the Troyer and Barnes and Riera equations with the parameters Δ/kB = 71 K, J∥/kB = 86 K, and J⟂/kB = 142 K, indicating a J⟂/J∥ ratio of 1.65. The change of the gold complex [Au(mnt)2] for its copper analogue, [Cu(mnt)2] also leads to a ladder-like structure, (DT-TTF)2[Cu(mnt)2] (8), which is isostructural with the gold analogue and with salts 4 and 5. The fully ionic salt (DT-TTF)[Cu(mnt)2] (9) is also obtained. The magnetic properties demonstrated that compound 8 is the third organic spin-ladder system of this family, and the values found by a fitting to the ladder equations were Δ/kB = 123 K, J∥/kB = 121 K, and J⟂/kB = 218 K, corresponding to a J⟂/J∥ ratio of 1.75, similar to that of 5 and close to that of an ideal spin ladder.

The synthesis, structure, and physical properties of the oxalate-based molecular magnets with the formula [ZII(bpy)3][ClO4][MIIFeIII(ox)3] (ZII = Fe, Ru; MII = Mn, Fe; bpy = 2,2'-bipyridine; ox = oxalate dianion) are presented here. All compounds are isostructural and crystallize in the chiral cubic space group P4132, and contain three-dimensional dimetallic networks formed by alternating MII and MIII ions that are connected by oxalate anions. These compounds exhibit strong antiferromagnetic interactions that give rise to magnetic ordering as ferrimagnets or weak ferromagnets, with critical temperatures of up to 20 K, which is twice as high as those found for the isostructural magnets based on CrIII, as determined by magnetic measurements and Mossbauer spectroscopy. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

A series of new M[(dcbdt)2]−z complexes of the dicyanobenzodithiolate (dcbdt) ligand with a range of transition metals (M = Co, Pd, Pt, Cu, Au and Zn) in different oxidation states (z = 0.4, 1, 2) were prepared as their nBu4N salts and characterised by X-ray diffraction, cyclic voltammetry, EPR and static magnetic susceptibility. Their properties are discussed in comparison with the Ni and Fe analogues described by us recently. The structures of these complexes belong to four distinct groups: i) the ZnII compound 10 is triclinic P with the metal in a tetrahedral coordination geometry; ii) other MII complexes [M = Pt (8), Pd (7), Co (3) and Cu (5)] are monoclinic C2/m, and are isostructural with the NiII analogue, presenting a perfectly planar square geometry; iii) the CoIII compound 4 is triclinic P , and isostructural with the Fe and Ni analogues, with a strong dimerisation of the M(dcbdt)2 units and the metal in a square-pyramidal coordination geometry; iv) the MIII salts with M = Au (2), Cu (6) and Pt (9) are monoclinic P21/c and the complexes are arranged as pseudo-dimers. The EPR and static magnetic-susceptibility measurements show that the CoII (3), CuII (5), PtIII (9) and CoIII (4) complexes are paramagnetic corresponding to an S = 1/2 state, except for CoIII, which is in a high-spin S = 1 configuration. The solid state EPR spectra of the CoII compound presents a hyperfine structure typical of the I = 7/2 59Co. The temperature dependence of the paramagnetic susceptibility of the PtIII compound follows a singlet-triplet model with a dimer antiferromagnetic coupling, J, of 984 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

With the aim of expanding the studies on 2D systems containing uranium, U/Co multilayers with layer thickness ranging from 50 to 200 A were recently prepared by dc magnetron sputtering onto glass. The multilayers were characterized by Grazing-Incidence X-Ray Diffraction (GIXRD) and Rutherford Backscattering Spectrometry (RBS). Magnetization measurements performed with a squid magnetometer showed that the multilayers have a ferromagnetic behaviour, with the magnetic signal increasing with the thickness of the layers. The analysis of magnetic anisotropy evidenced an easy magnetic direction in the film plane with large anisotropy fields, which increase with the thickness of the layers and suggests a positive contribution of surface anisotropy to the effective anisotropy K eff .

The copper bisdithiolene complexes based on highly extended ligands incorporating fused TTF and thiophene moieties (α-tdt = tiophenetetrathiafulvalenedithiolate and dtdt = dihydro-thiophenetetrathiafulvalenedithiolate), were prepared and characterised by cyclic voltammetry and electrical transport measurements. The anionic complexes, (nBu4N)x[Cu(dtdt)2] (1) and (nBu4N)x[Cu(α-tdt)2] (2), (1

The charge transfer salt based on the organic donor dithiophene-tetrathiafulvalene and palladium bis-maleonitrile-dithiolate, (DT-TTF)2[Pd(mnt)2], was obtained as single crystal by electrocrystallisation in dichloromethane. The crystal structure is different from the analogues previously described with other metals (Au, Cu, Ni and Pt) but of the same type as (TTDM–TTF)2[Au(mnt)2]. However in this DT-TTF salt the Pd complex is dianionic, being the donor molecules fully oxidised and the compound should then be formulated as (DT-TTF+)2[Pd(mnt)2]2–. This compound has properties of a quasi-one-dimensional semiconductor with sRT∼ 6 × 10–2 Scm–1 and Ea∼0.172 eV (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A new salt based on the [Ni(α-tpdt)2]- anion, (α-tpdt=2,3-thiophenedithiolate) and on the K+ crown-ether cation [K(18-crown-6)]+ is magnetically characterized. This salt exhibits interesting magnetic properties resulting from the spin polarization within the anionic molecule and from the specific molecular interactions arrangement in the crystal structure. Therefore the magnetic properties are due to the competition between AFM and FM interactions leading, at low temperature, to a cluster glass behaviour that is also associated with the ligand cis-trans disorder. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The conditions that allowed for the first time the growth of (Per)2[Pd(mnt)2] crystals by electrocrystallisation are described. The electrocrystallisation is limited by close proximity of the oxidation potentials of the perylene donor and [Pd(mnt)2]- anion. Depending on the experimental conditions different morphologies can be obtained. (Per)2[Pd(mnt)2] crystals were found to be mainly of the β-polymorph with properties comparable to the Cu, Ni and Pt previously described. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The ternary intermetallic magnetic compound UFe6Ge6 was studied by single crystal X-ray diffraction and 57Fe Mossbauer spectroscopy; the magnetic properties were also investigated. UFe6Ge6 was found to melt congruently at c. 950 °C and to crystallize in space group P6/mmm, with cell parameters a = 5.126 8(4) A , c = 4.050 7(5) A , V = 92.204 7(13) A 3 , Z = 0.5 and a YCo6Ge6 type structure that was solved by single crystal X-ray diffraction to a final R = 0.059 (Rw = 0.071). Magnetization measurements suggest two transitions: one at 322(5) K reminiscent of an antiferromagnetic ordering and another ferromagnetic at 230(10) K. According to 57Fe Mossbauer spectroscopy there is a transition at 322(5) K associated with the ordering of the Fe moments which do not undergo any noticeable reordering at lower temperatures. Thus the transition at 230 K is tentatively attributed to the ordering of the U-sublattice.

UFe10Mo2 was obtained as single-phase polycrystalline material by annealing at 1450 K a polyphasic sample prepared by melting the elements. This compound was characterized by single-crystal X-ray diffraction, 57Fe Mossbauer spectroscopy and magnetization measurements. UFe10Mo2 was found to crystallize in the space group I4/mmm with cell parameters a = 8.4859(3) A, c = 4.7508(2) A, V = 342.103(21) A3, Z = 2 and a ThMn12-type structure that was solved by single-crystal X-ray diffraction to a final R = 0.0345 (wR = 0.0372). The Mo atoms are randomly distributed in the 8i positions. Magnetization measurements show a ferromagnetic-like behaviour for T < 198 K and, in free powder, a saturation magnetization at low temperature of 8.8 μB per formula unit. Comparison with fixed powder measurements indicates a basal plane type of anisotropy. 57Fe Mossbauer spectra below Tc show a distribution of hyperfine fields from 0 to 20 T. This distribution was analysed considering the different local configurations around each Fe atom and assuming the Fe site distribution deduced from X-ray data.

The properties of the salts based on metallocenium cations and transition metal bisdichalcogenide anions are reviewed and particular attention is paid to the correlation between the magnetic properties correlated and the crystal and molecular structures. The large majority of these salts have crystal structures based on linear chain arrangements of alternating cation (D+) and anion (A−) stacks which are classified in four major structural types, depending on the stacking motifs. The magnetic properties of these salts, which at low temperatures can present a wide range of magnetic order type and phase transitions, are correlated with the type of magnetic interaction between the magnetic building blocks, which in the large majority of the cases can be well described by the McConnell model using spin density calculations.

The title compound, C 20 H 10 S, contains discrete molecules which are essentially planar and are regularly stacked along the b axis [interplanar separation 3.474 (4) A]; columns are bridged by short S...S interstack contacts of 3.506 (2) A about inversion centres.

YFe x Al 12− x alloys within their homogeneity range were synthesized by arc-melting. Their crystal structures were determined for the first time from single-crystal X-ray diffraction data: ThMn 12 -type structure, I4/mmm space group; a =0.87561(6), c =0.50446(5) nm for YFe 4 Al 8 , R =0.0295, wR 2=0.0451; a =0.87159(8), c =0.50324(9) nm for YFe 4.57 Al 7.43 , R =0.0386, wR 2=0.076; a =0.88226(8), c =0.50632(9) nm for YFe 3.08 Al 8.92 , R =0.0266, wR 2=0.0581. The compound YFe 3.08 Al 8.02 is reported for the first time.

The crystal structure of the binary boride NdB 4 , ( P4/mbm space group, a =7.1775(3) A, c =4.0996(2) A, Z =2, V =211.20(1) A 3 , ρ =4.070 g×cm −3 , μ =12.70 mm −1 , R =0.0378, wR2 =0.0945 for 371 reflections with F o >4 σ ( F o )), was determined from single crystal X-ray diffraction (diffractometer Enraf-Nonius CAD-4, Mo Kα-radiation). The compound was found to crystallize with the ThB 4 structure type.

Phase equilibria in the Ce–Au–Sb system were derived from X-ray diffraction data and, optionally, from scanning electron microscope analysis of annealed at 870 K alloys. The structures of compounds were investigated using X-ray single crystal and powder diffraction methods. Five ternary compounds were found to exist within the investigated concentration region (0–50 at.% Ce). New U3Cu2Sb3-type Ce3Au2Sb3 compound (a = 4.5966(4) A, c = 24.005(2) A, space group P63/mmc, no. 194) was discovered and studied by X-ray single crystal diffraction. The existence and crystal structures of following compounds were confirmed at 870 K: the ZrCuSi2-type CeAu1−xSb2, UHg2-type Ce(Au1−xSbx)2 and Y3Au3Sb4-type Ce3Au3Sb4. For the reported earlier UHg2-type Ce(Au1−xSbx)2 and ZrCuSi2-type CeAu1−xSb2 compounds the homogeneity regions were established from annealed at 870 K alloys: 0.19 ≤ x ≤ 0.28 and 0 ≤ x ≤ 0.21 respectively. At 870 K, the structure of CeAuSb compound was found to be related to the CaIn2-type from X-ray powder diffraction data. Moreover, the single crystal X-ray diffraction studies of the as-cast CeAu1−xSb2 for x = 0.118(2) and x = 0.162(4) are given in present paper as well.

A new ternary compound Ce(Au,Sb) 2 , with a homogeneity range has been observed from X-ray powder diffraction of as cast alloys, a = 4.743–4.712 A, c = 3.567–3.768 A. Its crystal structure was investigated by X-ray diffraction from Ce(Au 1− x Sb x ) 2 ( x = 0.266) single crystal: CAD-4 automatic diffractometer, Mo Kα radiation, a = 4.7256(6) A, c = 3.6711(6) A, P 6/ mmm space group, V = 70.997(17) A 3 , Z = 1, ρ = 10.732 Mg/m 3 , μ = 76.369 mm −1 , R 1 = 0.0415, w R 2 = 0.0793 for 99 reflections with I > 2 σ ( I 0 ). The coordination polyhedron of X (X = 0.734Au + 0.266Sb) atom is a full-capped trigonal prism [XCe 6 X 3 X 2 ]. Ce atom is coordinated by 14 atoms: [CeX 12 Ce 2 ]. The compound is isotypic with UHg 2 structure, a deformation derivative of AlB 2 structure type. It forms isostructural compounds with La and Pr.

The crystal structure of the ternary borides CeRh 3 B 2 , CeCo 3 B 2 structure type, P6/mmm space group, a =5.470(2) A, c =3.080(2) A, Z =1, V =79.81(2) A 3 , ρ =9.789 g cm −3 , μ =28.92 mm −1 and YIr 3 B 2 , ErIr 3 B 2 structure type, C2/m space group, a =5.432(2) A, b =9.398(4) A, c =3.099(1) A, β =90.38(1)°, Z =2, V =158.2(1) A 3 , ρ =14.425 g cm −3 , μ =143.632 mm −1 were refined to R =0.0224, wR 2 =0.0573 and R =0.0467, wR 2 =0.1138, respectively, from single crystal X-ray diffraction data of the “as cast” samples. The CeCo 3 B 2 stucture type was confirmed for the CeRh 3 B 2 compound, a =5.47509(16) A, c =3.08143(9) A from Rietveld refinement of X-ray powder diffraction data of the sample anealed at 1070 K ( R P =2.76%, R WP =4.32%, R B =4.91%, R F =4.94%). The crystal structures of the annealed at 1070 K RIr 3 B 2 (R=Ce, Nd and Y) and YRh 3 B 2 compounds are more complicated. Different splittings of the reflexions in the X-ray powder patterns of these compounds can be an indication of different structure models related with the CeCo 3 B 2 and ErIr 3 B 2 structure types.

The crystal structure of the CeIr 3 compound was refined for the first time from single-crystal X-ray diffraction data, down to R =0.0490, wR2=0.1052. This compound crystallizes in the PuNi 3 structure type, space group R 3 m ( a =5.290(2) A, c =26.220(4) A, Z =9, V =635.44 A 3 , ρ =16.835 g cm −3 , μ =156.36 mm −1 ). CeIr 3 belongs to the R 2 m + n M 4 m +5 n family, where m and n are the numbers of MgCu 2 - and CaCu 5 -type slabs, respectively. For CeIr 3 , m and n were found to be both equal to 1.

The crystal structure of a new ternary boride CePt2B, space group P6222 (N180), a=5.4898(5) A, c=7.8860(9) A, Z=3, V=205.83(1) A, ρ=13.097 g cm−3, μ=117.63 mm−1 was refined to R=0.0384, wR2=0.0926 from single-crystal X-ray diffraction data. Rietveld refinement of the X-ray powder data collected from the CePt2B sample annealed at 1070 K confirmed the structural model obtained by single-crystal refinement (a=5.4811(3) A, c=7.8830(2) A, RF=0.0497, RB=0.0668 from X-ray powder diffraction). This is the first representative of a new structure type of intermetallic compound. Preliminary magnetic measurements show the sample to be nonsuperconducting at 2 K with possible magnetic ordering below 7 K.

The cover picture shows the multilayer spin arrangement in [Mn(Cp*)2][Ni(α-tpdt)2] (α-tpdt = 2,3-thiophenedithiolate). The crystal structures of the salts [M(Cp*)2][Ni(α-tpdt)2] (M = Fe, Mn and Cr) consist of alternating layers that are composed of arrangements of parallel mixed chains. The chains in neighboring layers are perpendicular. The arrangement between the chains and the magnetic anisotropy of the cations in case of the salt [Mn(Cp*)2][Ni(α-tpdt)2] lead to a degenerate ground state and to a frustrated magnetic behavior, which can be associated with the absence of long-range order between the ferromagnetic layers. Details are discussed in the article by M. Almeida, V. Gama et al. on p. 5327 ff.