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IRMOF-10, derived from biphenyl-4,4′-dicarboxylic acid and zinc, is a prototype for an open cubic structure prone to interpenetration. Interpenetration can compromise MOF pore volume and surface area which drives the need to develop strategies to synthesize non-interpenetrated MOFs. In this work, an additive design strategy was employed to suppress interpenetration of IRMOF-10. The presence of the additive during traditional solvothermal synthesis yielded an activated material with the highest surface area reported to date and enabled the determination of the single crystal structure. In situ monitoring of the nucleation of crystals under polarized light provided insights into the mechanism behind interpenetration in the IRMOF-9/10 system. This work provides a roadmap to suppress interpenetration more generically in other MOFs and achieve improved surface areas and pore volumes for this prominent class of porous sorbents. [ABSTRACT FROM AUTHOR]

The inorganic pyrocarbonate salt Ba[C2O5] contains twisted pyrocarbonate anions ([C2O5]2−), an atomic arrangement previously not observed in other pyrocarbonates. This unexpected additional structural degree of freedom points towards an enlarged chemical variability in this novel group of compounds. Ba[C2O5] was synthesized in a laser-heated diamond anvil cell at 30(2) GPa by heating a mixture of Ba[CO3] + CO2 to ≈ 1500(200) K. Its crystal structure was solved from single crystal synchrotron X-ray diffraction data and confirmed by density functional theory-based calculations. The two planar [CO3]2−-groups of the [C2O5]2−-anion are strongly twisted around the bridging oxygen atom. Ba[C2O5] has been observed in the pressure range of 5–30 GPa, where its symmetry is P6/m with Z = 12. [ABSTRACT FROM AUTHOR]

The versatility of early transition metal chalcogenide nanomaterials, including chalcogenide perovskites, has attracted enormous attention for a variety of applications, such as photovoltaics, photocatalysis, and optoelectronic devices. These nanomaterials exhibit unique electronic and optical properties, allowing for a broad range of applications, depending on their chemical composition and crystal structure. However, solution-phase synthesis of early transition metal chalcogenide nanocrystals is challenging due, in part, to their high crystallization energy and oxophilicity. In this feature article, we explore various synthetic routes reported for inorganic ternary and binary sulfide and selenide nanomaterials that include transition metals from groups 3, 4, and 5. By systematically comparing different synthetic approaches, we identify trends and insights into the chemistry of these chalcogenide nanomaterials. [ABSTRACT FROM AUTHOR]

The first instance of a rare-earth single-ion magnet in a robust extended solid has been found, which possesses a crystal structure different from apatite. The compound exhibits slow relaxation of magnetization in a zero field revealing simultaneously two energy barriers for magnetization reversal. [ABSTRACT FROM AUTHOR]

This paper reports a possible mechanism of acetic acid formation from CO2, CH3I and H2 in aqueous media and the central role played by a water-soluble Rh-based electron storage catalyst. In addition to water-solubility, we also report the crystal structures of two presumed intermediates. These findings together reveal (1) the advantage of water, not only as a green solvent, but also as a reactive Lewis base to extract H+ from H2, (2) the role of the metal (Rh) centre as a point for storing electrons from H2 and (3) the importance of an electron-withdrawing ligand (quaterpyridine, qpy) that supports electron storage. [ABSTRACT FROM AUTHOR]

Reactions of trans-[Fe(CO)2(NO)(As((CH2)n)3As)]+ BF4− (n = 10, 12, 14) and Bu4N+ Cl− afford the title compounds As((CH2)n)3As, which upon reaction (n = 14) with MCl2 (M = Pt, Ni), Rh(CO)(Cl), and Fe(CO)3 sources reconstitute cage like complexes trans-MLn(As((CH2)14)3As). Reactions with H2O2 and BH3 give the corresponding arsine oxides and boranes. Crystal structures of metal-free species reveal out,out isomers, but cage complex formation is proposed to entail homeomorphic isomerization to in,in isomers with endo directed lone pairs. [ABSTRACT FROM AUTHOR]

The hollow [PdL][BArF]2 complex 1 of a tetra-pyridyl (py) ligand (L) has a [Pd(py)4]2+ coordination environment. Addition of coordinating anions resulted in the formation of a neutral species with Pd(py)2(anion)2 coordination environment (12A). These species bind further to the coordinating anions in the order Cl− > N3− > Br− > I− > AcO− with Ka1 : 1 ≤ 414 M−1. With relatively non-coordinating anions 1 remains intact and displays 1 : 2 binding behaviour dominated by the 1 : 1 stoichiometry in the order NO3− (∼105 M−1) » ClO4− and BF4− (∼103 M−1). As evidenced by crystal structure data, DFT calculations and {1H–19F}-HOESY NMR with BF4−, the anions are bound by charge assisted [C–H]+···anion interactions. [ABSTRACT FROM AUTHOR]

A new miniprotein built from three helices, including one structure based on the ααβαααβ sequence pattern was developed. Its crystal structure revealed a compact conformation with a well-packed hydrophobic core of unprecedented structure. The miniprotein formed dimers that were stabilized by the interaction of their hydrophobic surfaces. [ABSTRACT FROM AUTHOR]

The new oxonitridosilicates Ln4−xSr2+xSi5N12−xOx (Ln = La, Ce) were synthesized by high temperature solid-state reactions. The crystal structures were solved and refined from both single-crystal and powder X-ray diffraction data. These oxonitridosilicate compounds crystallize in the monoclinic space group P21/n (no. 14) and exhibit a double-layer structure made up of corner-sharing Si(O/N)4 tetrahedra. When excited with near-UV and blue light, the Pr3+ doped La2.31Sr3.69Si5N10.31O1.69 phosphor shows a narrow-band red emission peaking at 625 nm with a full width at half-maximum of 40 nm. [ABSTRACT FROM AUTHOR]

Single-crystal nanooptomechanical transduction occurs in [Ru(SO2)(NH3)4(H2O)]chlorobenzenesulfonate2, reaching maximal levels within 40 s at 100 K when photostimulated by 505 nm light. Its in situ light-induced crystal structure reveals the molecular origins of this optical actuation: 26.0(3)% of the η1-SO2 ligand photoconverts into an η1-OSO photoisomer which, in turn, induces a 49.6(9)° arene ring rotation in its neighbouring counter ion. [ABSTRACT FROM AUTHOR]

As early as 1837, Liebig synthesised solid C2H5ONa. Today, C2H5ONa is one of the standard bases in organic synthesis. Here, we report the identification of different solid phases and the crystal structures and phase transformations of C2H5ONa and C2H5ONa·2C2H5OH. [ABSTRACT FROM AUTHOR]

Single crystals of Spiro(TFSI)2 were grown, the optical and electronic properties were characterized and compared with neutral Spiro-OMeTAD. Density-functional theory was used to get insights into binding and band structure properties. The flat valence bands indicate a rather limited orbital overlap in Spiro(TFSI)2. [ABSTRACT FROM AUTHOR]

Anisotropic dodecahedral (D) water cages found in semiclathrate hydrates have unique gas selectivity due to their varied shapes. Herein, the D cages incorporating ideally isotropic rare gases, i.e., Xe, Kr and Ar, were characterized by crystal structure analyses. Stabilization mechanisms of the semiclathrate hydrates by the D cages are discussed. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are often, and incorrectly, believed to be purely crystalline solids. This Feature Article highlights a selection of highly disordered MOF-based materials. This disorder gives rise to numerous possibilities in the fabrication of new MOF materials, and presents an alternative method of novel materials discovery, outside of the synthesis of increasingly complex crystalline structures. The formation of liquid MOFs and resultant melt-quenched glasses is reviewed, along with several categories of novel MOF-based materials including blends, flux melted glasses and crystal–glass composites. [ABSTRACT FROM AUTHOR]

Herein, we report the crystal structures of the antimicrobial agent diiodomethyl-p-tolylsulfone and of three halogen bonded co-crystals demonstrating that the bioactive moiety –SO2CHI2 can function as a quite effective halogen bond based motif in the solid state and in solution, namely demonstrating that α-iodosulfones may become a new entry in the quite small group of alkyl-iodides functioning as reliable halogen bond-donors. [ABSTRACT FROM AUTHOR]

A silicon–aluminum heterocycle LAl(SiH2SiH2)2AlL (L = PhC(NtBu)2) (1) was prepared. Compound 1 exhibits a unique (N2Al)2(SiH2)4 centrosymmetric six-membered ring structure with a chair conformation, which is comparable with that of cyclohexane. Furthermore, two intermediate analogues, silylene–alane adduct LSi(AlMe3)–Si(AlMe3)L (2) and silylene–alane oxidative product [LAlHSiH2Mes]2 (3) were obtained. Compound 3 has an interesting arrangement of an Al–H and an SiH2 unit, which are in close vicinity to each other. 3 might be important to function as a catalyst, due to the already activated bridging Al–H bonds. [ABSTRACT FROM AUTHOR]

A complex [Au(NHC)2][Au(C≡N)2] double salt exhibits polymorphic crystalline structures with distinct phosphorescence and variations at Au⋯Au distances and ligand–ligand torsion angles. This serves as a model system correlating aurophilicity and low-energy charge-transfer electronic transitions and helps to understand the thermochromism and mechanochromism of the gold(I) complexes. [ABSTRACT FROM AUTHOR]

This review focuses on the synthesis, properties and selected applications of heavy pnictogen chalcohalides, i.e. compounds of the MQX stoichiometry, where M = As, Sb, and Bi; Q = O, S, Se, and Te; and X = F, Cl, Br and I. The first section focuses on their synthesis and crystal structures, and the second section discusses the electronic structure on the basis of quantum chemical modelling and selected experimental data. Finally, the third section discusses their electrical, photoelectrochemical and photocatalytic properties and applications. In contrast to perovskites, chalcopyrites and kesterites, chalcohalides have attracted relatively less attention, but their structure and properties are well suited for numerous applications. [ABSTRACT FROM AUTHOR]

A re-refinement of the published but chemically implausible, crystal structure of "Form III" of 4-bromophenyl 4-bromobenzoate shows that it is not a polymorph, but instead a co-crystal containing both 4-bromophenyl 4-bromobenzoate (≈25%) and likely 4-bromophenyl 4-nitrobenzoate (≈75%). [ABSTRACT FROM AUTHOR]

Donor-unsupported iso-butyllithium consists of hexamers with an ordered triclinic structure at −80 °C (α-phase). At ambient temperature, the compound exists as an orthorhombic, remarkably stable, plastic-crystalline γ-phase, which is built by disordered hexamers adopting a distorted face-centred cubic packing. Both structures were determined by X-ray powder diffraction. Additionally, an intermediate β-phase is observed. [ABSTRACT FROM AUTHOR]

Switching from positive to negative axial thermal expansion in pure organic materials is reported for the first time. This rare phenomenon has been rationalized based on the packing of molecules in crystal structures and transverse thermal vibrations of atoms in the molecule. Unique packing of the molecules in the crystal structure contributes to the restricted movement of molecules along the c axis. Subsequently, contraction of molecular dimensions with increasing temperature, due to transverse vibrations of some atoms, assists with the switch from Positive Thermal Expansion (PTE) to Negative Thermal Expansion (NTE). [ABSTRACT FROM AUTHOR]

Crystal structure determination and mutagenesis analysis of a cis-epoxysuccinate hydrolase which produces enantiomerically pure d(−)-tartaric acids revealed a zinc ion and essential residues in the stereoselective mechanism for the catalytic reaction of the small mirror symmetric substrate. [ABSTRACT FROM AUTHOR]

The crystal structure of the Escherichia coli O2-sensitive C19G [NiFe]-hydrogenase-1 variant shows that the mutation results in a novel FeS cluster, proximal to the Ni–Fe active site. While the proximal cluster of the native O2-tolerant enzyme can transfer two electrons to that site, EPR spectroscopy shows that the modified cluster can transfer only one electron, this shortfall coinciding with O2 sensitivity. Computational studies on electron transfer help to explain how the structural and redox properties of the novel FeS cluster modulate the observed phenotype. [ABSTRACT FROM AUTHOR]

We investigate the variable temperature (100–450 K) and high-pressure (p = ambient − 0.74 GPa) crystal chemistry of the black perovskite formamidinium lead iodide, [(NH2)2CH]PbI3, using single crystal X-ray diffraction. In both cases we find a phase transition to a tetragonal phase. Our experimental results are combined with first principles calculations, providing information about the electronic properties of [(NH2)2CH]PbI3 as well as the most probable orientation of the [(NH2)2CH]+ cations. [ABSTRACT FROM AUTHOR]

Ureidosalicylic acid forms remarkable trimeric cyclamer-like crystal structures with either three or six independent molecules in the asymmetric unit as a result of the excess of hydrogen bond donors and guest inclusion within the centre of the cyclamer. The structures persist in solution in hydrogen bond acceptor solvents suggesting a role for solution pre-association in forming high Z′ structures. [ABSTRACT FROM AUTHOR]

New examples of uranium in the formal +2 oxidation state have been isolated by reduction of Cptet3U (Cptet = C5Me4H) and U(NR2)3 (R = SiMe3) in the presence of 2.2.2-cryptand (crypt) to produce [K(crypt)][Cptet3U] and [K(crypt)][U(NR2)3], respectively. Both complexes have properties consistent with 5f36d1 electron configurations and demonstrate that the U(ii) ion can be isolated with electron donating ligands. [ABSTRACT FROM AUTHOR]

A 3-fold interpenetrated Ag(i) coordination framework can exhibit dual structure evolution behaviours driven by distinct anion-exchange courses in which irreversible single-crystal to single-crystal transformation occurs, resulting in a switching of network interpenetration degree (from 3-fold to 2-fold). [ABSTRACT FROM AUTHOR]

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A novel 3D MOF based on dysprosium(iii) oxalate and 1,10-phenanthroline (phen), {[Dy(C2O4)1.5phen]·0.5H2O}n (1), has been hydrothermally synthesized. The Dy3+ ion acts as a typical Y-shaped node, linking to each other to generate an interesting 3D topology structure. Complex 1 is the first 3D DyMOF displaying both ferromagnetic coupling and field-induced two-step magnetic relaxation. [ABSTRACT FROM AUTHOR]

Fluorescent nanodots have become increasingly prevalent in a wide variety of applications with special interest in analytical and biomedical fields. The present overview focuses on three main aspects: (i) a systematic description and reasonable classification of the most relevant types of fluorescent nanodots according to their nature, quantum confinement and crystalline structure is provided, starting with a clear distinction between semiconductor and carbon-based dots (graphene quantum dots, carbon quantum dots and carbon nanodots). A new set of abbreviations and definitions for them to avoid contradictions found in literature is also proposed; (ii) a rational classification allows the establishment of clear-cut differences and similarities among them. From a basic point of view, the origins of the photoluminescence of the different nanodots are also established, which is a relevant contribution of this overview. Additionally, the most outstanding similarities and differences in a great variety of criteria (i.e. year of discovery, synthesis, the physico-chemical characteristics like structure, nature, shape, size, quantum confinement, toxicity and solubility, the optical characteristics including the quantum yield and lifetime, limitations, applications as well as the evolution of publications) are thoroughly outlined; and (iii) finally, the promising future of fluorescent nanodots in both analytical and biomedical fields is discussed using selected examples of relevant applications. [ABSTRACT FROM AUTHOR]

For the first time, three iron(iii) porphyrinato complexes have been synthesized selectively by varying the iodine concentration in the reaction mixture which eventually forms both five and six coordinate complexes with iodide and/or tri-iodide as axial ligands. Combined analysis using single crystal X-ray structure determination, and Mössbauer, 1H NMR and EPR studies as well as VT magnetic studies has revealed the admixed-intermediate (iodo complex), pure intermediate (tri-iodide complex) and high-spin (1e-oxidized complex) states of iron. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of luminogenic, bioorthogonal iridium probes is described. These probes exhibit long photoluminescence lifetimes amenable to time-resolved applications. A simple, modular synthesis via 5-azidophenanthroline allows structural variation and allows optimization of cell labeling. [ABSTRACT FROM AUTHOR]

Triple-stranded dinuclear nickel(ii) complexes of the meso-helicate type have been obtained from the new N,N′-1,3-phenylenebis(pyrazine-2-carboxamidate) ligand; they possess a multielectron redox behaviour featuring up to four stepwise, one-electron oxidation reactions of the two ferromagnetically coupled NiII ions to afford the putative high-valent dinickel(iii) and dinickel(iv) species, as supported by theoretical calculations. [ABSTRACT FROM AUTHOR]

The surface and interface are considered as the crucial features that can be engineered to improve the performance of catalysts. The great advancements in both controlled syntheses and catalytic mechanism studies have paved the way for the rational surface and interface design of catalysts. In this feature article, we overview our recent progress in surface and interface design for well-defined hybrid structures mainly toward the photocatalytic and electrocatalytic applications in which charge carriers play an important role. First, we outline the surface parameters of components including exposed facets, compositions, surface areas and crystal phases that have been tailored toward higher surface activation abilities for electrocatalytic and photocatalytic reactions. Second, we summarize the designing rules for the interface between two components to favor the charge transfer for photocatalytic reactions on the surface. Furthermore, we outline the synergistic effects on photocatalysis and electrocatalysis through the simultaneous control of the surface and the interface, which can also be extended to enhance other catalytic reactions (e.g., CO oxidation). Finally, we discuss the challenges and opportunities for further development of surface and interface design toward catalytic performance tuning. [ABSTRACT FROM AUTHOR]

Core@shell Co@Au nanoparticles of around 8 nm have been produced by the inert gas condensation method, revealing for the first time that most of the nanoparticles exhibit an icosahedral shape in agreement with the theoretical prediction. Additionally, we report the existence of a novel morphology which consists of a Co icosahedron surrounded by fcc Au facets, reported here for the first time. [ABSTRACT FROM AUTHOR]

Recently, the results of experimental and theoretical investigations have revealed that, in vaterite, two or even more crystalline structures coexist. In this communication we report evidence of diverse vaterite structures in biogenic samples of different origin. In addition, it is shown that the synthetic vaterite precipitated in the presence of poly-L-aspartate has structures similar to those of biogenic samples. [ABSTRACT FROM AUTHOR]

With the earth's abundance of kesterite, recent progress in chalcogenide based Cu2ZnSn(Sx,Se1-x)4 (CZTSSe) thin films has drawn prime attention in thin film solar cells (TFSCs) research and development. This review is focused on the current developments in the synthesis of CZTS nanocrystals (NCs) using a hot injection (HI) technique and provides comprehensive discussions on the current status of CZTSSe TFSCs. This article begins with a description of the advantages of nanoparticulate based thin films, and then introduces the basics of this technique and the corresponding growth mechanism is also discussed. A brief overview further addresses a series of investigations on the developments in the HI based CZTSSe NCs using different solvents in terms of their high toxicity to environmentally benign materials. A variety of recipes and techniques for the NCs ink formulation and thereby the preparation of absorber layers using NC inks are outlined, respectively. The deposition of precursor thin films, post-deposition processes such as sulfurization or selenization treatments and the fabrication of CZTSSe NCs based solar cells and their performances are discussed. Finally, we discussed concluding remarks and the perspectives for further developments in the existing research on CZTSSe based nanoparticulate (NP) TFSCs towards future green technology. [ABSTRACT FROM AUTHOR]

The asymmetric redox-active ligand 4,5-bis(pyridine-2-carboxamido)-1,2-catechol (N,OLH4) is prepared and metalated to afford the hexanuclear complex [Mn6(N,OL)6]6−. Structural analysis and magnetic measurements reveal this complex to feature MnII ions bridged by N,OL3−Ṗ radicals, which are antiferromagnetically coupled to give an S = 12 ground state. [ABSTRACT FROM AUTHOR]