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Despite borate‐sulfates composed of isolated borate and sulfate groups have been discovered for more than one century, borosulfates of B‐O‐S bonding have not been synthesized until 2012 and their properties remain rarely explored. Here, we report a new borosulfate, namely LiRb4[B(SO4)4], which shows potential as a bran‐new class of deep‐UV nonlinear optical (NLO) material. Remarkably, according to the in situ single‐crystal X‐ray diffraction, LiRb4[B(SO4)4] undergoes successive first‐order phase transitions with incommensurate structural modulations under room temperature and low temperature with (3 + 1)D superspace groups of X2(α0γ)0 and P21(α0γ)0, respectively. The first‐principle calculations and structural analyses reveal that NLO properties, phase transitions, and incommensurate modulations are closely related to the [B(SO4)4]5− super‐tetrahedral units with B‐O‐S bonding. We anticipate that the unprecedented coexistence of deep‐UV transparency, NLO responses, and incommensurate structural modulations in one borosulfate will bring new possibilities to understand the underlying concepts of physics and chemistry in aperiodic materials. [ABSTRACT FROM AUTHOR]

Abstract: Fast switching of spontaneous polarization (Ps) is one of the most essential requirements for ferroelectrics used in the field of data storage. However, in contrast to inorganic counterparts, the low operating frequency (<500 Hz) for molecular ferroelectrics severely hinders their large‐scale applications. Herein, for the first time, we achieved the room‐temperature fastest switching of the Ps in a new molecular ferroelectric, N‐methylmorpholinium trinitrophenolate (1), which displays notable ferroelectricity (Ps=3.2 μc cm−2). Strikingly, electric polarizations of 1 have been switched under a record‐high frequency of 263 kHz, and this performance remains stable without any obvious fatigue after ca. 2×105 switching cycles. To our knowledge, 1 is the first organic ferroelectric to switch polarization at such a high operating frequency, exceeding the majority of organic ferroelectrics, which opens up new possibilities for its potential in the field of non‐volatile memory. [ABSTRACT FROM AUTHOR]

Abstract: We evaluated the individual atom contributions to the second harmonic generation (SHG) coefficients of LiCs2PO4 (LCPO) by introducing the partial response functionals on the basis of first principles calculations. The SHG response of LCPO is dominated by the metal‐cation‐centered groups CsO6 and LiO4, not by the nonmetal‐cation‐centered groups PO4 expected from the existing models and theories. The SHG coefficients of LCPO are determined mainly by the occupied orbitals O 2p and Cs 5p as well as by the unoccupied orbitals Cs 5d and Li 2p. For the SHG response of a material, the polarizable atomic orbitals of the occupied and the unoccupied states are both important. [ABSTRACT FROM AUTHOR]

In this report, two totally new indium-tetracarboxylate framework isomers based on the same starting tetracarboxylate ligand are presented, namely, [Me2NH2][In(BPTC)]·Guest (InOF-12) and [Hdabco][In(BPTC)]·Guest (InOF-13). Their corresponding crystal structures essentially originated from the guest templates and were then fully characterized and solved by single crystal X-ray diffraction analysis. Through low pressure gas capacity comparison, it is noted that desolvated InOF-12 exhibits a better performance and its H2 isotherm reaches a high uptake capacity value of 1.32 wt% at 77 K and 1.0 bar, and a high carbon dioxide uptake of 82.2 cm3 g−1 (3.67 mmol g−1) at 273 K and 1.0 bar, while InOF-13 has a lower value of 80.4 cm3 g−1 (3.59 mmol g−1) under the same conditions. [ABSTRACT FROM AUTHOR]

A nonlinear optical phosphate Ba5P6O20 was rationally developed by a tailored synthetic approach based on the use of flexible [P3O10]5− units. The phosphate exhibits a very short absorption edge of λ=167 nm, which is among the shortest known in phase-matchable phosphates. First-principles electronic structure analysis elucidated the origin of the changes in the optical properties, and specifically in the absorption edge, of the material. Such a tailored synthetic approach provides a new opportunity to design nonlinear optical materials with short absorption edges. [ABSTRACT FROM AUTHOR]

Control by encapsulation: A dimeric capsule assembled from a tripodal host by van der Waals forces can stabilize a series of reactive molecules, such as cyclopentadiene and trichlorosilane, in the crystalline state even under relatively harsh conditions. Moreover, these reactive molecules can be controllably released into liquid media for further chemical reaction by thermal programming, leaving the insoluble host molecules behind for easy separation and reuse (see scheme). [ABSTRACT FROM AUTHOR]

The reaction of 2,2'-bipyrazine (bpz) and Cu(NO3)2 with addition of HCl gave a new complex [Cu5(bpz)2Cl10(H2O)]n · nH2O, with bpz serving as a µ3-ligand to link three different copper centers. X-ray crystallography shows a self-assembled supermolecule formed by [Cu5(bpz)2] repeating unit further bridged through Cl-. This is the first Cu(bpz) complex which possesses extended topology instead of closure. Magnetic susceptibility measurements for this complex from 2 to 300 K reveal weak antiferromagnetic interactions between copper(II) in agreement with out-of-plane exchange pathways and large Cu-Cu separation. [ABSTRACT FROM AUTHOR]

Transparent AlON ceramic was pressurelessly sintered from powder synthesized by direct nitridation of Al–Al 2 O 3 starting mixtures. TG, SEM and XRD analyses were conducted to investigate the detail procedure of direct nitridation. The Al spheres were dispersed by submicron Al 2 O 3 , then nitrided and reacted with Al 2 O 3 to form AlON. The particle size of AlON is about 10–30 μm with irregular morphology. With the aid of ball milling and sintering additives, 2 mm thick AlON ceramic with in-line transmittance of 80.6% at 1100 nm and above 77.1% at 400 nm was obtained successfully, demonstrating that the direct nitridation method is another promising approach for the preparation of AlON ceramics with high transparency. [ABSTRACT FROM AUTHOR]

Abstract: It is revealed that TiO2 nanotube arrays fabricated by anodization of the widely used polycrystalline hexagonal Ti foils have a bimodal pore size distribution rather than the commonly believed monomodal distribution manner. As characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), it is shown that nanotubes grown on the Ti (0001) plane have thinner barrier thickness, smaller pore size, shorter tube length and better crystallinity than those grown on other planes, due to the enhanced electron transfer reaction and lower oxide formation efficiency on the Ti (0001) plane. When (0001) oriented Ti thin films deposited by RF magnetron sputtering are anodized, the pore sizes of the grown anodic TiO2 nanotubes distribute monomodally and are close to the smaller pore size of the bimodally distributed TiO2 nanotubes grown on polycrystalline Ti foils under the same conditions. [Copyright &y& Elsevier]

Abstract: A series of Na5La1−x Eu x (WO4)4 (x=0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0) phosphors have been synthesized successfully by a solid-state reaction technique and characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Rietveld refinement. The photoluminescent properties have also been systematically investigated under the near-ultraviolet light. High concentration of doped Eu3+ enhanced the UV absorption and consequently red emission without concentration quenching. The Na5Eu(WO4)4 phosphor was observed a strong red emission under 395nm excitation, bearing with 47% quantum efficiency and the CIE chromaticity coordinates (x=0.67, y=0.33) being close to the National Television Standard Committee (NTSC) standard values. The primary studies indicate that Na5Eu(WO4)4 is a promising candidate as the red phosphor for white light-emitting diodes (LEDs). [Copyright &y& Elsevier]

Abstract: Five metal–organic coordination polymers constructed from tris(p-carboxylphenyl)phosphine oxide (TPO), namely, [Ni3(TPO)2(2,2′-bipy)2(H2O)6] n ·2nH2O (1), [Ni3(TPO)2(phen)2(H2O)6] n ·2nH2O (2), [Ni3(TPO)2(bpe)3(H2O)8] n ·4nH2O (3), [Mn(TPO)(2,2′-bipy)(H2O)] n ·nH2O (4) and [Mn(BPO)(phen)] n (5) (BPO=bis(4-carboxylphenyl)phosphinic acid, bpe= trans-1,2-bis-(4-pyridyl)ethylene, 2,2′-bipy=2,2′-bipydine, phen=1,10-phenanthroline), were hydrothermally synthesized and determined by single-crystal X-ray diffraction analyses. Both of the bpy and phen ligands tailor the NiII complexes 1 and 2 into the ladder-like 1D chain geometries, while the bpe as a bridging ligand leads the NiII complex 3 to form a 2D plane geometry. It is interesting to find that the 2,2′-bipy and phen play a different role in the construction of MnII complexes 4 and 5; where complex 4 crystallizes in a chiral P212121 space group, while a new BPO ligand is formed from the in situ reaction of TPO in 5. Each Pf BPO in 5 links with two MnII ions leading to new [Mn2(PO)2] cluster, and the clusters are bridged by four BPO ligands to give a ring-like structure. [Copyright &y& Elsevier]

Abstract: Two novel coordination polymers [Ca4(C4AS)2(μ3-2,2′-bpno)•15H2O] n •2nH2O (1) and [Cu(H2O)6] n •[Cu2(TC4AS)(μ-2,2′-bpno)•3H2O] n •10nH2O (2) (C4AS=p-sulfonato-calix[4]arene, TC4AS=p-sulfonatothiacalix [4]arene and 2,2′-bpno=2,2′-bipyridine-1,1′-dioxide) have been synthesized and characterized. X-ray diffraction analyses reveal that the rail-like chains of 1 composed of bicapsule units in upper-to-upper way are parallel to the bilayers of 1, whereas the zigzag-like chains of 2 made up of capsules via upper-to-lower mode run through the bilayers of 2. The magnetic properties of complex 2 were examined, indicating weak ferromagnetic interactions between the copper(II) ions in the temperature range of 20–300K. [Copyright &y& Elsevier]

Abstract: The assembly of Ni(II) ions with linear spacers trans,trans-muconic acid (H2L) and 4,4′-bipyridine (4,4′-bpy) has afforded a compound, [Ni(L)(4,4′-bpy)(H2O)2] n (1). Single crystal X-ray diffraction analysis reveals that both 4,4′-bpy and deprotonated H2L act as linear bridges to bind square-planar Ni(II) nodes. Achiral ligands 4,4′-bpy induced in a chiral configuration link metal nodes into chiral chains, which are further bound into homochiral sheets by rigid L. Finally, a novel 3D chiral framework forms through three-fold slantwise interpenetration of those chiral (4,4) nets. The magnetic studies in the range 2–300K show that magnetic behavior of 1 possesses a large zero-field splitting of Ni(II) ions and an anti-ferromagnetic interaction between metal centers. [Copyright &y& Elsevier]

A flexible Zr-based metal–organic framework with a flu topology can respond to temperature and solvent molecules, whose stimuli-responsive mechanism can be explored through in situ single-crystal X-ray diffraction experiments. [Display omitted] • A flexible Zr-based metal organic framework with a flu topology is constructed with the Zr 6 cluster and a fully deprotoned tetratopic ligand. • This complex can respond to temperature and solvent molecules via structural transformations. • The thermal expansion coefficients of uniaxial and unit cell volume can reach up to 612.9 × 10−6 K−1 and 381.9 × 10−6 K−1 respectively. • The stimuli-responsive mechanism can be explored through in situ single-crystal X-ray diffraction experiments. Generally, Zr-MOFs are regarded as rigid and robust. However, we present here a Zr-based flexible metal-organic framework with flu topology (TCBP-F-Zr), whose framework can respond to temperature and solvent molecules via structural transformations. Interestingly, this process can be observed through single-crystal X-ray diffractions. TCBP-F-Zr has a salient anisotropic thermal expansion property from 100 to 298 K. The thermal expansion coefficients of uniaxial and unit cell volume can reach up to 612.9 × 10−6 K−1 and 381.9 × 10−6 K−1 respectively, which is rarely seen in solid materials, especially in Zr-based MOFs. The stimuli-responsive mechanism reveals that structural evolutions are mainly related to twisting of central biphenyl rings of organic ligand. [ABSTRACT FROM AUTHOR]