Optical modulation of the crystal structure and materials properties is an increasingly important technique for functionalization of two-dimensional and layered semiconductors, where traditional methods like chemical doping are ineffective. Controllable transformation between the semiconducting (H) and semimetallic (T') polytypes of transition metal chalcogenide monolayers is of central importa...

A detailed set of synthetic and crystallographic guidelines for the crystalline sponge method based upon the analysis of expediently synthesized crystal sponges using third-generation synchrotron radiation are reported. The procedure for the synthesis of the zinc-based metal-organic framework used in initial crystal sponge reports has been modified to yield competent crystals in 3 days instead ...

Absolute asymmetric photocyclization of isopropylbenzophenone derivatives was achieved by means of a cocrystal approach. Three chiral salt crystals formed by carboxylic acid derivatives with achiral amines could be prepared by spontaneous crystallization. In the M-crystal of 4-(2,5-diisopropylbenzoyl)benzoic acid with 2,4-dichlorobenzylamine, a twofold helical arrangement occurs in a counterclo...

Alumina nanorods were prepared from chromium-containing alumina sludge, and the effects of doping elements, such as Cr, Fe, and Mg, were researched. The results show that the crystal transformation of alumina is restricted by the doped Cr and facilitated by the doped Fe and Mg, which is transformed from θ-Al2O3 to α-Al2O3 in the calcination process. Meanwhile, the crystal transformation of alum...

A bimetallic pentadecanuclear cyanido-bridged {Fe9[W(CN)8]6 (MeOH)24}·xMeOH cluster of an Fe(II/III)-W(IV/V) mixed valence nature, reveals a reversible single-crystal-to-single-crystal transformation, concomitant with metal-to-metal charge transfer between Fe and W ions. The dominance of (HS)Fe(II)-NC-W(V) units at a high temperature, and (HS)Fe(III)-NC-W(IV) units at a low temperature, leads t...

Transformation of deuterated ethanol from supercooled liquid into a plastic crystal or rotator phase is investigated by means of a particular experimental setup combining simultaneously dielectric spectroscopy with neutron diffraction techniques. We demonstrate that, previous to the growth of the bcc lattice of the plastic crystal phase, the formation of a precursor or intermediate phase throug...

New chiral MOFs, assembled from Y(III), Na(I) and chiral flexible-achiral rigid dicarboxylate ligands, have been obtained as single phase under hydrothermal conditions and their structures were solved by single-crystal XRD. The powder X-ray thermodiffractometry study was performed, and reveals that the dehydration of both compounds is accompanied by phase transformation, while the spontaneous r...

A new 2D highly flexible and breathing porous framework [CuL(Me2NH)]·DMF·H2O () (H3L = 5-(4'-carboxylphenoxy)nicotinic acid) has been synthesized using a tritopic linker with a flexible joint. The desolvated framework, [CuL(Me2NH)] (), undergoes structural contraction, and exhibits selective and double-step hysteretic adsorption for CO2. Furthermore, on exposure to CH2Cl2 at room temperature, a...

We design and fabricate a new taper structure for adiabatic mode transformation in two-dimensional photonic-crystal waveguides patterned into a GaInAsP confining layer. The taper efficiency is validated by measurement of a reduction of the reflection between an access ridge and a photonic-crystal guide with one missing row from 6% to less than 1%. This taper is then incorporated into a 60 degre...

Co-crystallisation of 1,8-naphthalenedicarboxylic acid (1,8-nap) with trans-1-(3-pyridyl)-2-(4-pyridyl)ethylene (3,4-bpe) gives a discrete molecular solid-state assembly, 2(3,4-bpe).2(1,8-nap) 1, that is held together by four O-H...N hydrogen bonds wherein the diacid directs a regiocontrolled [2 + 2] photodimerization; the reaction occurs by way of a single-crystal-to-single-crystal transformat...