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Ferro-ferri-katophorite (IMA2016–008), ideally Na(NaCa)(Fe2+4Fe3+)(Si7Al)O22(OH)2, was found as xenocrysts up to 3 cm long and replacement rims around aegirine–augite in silicocarbonatite dykes cropping out in the Sierra de Maz, La Rioja province, NW Argentina. Ferro-ferri-katophorite is black and has vitreous lustre and a pale green streak. The new mineral is brittle, with perfect {110} cleavage and has a Mohs hardness of 6. The measured density is 3.32(1) g/cm3. In plane-polarised light it is strongly pleochroic, X = light greenish brown, Y = dark greyish brown and Z = dark greyish olive green. Absorption (very strong) is Z > Y > X. The orientation is: Z ∥ b , and X forms a small angle with [001]. Ferro-ferri-katophorite is biaxial (–), with α = 1.688(3), β = 1.697(3), γ = 1.698(3) and 2V(calc) = 36.7°. It is monoclinic, space group C 2/ m , a = 9.8270(7), b = 18.0300(8), c = 5.316(4) Å, β = 104.626(4)°, V = 911.4(6) Å3 and Z = 2. The strongest five lines in the powder X-ray diffraction pattern [ d in Å (I)(hkl)] are: 8.416(100)(110), 3.135(50)(310), 2.815(26)(330), 2.720(18)(151) and 1.4422(15)($\bar{6}$ 61). The chemical composition is SiO2 43.08, TiO2 2.76, ZrO2 0.15, Al2O3 8.76, V2O3 0.07, Fe2O3 9.28, FeO 13.85, MnO 0.43, MgO 6.88, CaO 6.58, ZnO 0.06, Na2O 5.55, K2O 1.18, Cl 0.01, H2O calc 1.36, total 99.95 wt.%. The formula unit (confirmed by single-crystal structural analysis) is (Na0.74K0.23)Σ0.97(Ca1.08Na0.91Mn0.01)Σ2.00(Fe2+1.78Mg1.57Fe3+1.07Ti4+0.32Al0.19Mn2+0.04Zr0.01V3+0.01Zn0.01)Σ5.00(Si6.61Al1.39)Σ8.00O22(OH1.59O0.61)Σ2.00. Aluminium is strongly ordered at the T (1) site. Ferro-ferri-katophorite is the 9th species carrying the katophorite root name and is related to katophorite by the Fe2+ + Fe3+ → Mg2+ + Al3+ substitution. Type material was deposited at the Museo de Mineralogía "Stelzner", Universidad Nacional de Córdoba, Argentina, under catalogue number MS003341. [ABSTRACT FROM AUTHOR]

Owing to the importance of the single‐wavelength anomalous diffraction (SAD) technique, the recently developed |ρ|‐based phasing algorithm (SM,|ρ|) incorporating the inner‐pixel preservation (ipp) procedure [Rius & Torrelles (2021). Acta Cryst A77, 339–347] has been adapted to the determination of anomalous scattering substructures and its applicability tested on a series of 12 representative experimental data sets, mostly retrieved from the Protein Data Bank. To give an idea of the suitability of the data sets, the main indicators measuring their quality are also given. The dominant anomalous scatterers are either SeMet or S atoms, or metals/clusters incorporated by soaking. The resulting SAD‐adapted algorithm solves the substructures of the test protein crystals quite efficiently. [ABSTRACT FROM AUTHOR]

The incorporation of the new peakness‐enhancing fast Fourier transform compatible ipp procedure (ipp = inner‐pixel preservation) into the recently published SM algorithm based on |ρ| [Rius (2020). Acta Cryst A76, 489–493] improves its phasing efficiency for larger crystal structures with atomic resolution data. Its effectiveness is clearly demonstrated via a collection of test crystal structures (taken from the Protein Data Bank) either starting from random phase values or by using the randomly shifted modulus function (a Patterson‐type synthesis) as initial ρ estimate. It has been found that in the presence of medium scatterers (e.g. S or Cl atoms) crystal structures with 1500 × c atoms in the unit cell (c = number of centerings) can be routinely solved. In the presence of strong scatterers like Fe, Cu or Zn atoms this number increases to around 5000 × c atoms. The implementation of this strengthened SM algorithm is simple, since it only includes a few easy‐to‐adjust parameters. [ABSTRACT FROM AUTHOR]

The origin‐free modulus sum function SM refines the set Φ of phases of the structure factors by maximizing the coincidence between the experimental origin‐free modulus function and the calculated one in terms of the ρ(Φ)2 density function [Rius, J. (1993). Acta Cryst. A49, 406–409]. Maximization is normally achieved through the recursive application of a Fourier‐based algorithm. The purpose of the present study is: (i) to show that ρ(Φ)2 can be replaced by |ρ(Φ)| in SM; (ii) to illustrate the viability of the corresponding phasing algorithm with experimental data. [ABSTRACT FROM AUTHOR]

Games and toys must be treated from different points of view if we want to get a global idea of their importance. For all this, it's necessary to analyze different characters that have treated the different playful themes, whether from the sociological, anthropological, cultural, sports, philosophical, poetic field... The proposal is framed in the philosophical, historical and personal treatment that Walter Benjamin did related to this theme. The object of study is this appearance of the game and the toy in the thinking of the German philosopher, whether from his travels, as from his interpretations, which often criticize the society of the time. Methodology used has been based on the analysis of its main texts. These primary sources are reinforced by a set of contributions that contextualize Benjamin's speech. Results allow us to verify the importance that Benjamin gave to these elements -game and toy- and their evolution. A set of actions are proposed that bring back the original meaning of the action of playing and detach from the scourge of consumerism. The thought of the German philosopher can therefore become a foothold, of recovering historical memory and in favor of an education of the game, of the toy -- and of course, of sport -- critical and real. [ABSTRACT FROM AUTHOR]

Agonistic games are one of the most emblematic social and cultural manifestations of human civilization. Prisoner's bar, is one of these games. Subtracting from this ancestral game, a playful pedagogical genealogy in the exercise of power as a strategy to discipline the body is the objective of the study of this article. A genealogical methodology and an approach from critical theory allows us to review, how the game of the prisoner's bar (or base) has aroused the approval of educators and learners for several centuries, accepted with the object of an unspeakable disciplinary domination over bodies. Analyzing the results, prisoner's bar underlies the first strategy game of civilization. It is conceived, as well as the point of origin from which started other collaboration-opposition games that have transformed into sports. In conclusion, this study must be able to transfer to the present and favor a new ludic and critical pedagogy. [ABSTRACT FROM AUTHOR]

The d2Dplot computer program provides a set of tools for the visualization, processing and analysis of 2D X‐ray diffraction (2DXRD) data. Among the operations available there are the sum/subtraction of 2DXRD images, conversion to 1D data (powder pattern), azimuthal plotting, calibration of instrumental parameters, background subtraction and a command‐line mode to run operations inside data processing pipelines. The graphical user interface allows easy use of the program. It also includes two main features: (i) the possibility of creating a user compound database to help in the fast phase identification of similar samples, and (ii) a detailed peak analysis routine for the application of the through‐the‐substrate microdiffraction methodology. d2Dplot is a computer program for the visualization and processing of 2D X‐ray diffraction data including a user‐created compound database and a peak analysis routine for the application of the through‐the‐substrate microdiffraction methodology. [ABSTRACT FROM AUTHOR]

The genealogy of physical education and modern sport has a civilizing and pedagogical foundation. This was forged through the disciplinary codes of Catholic morality that used the classic aphorism: Mens sana in corpora sano. In Spain, Counter-Reformation used education with the purpose of building a solid Catholic state. Methodologies used, characterized by the sense of eutrapelia and emulation, were devices that acted in the modeling of corporal docility and the Christian gentleman. In this way, different social uses of corporality appeared, both in education, as in military training, recreation and people‘s work and their religious life. From this an ethical and bourgeois conception arose that, through play, emulation and eutrapelia, based the foundations of a capitalism and a new way of imagining the world. The analysis of this conception and sense of corporality in the Counter Reformation (XVI and XVII centuries) is the object of study in this work. The methodology has been based on the analysis of the main primary sources, which have been contextualized with subsequent works that contribute to create a certain hermeneutic vision to the study. It’s concluded that education of body at this time was an excuse to promote a national, patriotic and servile ideal to the Spanish homeland. [ABSTRACT FROM AUTHOR]

Successful phasing of synchrotron through-the-substrate microdiffraction data by δ-recycling direct-methods largely depends on the number of missing intensities caused by the limited sample rotation range [J. Rius, Direct phasing from Patterson syntheses by δ recycling. Acta Cryst. A 2012, 68, 77-81]. Particularly, for the unfavorable triclinic system, dataset completeness resulting from a single series of consecutive φ-scans covering a total φ interval of ±35° is around 41%. This value is not enough for the routinary solution of a crystal structure by δ-recycling but can be increased by ~29% by applying the orthogonal χ strategy consisting of merging the information of two series of orthogonal φ-scans collected at the same microvolume of the polished thin section. Test calculations using simulated and experimental tts-data of the triclinic mineral axinite confirm that, with the help of the orthogonal χ strategy, crystal structures can be solved routinely. Since data in the ±35 φ-interval are normally accessible even for relatively thick glass-substrates (1-1.5 mm), a crystal structure can be determined from a single microvolume. For high-symmetry phases, due to the Laue symmetry redundancy, a single series of φ-scans normally suffices for the application of δ-recycling. However, when for experimental causes this series is incomplete, the orthogonal χ strategy also provides a simple way to increase the completeness which besides allowing solving the structure, is also beneficial for the subsequent refinement. [ABSTRACT FROM AUTHOR]

Ag2Cu3Cr2O8(OH)4, a new Ag–Cu–Cr–O layered mixed oxide, prepared by soft hydrothermal heterogeneous reactions, is reported. The new phase is an oxyhydroxide and presents a structure with alternating brucite-like Cu–O and Ag–O layers connected by individual chromate groups. The crystallographic structure has been solved and refined from high resolution powder X-ray diffraction data and is supported by density functional theory calculations, yielding a triclinic, space group P1̅, a = 5.3329(1) Å, b = 5.3871(1) Å, c = 10.0735(1) Å, α = 80.476(1)°, β = 87.020(1)°, γ = 62.383(1)°. Bond valence sums suggest the formulation of Ag+2Cu2+3Cr6+2O8(OH)4, an electronic state fully supported by X-ray photoelectron spectroscopy (XPS) and Cr K-edge X-ray absorption near edge structure (XANES) measurements. Ag2Cu3Cr2O8(OH)4 exhibits bidimensional Cu–O–Cu ferromagnetic correlations that are apparent at much higher temperatures than in other similar Cu–O layered structures, without coupling between Cu–O layers, which represents a unique case in the recent family of silver copper oxides. The role of Ag inducing bidimensionality in copper oxides is therefore expanded further with the presence of chromate anions. Ab initio calculations using density functional theory show that the electronic states involved originate mainly from Cu and OH orbitals, with minor contributions from Cr and the O atoms linking the Cr tetrahedra to the brucitic Cu–O layer, and almost no contribution from Ag. Further modeling of the in-plane magnetic interactions between Cu atoms suggests that the coupled magnetized stripes are responsible for the observed behavior. The results are discussed in relation with previous Ag–Cu mixed oxide phases where metallic behavior or ferro–antiferro transitions had been observed. The structure of this new Ag–Cu–O phase as compared with previous silver copper oxides supports the conclusion that the Ag–Cu layered ordering is favored under oxidizing conditions. [ABSTRACT FROM AUTHOR]

The work presents a description and analysis of chess books in Spain in the period 1900 to 1939. The tools used have been the main database of the Spanish libraries, along with bibliographical indexes of the subject matter. This has been contextualized with secondary sources. This allows us to locate the works analyzed in the social context of the time. Subsequently, a bibliometric statistical analysis used to assess and interpret issues of authorship, place of publication, publishers, years of increased circulation of works or controlling specific contents of the contributions. The results are useful to check that Barcelona and Madrid topped the printing of books. Also it manifests high Spanish and foreign production around the year 30. Other data is remarkable the informative function that had the most publications. [ABSTRACT FROM AUTHOR]

δ Recycling is a simple procedure for directly extracting phase information from Patterson-type functions [Rius (2012). Acta Cryst. A 68, 399-400]. This new phasing method has a clear theoretical basis and was developed with ideal single-crystal X-ray diffraction data. On the other hand, introduction of the automated diffraction tomography (ADT) technique has represented a significant advance in electron diffraction data collection [Kolb et al. (2007). Ultramicroscopy, 107, 507-513]. When combined with precession electron diffraction, it delivers quasi-kinematical intensity data even for complex inorganic compounds, so that single-crystal diffraction data of nanometric volumes are now available for structure determination by direct methods. To check the tolerance of δ recycling to missing data-collection corrections and to deviations from kinematical behaviour of ADT intensities, δ recycling has been applied to differently shaped nanocrystals of various inorganic materials. The results confirm that it can phase ADT data very efficiently. In some cases even more complete structure models than those derived from conventional direct methods and least-squares refinement have been found. During this study it has been demonstrated that the Wilson-plot scaling procedure is largely insensitive to sample thickness variations and missing absorption corrections affecting electron ADT intensities. [ABSTRACT FROM AUTHOR]

TALP is a new direct-space strategy for ab initio crystal structure determination of molecular crystals from powder diffraction data. The strategy is based on a preliminary exploration stage, which considers atomic overlap, followed by a subsequent stage of local incremental scans, both coupled to fast restrained least-squares minimizations with the atomic coordinates as refined parameters. The observed intensities are extracted from the powder pattern by a three-step procedure [Vallcorba, Rius, Frontera, Peral & Miravitlles (2012). J. Appl. Cryst. 45, 844-848], and the molecular model and distance restraints are derived from molecular mechanics calculations or from similar reported structures. The solution process consists of several independent trials, each one resulting in a crystal structure proposal with an associated figure of merit. TALP has been tested on laboratory X-ray powder diffraction data of 14 molecular compounds of known crystal structure and of variable complexity. In most cases, the crystal structure is solved in a short time (less than an hour), even for calculated models. For the most complex structures ( e.g. 13 torsion angles), the general scan is assisted by a rotation function, which provides a ranked list of most probable model orientations. In this way only the positional and conformation parameters need to be explored. [ABSTRACT FROM AUTHOR]

DAJUST is the generic name of a software package for powder diffraction formed by the core programs AJUST and SGAID (both written in Fortran) controlled by an easy-to-use Java user interface ( DAJUST_UI). While AJUST performs whole-pattern matching (cell-parameter refinement, profile fitting and intensity extraction), SGAID provides a list of the most probable space groups. For the extraction of the integrated intensities, AJUST uses the Le Bail procedure but with a different formula for refining the integrated intensities. Laboratory, synchrotron X-ray and neutron sources, and both reflection and transmission experimental geometries, are supported. Other program options include automated background estimation, asymmetry correction, and corrections for absorption, variable divergence and/or illumination. The extracted intensity data are written in text format and can be directly processed by the direct methods program XLENS [Rius (2011). Acta Cryst. A 67, 63-67] and the multisolution direct-space structure determination program TALP [Vallcorba, Rius, Frontera & Miravitlles (2011). Acta Cryst. A 67, C272]. [ABSTRACT FROM AUTHOR]

The direct methods origin-free modulus sum function [Rius (1993). Acta Cryst. A 49, 406-409] includes in its definition the structure factor G(Φ) of the squared crystal structure expressed in terms of Φ, the set of ϕ phases of the normalized structure factors E's of the crystal structure of unit-cell volume V. Here the simpler sum function variant = ∑ H E− H∫ VδP,Δ(Φ)exp( i2π Hr)d V extended over all H reflections is introduced which involves no G's and in which the δP,Δ function corresponds to δP = FT−1{()exp[ iϕ H(Φ)]} (where FT = Fourier transform) with all values smaller than Δ = 2.5σP equated to zero ( is the variance of δP calculable from the experimental intensities). The new phase estimates are obtained by Fourier transforming δP,Δ. This iterative phasing method (δ recycling) only requires calculation of Fourier transforms at two stages. Since δM≃δP/2, similar arguments are valid for δM = FT−1[( E H−〈 E〉)exp( iϕ H)] from which the corresponding phasing function follows. [ABSTRACT FROM AUTHOR]

Some theoretical and practical aspects of the application of transmission microdiffraction (µXRD) to thin sections (≤30 µm thickness) of samples fixed or deposited on substrates are discussed. The principal characteristic of this technique is that the analysed micro-sized region of the thin section is illuminated through the substrate (tts-µXRD). Fields that can benefit from this are mineralogy, petrology and materials sciences since they often require in situ lateral studies to follow the evolution of crystalline phases or to determine new crystal structures in the case of phase transitions. The capability of tts-µXRD for performing structural studies with synchrotron radiation is shown by two examples. The first example is a test case in which tts-µXRD intensity data of pure aerinite are processed using Patterson-function direct methods to directly solve the crystal structure. In the second example, tts-µXRD is used to study the transformation of laumonite into a new aluminosilicate for which a crystal structure model is proposed. [ABSTRACT FROM AUTHOR]

The article discusses the study on the use of Patterson-function direct methods (DM) in determining the structure of organic compounds from powder diffraction data. It says that the method is based on the structure factors (Φ) maximization of the sum function of Sp. It cites the optimization of Sp sum with Patterson-function tangent formula (TF) by the Sliding-Fast Fourier Transform (S-FFT) algorithm. It shows that Patterson-function DM can deal with powder data.

In order to extend the application field of the direct-methods S-FFT phase-refinement algorithm to density functions with positive and negative peaks, the equal-sign constraint was removed from its definition by combining ρ² with an appropriate density function mask [Rius & Frontera (2008). Acta Cryst. A64, 670-674]. This generalized algorithm (S2-FFT) was shown to be highly effective for crystal structures with at least one moderate scatterer in the unit cell but less effective when applied to structures with only light scatterers. To increase the success rate in this second case, the mask has been improved and the convergence rate of S2-FFT has been investigated. Finally, a closely related but simpler phase-refinement function (Sm) combining p (instead of ρ²) with a new mask is introduced. For simple cases at least this can also treat density peaks in the absence of the equal-sign constraint. [ABSTRACT FROM AUTHOR]

Many ocular pathologies, including retinopathy of prematurity (ROP), diabetic retinopathy, and age-related macular degeneration, result in vision loss because of aberrant neoangiogenesis. A common feature of these conditions is the presence of hypoxic areas and overexpression of the proangiogenic vascular endothelial growth factor (VEGF). The prevailing current treatment, laser ablation of the retina, is destructive and only partially effective. Preventive and less destructive therapies are much more desirable. Here, we show that mice lacking c-Jun N-terminal kinase 1 (JNK1) exhibit reduced pathological angiogenesis and lower levels of retinal VEGF production in a murine model of ROP. We found that hypoxia induces JNK activation and regulates VEGF expression by enhancing the binding of phospho-c-Jun to the VEGF promoter. Intravitreal injection of a specific JNK inhibitor decreases retinal VEGF expression and reduces pathological retinal neovascularization without obvious side effects. These results strongly suggest that JNK1 plays a key role in retinal neoangiogenesis and that it represents a new pharmacological target for treatment of diseases where excessive neoangiogenesis is the underlying pathology. [ABSTRACT FROM AUTHOR]

The hypoxic response is an ancient stress response triggered by low ambient oxygen (O2) (ref. 1) and controlled by hypoxia-inducible transcription factor-1 (HIF-1), whose α subunit is rapidly degraded under normoxia but stabilized when O2-dependent prolyl hydroxylases (PHDs) that target its O2-dependent degradation domain are inhibited. Thus, the amount of HIF-1α, which controls genes involved in energy metabolism and angiogenesis, is regulated post-translationally. Another ancient stress response is the innate immune response, regulated by several transcription factors, among which NF-κB plays a central role. NF-κB activation is controlled by IκB kinases (IKK), mainly IKK-β, needed for phosphorylation-induced degradation of IκB inhibitors in response to infection and inflammation. IKK-β is modestly activated in hypoxic cell cultures when PHDs that attenuate its activation are inhibited. However, defining the relationship between NF-κB and HIF-1α has proven elusive. Using in vitro systems, it was reported that HIF-1α activates NF-κB, that NF-κB controls HIF-1α transcription and that HIF-1α activation may be concurrent with inhibition of NF-κB. Here we show, with the use of mice lacking IKK-β in different cell types, that NF-κB is a critical transcriptional activator of HIF-1α and that basal NF-κB activity is required for HIF-1α protein accumulation under hypoxia in cultured cells and in the liver and brain of hypoxic animals. IKK-β deficiency results in defective induction of HIF-1α target genes including vascular endothelial growth factor. IKK-β is also essential for HIF-1α accumulation in macrophages experiencing a bacterial infection. Hence, IKK-β is an important physiological contributor to the hypoxic response, linking it to innate immunity and inflammation. [ABSTRACT FROM AUTHOR]

Since its discovery, the direct-methods origin-free modulus sum function S, originally denoted ZR by Rius [ Acta Cryst. (1993), A 49, 406–409], has been used for solving some relatively complex crystal structures from powder X-ray diffraction data. In these applications, phase refinement was normally carried out by maximizing the function S with a modified tangent formula. However, further progress in the powder diffraction field was hampered by the complexity of combining the tangent formula refinement that makes explicit use of triple-phase sums, with the introduction of constraints in real space necessary to counterbalance the information loss produced by peak overlap in powder diffraction. Recently, a considerably simpler and completely general phasing procedure (S-FFT) has been developed that maximizes S by means of the FFT algorithm and considers the triple-phase sums implicitly [Rius, Crespi & Torrelles (2007), Acta Cryst. A 63, 131–134]. As pointed out by the authors, this procedure could represent a source of progress in powder diffraction. Here, an algorithm combining the S-FFT procedure with real-space constraints according to the Shake-and-Bake philosophy [Weeks, de Titta, Miller & Hauptman (1993), Acta Cryst. D 49, 179–181] is given and its capability to treat powder diffraction data is proved with some realistic test structures. [ABSTRACT FROM AUTHOR]

An alternative way of refining phases with the origin-free modulus sum function S is shown that, instead of applying the tangent formula in sequential mode [Rius (1993). Acta Cryst. A 49, 406–409], applies it in parallel mode with the help of the fast Fourier transform (FFT) algorithm. The test calculations performed on intensity data of small crystal structures at atomic resolution prove the convergence and hence the viability of the procedure. This new procedure called S-FFT is valid for all space groups and especially competitive for low-symmetry ones. It works well when the charge-density peaks in the crystal structure have the same sign, i.e. either positive or negative. [ABSTRACT FROM AUTHOR]

The maximum-likelihood method is applied to direct methods to derive a more general probability density function of the triple-phase sums which is capable of predicting negative values. This study also proves that maximization of the origin-free modulus sum function S yields, within the limitations imposed by the assumed approximations, the maximum-likelihood estimates of the phases. It thus represents the formal theoretical justification of the S function that was initially derived from Patterson-function arguments [Rius (1993). ]. [ABSTRACT FROM AUTHOR]

Abstract: Neuron-derived orphan receptor-1 (NOR-1) is a transcription factor over-expressed in human atherosclerotic plaques that is involved in vascular smooth muscle cell proliferation. The aim of this study was to analyze whether NOR-1 plays a role in vascular endothelial growth factor (VEGF) induced endothelial cell growth. VEGF induced an early and transient up-regulation of NOR-1 in human umbilical vein endothelial cells (HUVEC). NOR-1 up-regulation by VEGF is processed through VEGF receptor-2 (VEGFR-2) and involves different signaling pathways including increase in cytosolic Ca2+, activation of protein kinase C and mitogen-activated protein kinase (MAPK) pathways (both extracellular-signaling regulated kinase [ERK] and p38 MAPK). VEGF induced CREB activation (phosphorylation in Ser133). In transfection assays, a dominant-negative of CREB inhibited NOR-1 promoter activity, while mutation of the three CRE sites in the NOR-1 promoter abolished VEGF-induced NOR-1 promoter activity. Antisense oligonucleotides against NOR-1 inhibited VEGF-induced endothelial cell growth (reduced DNA synthesis, and inhibited cell cycle progression and endothelial cell wound repair after mechanical injury). These results indicate that NOR-1 could be a key transcription factor regulating endothelial cell growth induced by VEGF. [Copyright &y& Elsevier]

Abstract: The reaction of the ZnCl2 with 6-methyl-2-pyridinecarboxylic acid, with a 1:2 metal-to-ligand molar ratio, affords optimum yields for the synthesis of [MeC5H4NCOOH][ZnCl3(H2O)]·[MeC5H4NCOO]H2O. The new complex has been characterised by elemental analyses, IR, 1H and 13C{1H} NMR, and single crystal X-ray diffraction methods. The X-ray structure analysis revealed that this structure consists of [ZnCl3(H2O)]− anions, [MeC5H4NCOOH]+ cations, [MeC5H4NCOO] zwitterions, and solvent molecules (H2O) by means of hydrogen bonds. [Copyright &y& Elsevier]

Part VIII. Focuses on the application of the direct-methods modulus sum function to the solution of crystal structures. Optimization algorithms; Phase-refinement function.

Obituary. [ABSTRACT FROM AUTHOR]

This paper provides a detailed technological characterization of the Roman opus sectile glasses (second century AD) coming from the renowned Gorga collection. Nine glass samples corresponding to imitations of the porfido verde antico, cipollino rosso, rosso antico, giallo antico, diaspro nero e giallo, semesanto and agate/alabaster stones were studied. The aim of this study was twofold: (i) archaeometric, i.e., to provide valuable data on the production, raw materials and techniques of these refined Roman glasses that mimic precious stones and (ii) methodological, i.e., to highlight the good performance of combining polished thin sections and local probe measurements for the study of glassy microstructures. Based on the nature of the flux used, the glasses from the samples were classified as either natron-type or mixed-type (natron/plant ash). The latter stem from remelted glasses and contain relict grains of wollastonite that were not found in the pure natron samples. Relict wollastonite crystals appear to be a proficient petrographic marker to spot recycled glasses along with the commonly used chemical fingerprints. Different production and colouring techniques were identified, even for a given type of imitated stone. Metallic Cu, Ca antimonates and Pb-Fe antimonates were the three opacifiers used for the opaque glasses. Based on the crystal morphologies, metallic Cu and Ca antimoniates were possibly synthesized in situ simultaneously with the glass, whilst the Pb-Fe antimonates were prepared ex situ. The working temperatures for these glasses were estimated within the 900–1100 °C range based on the presence and known thermal stability of some identified crystal phases. [ABSTRACT FROM AUTHOR]

Two phasing equations based on the Fourier syntheses δP = T−1[( E2−〈 E2〉)exp( iϕ)] and δM = T−1[( E−〈 E〉)exp( iϕ)] were recently described [Rius (2012). Acta Cryst. A 68, 77-81] ( E is the quasi-normalized structure factor and 〈 E〉 is the average over all reflections). These equations were found by comparison with the direct methods origin-free modulus sum function and constitute the core of the `δ recycling' phasing procedure. The derivation of these phasing equations from the minimization of a residual ( RP) between two differently calculated density functions (one of them including the positivity constraint) is shown. [ABSTRACT FROM AUTHOR]

We report about three bismuth sulfates from mineralized quartz dikes from Alfenza (Crodo, Italy), two new phases and a rare mineral, cannonite, all growing on bismuthinite. The first new phase occurs as white, "hortensia-like" aggregates of pseudo-hexagonal platelets, with perfect basal cleavage, ~20 µm wide and few micrometers thick. The approximate composition is Bi2O2(SO4), and cell parameters and symmetry, as determined by automatic diffraction tomography, are a = 22.0(4), b = 16.7(3), c = 15.9(3) Å, β = 102.9(5)°, space group Pc or P2/c. A major stacking disorder is detected by HR-SEM images and electron diffraction data. The second new phase was detected only by TEM. It can be distinguished by its random orientation on the TEM grid (i.e., absence of preferential parting), the higher resistance under the electron beam, and different cell parameters and structure, whereas the composition is similar (Bi/S ~ 2.2/1), apart for the presence of tellurium up to ~6 cations percents. The unit cell is hexagonal, space group ..., a = 9.5(2) and c = 15.4(3) Å. In this case, a structure model was obtained ab initio from electron diffraction data. Interestingly, the mineral has a porous structure with one dimensional porosity (diameter of the channel ~7 Å). Finally, within the same centimeter sized hand-specimens, we detected also cannonite. Its identification was done by automatic diffraction tomography. The measured cell parameters are a = 7.7(2), b = 13.9(3), c = 5.7(1) Å, β = 109.8(5)°, the space group P21/c. Cannonite at Alfenza forms radiating, acicular aggregates of colorless, transparent crystals with "scalpel-like" habit, elongated along c, up to 200 µm in length. [ABSTRACT FROM AUTHOR]

Abstract: Calcium diglyceroxide has been reported as a very active phase in the transesterification of triglycerides with methanol for biodiesel production. This work reports on the determination of the crystal structure of Ca diglyceroxide by Patterson-based direct methods from synchrotron X-ray powder diffraction (XRD) data in combination with characterisation by Differential Thermal Analysis-Thermogravimetry (DTA-TG), Scanning Electron Microscopy (SEM) and X-ray Photoelectron and Fourier Transform-Infrared spectroscopies (XPS and FT-IR). Its crystal structure is formed by molecular tetramers held together by a complex H-bond network. Both the XRD structural determination and the O1s XPS core level indicate the presence of a basic non-protonated O− anion at the surface of Ca diglyceroxide. Along with the presence of surface lipophilic CHx units, this O− anion may be the origin of this molecule’s high activity relative to CaO. [Copyright &y& Elsevier]

A new three-dimensional hydroxide-arsenate compound called compound 2 has been synthesized by heating (in air) of the sarkinite phase, Mn2(OH)AsO4 (compound 1), with temperature and time control. The crystal structure of this high-temperature compound has been solved by Patterson-function direct methods. A relevant feature of this new material is that it is actually the first member of the adamite-type family with mixed-valence manganese(II,III) and electronic conductivity. Crystal data: a = 6.7367(5) Å, b = 7.5220(6) Å, c = 9.8117(6) Å, α = 92.410(4)°, β = 109.840(4)°, γ = 115.946(4)°, P1. The unit cell content derived from Rietveld refinement is Mn8(O4Hx)(AsO4)4. Its framework, projected along [111], is characterized by rings of eight Mn atoms with the OH-/O2- inside the rings. These rings form an almost perfect hexagonal arrangement with the AsO4 groups placed in between. Bond-valence analysis indicates both partial deprotonation (x⩾ 3) and the presence of Mn in two different oxidation states (II and III), which is consistent with the electronic conductivity above 300 °C from electrochemical measurements. The electron paramagnetic resonance spectra of compound 1 and of its high-temperature form compound 2 show the presence of antiferromagnetic interactions with stronger magnetic coupling for the high-temperature phase. Magnetization measurements of room-temperature compound 1 show a complex magnetic behavior, with a three-dimensional antiferromagnetic ordering and magnetic anomalies at low temperatures, whereas for compound 2, an ordered state is not reached. Magnetostructural correlations indicate that superexchange interactions via oxygen are present in both compounds. The values of the magnetic exchange pathways [Mn-O-Mn] are characteristic of antiferromagnetic couplings. Notwithstanding, the existence of competition between different magnetic interactions through superexchange pathways can cause the complex magnetic behavior of compound 1. The loss of three-dimensional magnetic ordering by heating of compound 1 could well be based on the presence of Mn3+ ions (d4) in compound 2. [ABSTRACT FROM AUTHOR]

Hypoxia induces apoptosis but also triggers adaptive mechanisms to ensure cell survival. Here we show that the prosurvival effects of hypoxia-inducible factor 1 (HIF-1) in endothelial cells are mediated by neuron-derived orphan receptor 1 (NOR-1). The overexpression of NOR-1 decreased the rate of endothelial cells undergoing apoptosis in cultures exposed to hypoxia, while the inhibition of NOR-1 increased cell apoptosis. Hypoxia upregulated NOR-1 mRNA levels in a time- and dose-dependent manner. Blocking antibodies against VEGF or SU5614 (a VEGF receptor 2 inhibitor) did not prevent hypoxia-induced NOR-1 expression, suggesting that NOR-1 is not induced by the autocrine secretion of VEGF in response to hypoxia. The reduction of HIF-1α protein levels by small interfering RNAs, or by inhibitors of the phosphatidylinositol-3 kinase (PI3K)/Akt pathway or mTOR, significantly counteracted hypoxia-induced NOR-1 upregulation. Intracellular Ca2+ was involved in hypoxia-induced PI3K/Akt activation and in the downstream NOR-1 upregulation. A hypoxia response element mediated the transcriptional activation of NOR-1 induced by hypoxia as we show by transient transfection and chromatin immunoprecipitation assays. Finally, the attenuation of NOR-1 expression reduced both basal and hypoxia-induced cIAP2 (cellular inhibitor of apoptosis protein 2) mRNA levels, while NOR-1 overexpression upregulated cIAP2. Therefore, NOR-1 is a downstream effector of HIF-1 signaling involved in the survival response of endothelial cells to hypoxia. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Our aim was to investigate whether neuron-derived orphan receptor-1 (NOR-1), an early gene induced by low density lipoproteins (LDL) in vascular smooth muscle cells (VSMC), is regulated by statins. Methods: NOR-1 expression was analyzed in human VSMC in culture and in vivo in the aorta of diet-induced hyperlipemic pigs by RT-PCR and real-time PCR. [3H]Thymidine incorporation was used as an index of DNA synthesis. NOR-1 promoter activity was analyzed using a luciferase reporter system. Cyclic AMP response element binding protein (CREB) binding was assessed by EMSA and ELISA and CREB activation (phosphorylation in Ser133) by Western blotting. Results: Simvastatin inhibited NOR-1 expression induced by LDL in VSMC and by hypercholesterolemia in the abdominal aorta of hyperlipemic pigs. The inhibition of the isoprenylation of geranylgeranylated proteins by simvastatin was key in both NOR-1 up-regulation and DNA synthesis induced by LDL. Inhibitors of RhoA (toxin B and exotoxin C3) and ROCK (Y-27632) mimicked the effect of simvastatin on NOR-1. Similarly both simvastatin treatment and cells transfected with a RhoA dominant-negative (RhoAT19N) showed inhibition of LDL-induced NOR-1 promoter activity. These effects were associated to the interference of the activation of CREB, a key transcription factor involved in NOR-1 induction. Finally, simvastatin prevented LDL induction of a reporter construct containing four consensus CRE and inhibited the expression of SMemb (a marker for dedifferentiated VSMC) dependent on CREB. Conclusions: NOR-1 is a target for simvastatin in the vascular wall. We identified NOR-1 and CREB as key transcription factors mediating the effect of statins on VSMC proliferation through a mechanism dependent on RhoA/ROCK. [Copyright &y& Elsevier]

Solid materials with uniform micropores, such as zeolites, can act as selective catalysts and adsorbents for molecular mixtures by separating those molecules small enough to enter their pores while leaving the larger molecules behind. Zeolite A is a microporous material with a high void volume. Despite its widespread industrial use in, for example, molecular separations and in detergency, its capability as a petroleum-refining material is limited owing to its poor acid-catalytic activity and hydrothermal stability, and its low hydrophobicity. These characteristics are ultimately a consequence of the low framework Si/Al ratio (normally around one) and the resulting high cationic fraction within the pores and cavities. Researchers have modified the properties of type-A zeolites by increasing the Si/Al compositions up to a ratio of three. Here we describe the synthesis of zeolite A structures exhibiting high Si/Al ratios up to infinity (pure silica). We synthesize these materials, named ITQ-29, using a supramolecular organic structure-directing agent obtained by the self-assembly, throughp-ptype interactions, of two identical organic cationic moieties. The highly hydrophobic pure-silica zeolite A can be used for hydrocarbon separations that avoid oligomerization reactions, whereas materials with high Si/Al ratios give excellent shape-selective cracking additives for increasing propylene yield in fluid catalytic cracking operations. We have also extended the use of our supramolecular structure-directing agents to the synthesis of a range of other zeolites. [ABSTRACT FROM AUTHOR]

Reaction of Zn(AcO)2 · 2H2O with 6-methyl-2-pyridinecarboxylic acid (L) yielded a new compound [Zn(MeC5H3NCOO)2(H2O)] · H2O. This complex was characterised by elemental analyses, conductivity measurements, infrared, 1H and 13C{1H} NMR spectroscopies and single-crystal X-ray diffraction. The crystal structure consists of discrete molecules involving a pentacoordinated Zn atom with a geometry intermediate between a trigonal bipyramid and a square pyramid and with the two Npy atoms occupying the apical sites. Treatment of the complex [Zn(MeC5H3NCOO)2(H2O)] · H2O with 2,2′-bipyridine (bpy) produced [Zn(MeC5H3NCOO)2(bpy)]. The metallic atom in this complex displays a distorted octahedral geometry and is coordinated to two ligands (L) via the pyridine nitrogen and the carbonyl oxygen atoms and to one 2,2′-bypyridine (bpy). [Copyright &y& Elsevier]

Calderonite, ideally Pb[sub2]Fe&sup3+;(VO[sub4])[sub2](OH), a new member of the brackebuschite group, has been found in the upper oxidation zone of two Pb-Zn hydrothermal deposits located at Santa Marta and Azuaga, Badajoz province, Spain. Brackebuschite and calderonite probably form a complete solid solution, locally with important substitution of Cu and Zn for Fe and Mn. The monoclinic cell parameters derived from powder X-ray diffraction (XRD) data are: a = 7.647(5) Å, b = 6.094(1) Å, c = 8.900(2) Å, β = 112.0(2)° and V = 384.5(4) ų, and the six strongest lines, d-spacing (Å),(I),(hkl), are: 4.893(4)(011), 4.166(3)(002), 3.242(10) (211), 3.058(3)(020), 2.980(5) (103) and 2.746(5)(003). Electron microprobe analyses (EMPA) show a certain degree of compositional variation not only between the Santa Marta and Azuaga samples but also among grains from the same locality. A representative formula of Santa Marta calderonite, determined from EMPA, based on 9 O atoms: is (Pb[sub1.950]Ca[sub0.004]Ba[sub0.015])[sub1.969](Fe&sup3+;[sub0.892]Cu[sub0.059]Zn[sub0.008]Al[zub0.015])[sub0.974](V[sub1.874]As[sub0.008]Si[sub0.039]P[sub0.057])[sub1.951]O[sub7.507](OH)[sub1.493]. Fe&sup3+; is principally substituted by Cu&sup2+;, and V[sup5+] by Si[sup4+]. ρ[subc] = 6.05 g/cm³. The thermogravimetric analysis yields a weight loss of 1.91%, which corresponds to the 1.493 H needed to maintain the charge balance. Differential thermal analysis shows endothermic effects at 279 and 663 °C due to dehydroxylation. A single-crystal XRD refinement was carried out on a selected crystal with cationic content determined by EMPA and starting atomic positions from brackebuschite. Final R-value of 5.81% based on 952 reflections with I > 2σ[sub1], assuming P2[sub1]/m symmetry, the cell dimensions are a = 7.649 Å, b = 6.101 Å, c = 8.904 Å, β = 112.23°. Calderonite is red orange to red brown, semitransparent... [ABSTRACT FROM AUTHOR]

In 1987, Rius, Plana & Palanques [J. Appl. Cryst. (1987), 20, 457-460] devised an X-ray powder diffraction method based on the 'least-squares' determination of calibration constants using only the diffracted intensities and the calculated absorption coefficients of the components. This method was developed for 'infinitely thick' samples, a condition which is seldom met by airborne particulates because of the small amount of material normally available. Since the analysis of such samples may become one of the principal applications of the method, this condition represents a serious limitation. The simplest way to overcome this limitation is by correcting the measured intensities. This can be done either by direct measurement of the sample transmission, or alternatively, by using refined transmission values. In the latter case no experimental values are necessary. With the help of some test calculations, the viability of both possibilities has been explored. [ABSTRACT FROM AUTHOR]

Background: Patients presenting with the coronavirus-2019 disease (COVID-19) may have a high risk of cardiovascular adverse events, including death from cardiovascular causes. The long-term cardiovascular outcomes of these patients are entirely unknown. We aim to perform a registry of patients who have undergone a diagnostic nasopharyngeal swab for SARS-CoV-2 and to determine their long-term cardiovascular outcomes. Study and design: This is a multicenter, observational, retrospective registry to be conducted at 17 centers in Spain and Italy (ClinicalTrials.gov number: NCT04359927). Consecutive patients older than 18 years, who underwent a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) for SARS-CoV2 in the participating institutions, will be included since March 2020, to August 2020. Patients will be classified into two groups, according to the results of the RT-PCR: COVID-19 positive or negative. The primary outcome will be cardiovascular mortality at 1 year. The secondary outcomes will be acute myocardial infarction, stroke, heart failure hospitalization, pulmonary embolism, and serious cardiac arrhythmias, at 1 year. Outcomes will be compared between the two groups. Events will be adjudicated by an independent clinical event committee. Conclusion: The results of this registry will contribute to a better understanding of the long-term cardiovascular implications of the COVID19. [ABSTRACT FROM AUTHOR]

The ammonium salt of monoethyloxalate (AmEtOx) was investigated as a novel precursor for the conservation of carbonate stone substrates, such as biomicritic limestone and marble. Full characterization of treated and untreated authentic stone samples was carried out by means of SEM, X-ray powder diffraction, synchrotron tts-μXRD measurements, mercury intrusion porosimetry, determination of water transport properties, and pull-off tests. The improved solubility (1.49 M, 20.1% w/w) of AmEtOx as compared to that of ammonium oxalate (AmOx; 0.4 M, 5% w/w) results in the formation of microcrystalline phases 30–50 and 200–500 μm thick of calcium oxalate mono-(whewellite) or dihydrate (weddellite), on marble and biomicrite samples, respectively, after treatment with AmEtOx 5% and 12% w/w aqueous solutions. As a result, a reduction in the porosity of the stone samples and an enhancement of their cohesion are observed. DFT calculations, carried out to investigate the hydrolysis reaction leading from AmEtOx to AmOx, showed that the localization of the Lowest Unoccupied Molecular Orbital (LUMO) and the natural charge distribution account nicely for the tendency to hydrolyse observed experimentally, eventually leading to the formation of whewellite and weddellite on the stone surface. [ABSTRACT FROM AUTHOR]

• Development of silica microcrystals is inferred from morphology and local probe data. • Cristobalite and tridymite can nucleate from iron oxide not requiring alkali metals. • Morphology of silica microcrystals can hide intergrowths and paramorphic phases. • Cristobalite hexagonal plates and dendrites show a tridymite external growth front. Different methods have been historically used to identify silica-polymorph microcrystals in various contexts. However, in the existing literature there is a substantial lack of correlation between local probe analytical data and the corresponding images showing crystal morphologies. Here we demonstrate that such correlation is attainable through an approach based on the characterization of samples prepared as polished thin sections combining optical microscope images with local probe techniques (synchrotron through-the-substrate X-ray microdiffraction and confocal micro-Raman). We report the characterization of different morphologies of silica microcrystals embedded in lead glazes from glazed pottery produced in Jouques (France) in the mid-19th century. Among the eight identified morphologies, are worthy of note cristobalite-coated quartz, paramorphic quartz after cristobalite, cristobalite-tridymite intergrowths or cristobalite twinned crystals. Elusive tridymite has been identified and mapped using μ-Raman and locates predominantly at the borders of some morphologies suggesting a growth front of tridymite that turns to cristobalite. [ABSTRACT FROM AUTHOR]

During the last thirty years, microstructural and technological studies on ceramic glazes have been essentially carried out through the use of Scanning Electron Microscopy (SEM) combined with energy dispersive X-ray analysis (EDX). On the contrary, optical microscopy (OM) has been considered of limited use in solving the very complex and fine-scale microstructures associated with ceramic glazes. As the crystallites formed inside glazes are sub- and micrometric, a common misconception is that it is not possible to study them by OM. This is probably one of the reasons why there are no available articles and textbooks and even no visual resources for describing and characterizing the micro-crystallites formed in glaze matrices. A thin section petrography (TSP) for ceramic glaze microstructures does not exist yet, neither as a field of study nor conceptually. In the present contribution, we intend to show new developments in the field of ceramic glaze petrography, highlighting the potential of OM in the microstructural studies of ceramic glazes using petrographic thin sections. The outcomes not only stress the pivotal role of thin section petrography for the study of glaze microstructures but also show that this step should not be bypassed to achieve reliable readings of the glaze microstructures and sound interpretations of the technological procedures. We suggest the adoption by the scientific community of an alternative vision on glaze microstructures to turn thin section petrography for glaze microstructures into a new specialized petrographic discipline. Such an approach, if intensively developed, has the potential to reduce the time and costs of scientific investigations in this specific domain. In fact, it can provide key reference data for the identification of the crystallites in ceramic glazes, avoiding the repetition of exhaustive protocols of expensive integrated analyses. [ABSTRACT FROM AUTHOR]

For two decades, the nature of Fe-rich, oxygen-bearing, Ru-Os compounds found in the supergene environment has been debated. Ru-Os-Fe-oxides and nano-intergrowths of ruthenium with magnetite have been proposed. We applied FE- SEM, EMPA, μ-Raman spectroscopy and synchrotron tts-μ XRD to Ru-Os-Fe compounds recovered from Ni-laterites from the Dominican Republic. The results demonstrate that a significant portion of Fe exists in a common structure with the Ru-Os alloy, that is, ruthenian hexaferrum. This mineral occurs both as nanoparticles and as micrometric patches within a matrix of Fe-oxide(s). Our data suggest that supergene ruthenian hexaferrum with a (Ru0.4(Os,Ir)0.1Fe0.5)Ʃ1.0 stoichiometry represents the most advanced weathering product of primary laurite within Ni-laterites from the Dominican Republic. [ABSTRACT FROM AUTHOR]

The structural variability of two series of Mg2+- and Zn2+- 2-hydroxyphosphonoacetates have been studied in the range of 25-80 °C and 95 % relative humidity in order to correlate the structure with the proton conductivity properties. In addition to selected previously reported 1D, 2D and 3D materials, a new compound, KZn6(OOCCH(OH)PO3)4(OH)·5H2O (KZn6-HPAA-3D), has been prepared and thoroughly characterized. The crystal structure of this solid, solved ab initio from synchrotron X-ray powder diffraction data, consists of a negatively charged 3D framework with K+ ions, as compensating counterions. It also contains water molecules filling the cavities in contrast to the potassium-free 3D anhydrous NH4Zn(OOCCH(OH)PO3) (NH4Zn-HPAA-3D). In the range of temperature studied, the 1D materials exhibit a 1D → 2D solid-state transition. At 80 °C and 95 % RH, the 2D solids show moderate proton conductivities, between 2.1 x 10 -5 S·cm-1 and 6.7 x 10-5 S·cm-1. The proton conductivity is slightly increased by ammonia adsorption up to 2.6 x 10-4 S·cm-1, although no ammonia intercalation was observed. As synthesized KZn6-HPAA-3D exhibits a low proton conductivity, 1.6 x 10-6 S·cm-1, attributed to the basic character of the framework and a low mobility of water molecules. However, this solid transforms to the 2D phase, Zn(OOCCH(OH)PO3H)·2H2O, upon exposure to dry HCl(g), which enhances the proton conductivity with respect to the as-synthesized 2D material (4.5 x 10-4 S·cm-1). On the other hand, NH4Zn-HPAA-3D exhibited a higher proton conductivity, 1.4 x 10-4 S·cm-1, than the K+ analog. [ABSTRACT FROM AUTHOR]

We present the first magnetic phase of an ionic liquid with anion-π interactions, which displays a three-dimensional (3D) magnetic ordering below the Néel temperature, TN = 7.7 K. In this material, called Dimim[FeBr4], an exhaustive and systematic study involving structural and physical characterization (synchrotron X-ray, neutron powder diffraction, direct current and alternating current magnetic susceptibility, magnetization, heat capacity, Raman and Mössbauer measurements) as well as first-principles analysis (density functional theory (DFT) simulation) was performed. The crystal structure, solved by Patterson-function direct methods, reveals a monoclinic phase (P21 symmetry) at room temperature with a = 6.745(3) Å, b = 14.364(3) Å, c = 6.759(3) Å, and β = 90.80(2)°. Its framework, projected along the b direction, is characterized by layers of cations [Dimim]+ and anions [FeBr4]- that change the orientation from layer to layer, with Fe···Fe distances larger than 6.7 Å. Magnetization measurements show the presence of 3D antiferromagnetic ordering below TN with the existence of a noticeable magneto-crystalline anisotropy. From low-temperature neutron diffraction data, it can be observed that the existence of antiferromagnetic order is originated by the antiparallel ordering of ferromagnetic layers of [FeBr4]- metal complex along the b direction. The magnetic unit cell is the same as the chemical one, and the magnetic moments are aligned along the c direction. The DFT calculations reflect the fact that the spin density of the iron ions spreads over the bromine atoms. In addition, the projected density of states (PDOS) of the imidazolium with the bromines of a [FeBr4]- metal complex confirms the existence of the anion-π interaction. Magneto-structural correlations give no evidence for direct iron-iron interactions, corroborating that the 3D magnetic ordering takes place via superexchange coupling, the Fe-Br···Br-Fe interplane interaction being defined as the main exchange pathway. [ABSTRACT FROM AUTHOR]

We report the synthesis, physicochemical characterization, and crystal structure of Cu-SP (SP = styrylphosphonic acid, H2O3PCH=CH2(C6H5)), the first reported example of a metal derivative of SP. The starting SP acid was fully characterized by X-ray single-crystal diffractometry, elemental analysis (C and H),31P-NMR,13C-NMR,1H-NMR, HPLC, UV–vis, MS, TG, and FT-IR spectroscopy. The copper(II) derivative was synthesized and characterized by DTA-TG and FT-IR, and also its structure was determined from powder data. The crystal structure was refined by the Rietveld method. The crystal structure of Cu-SP shows a layered 2-D architecture, where the organic moieties are pointed toward the interlamellar space. The inorganic layers are composed of Cu2+dimers, where the coordination geometry of Cu2+can be described as distorted trigonal bipyramid. The three coplanar oxygens (O2, O3, and O3) have bond distances of 2.165(9), 1.982(9), and 2.103(11) Å, respectively. The bond lengths for the apical oxygens (O1 and O2) are 1.908(13) and 1.996(11) Å, respectively. [ABSTRACT FROM AUTHOR]

In this paper we report the spectral properties of the stable radical adducts 1*-3*, which ate formed by an electron donor moiety, the carbazole ring and an electron acceptor moiety, the polychlorotriphenylmethyl radical. The molecular structure of radical adduct 1* in the crystalline state shows a torsion angle of approximately 90° between the pheny| and the carbazole rings due to steric interactions. They exhibit a charge transfer band in the visible range of the electronic spectrum. All of them are chemically oxidized with copper(II) perchlorate to the respective cation species, which show a strong charge transfer band into the near-infrared region of the spectrum. Radical adducts 1*-3* and the corresponding stable oxidized species 1+-3+ are real organic mixed-valence compounds due to the open-shell nature of their electronic structure. Charge transfer bands of the cation species are stronger and are bathochromically shifted with respect to those of the neutral species due to the greater acceptor ability of the positively charged central carbon atom of the triphenylmethyl moiety. The cationic species 1+-3+ are diamagnetic, as shown by the absence of a signal in the EPR spectrum in acetonitrile solution at room temperature, but they show an intense and unique band in frozen solutions (183 K). [ABSTRACT FROM AUTHOR]