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Performance of electrocatalytic reactions depends on not only the composition and structure of the active sites, but also their local environment, including the surrounding electrolyte. In this work, we demonstrate that BF2(OH)2− anion is the key fluoroborate species formed in the mixed KBi/KF (KBi=potassium borate) electrolyte to enhance the rate of the oxygen evolution reaction (OER) at near‐neutral pH. Through a combination of electrokinetic and in situ spectroscopic studies, we show that the mixed KBi/KF electrolyte promotes the OER via two pathways: 1) stabilizing the interfacial pH during the proton‐producing reaction with its high buffering capacity; and 2) activating the interfacial water via strong hydrogen bonds with F‐containing species. With the KBi/KF electrolyte, electrodeposited Co(OH)2 is able to achieve 100 mA/cm2 at 1.74 V, which is among the highest reported activities with earth‐abundant electrocatalysts at near neutral conditions. These findings highlight the potential of leveraging electrolyte‐engineering for improving the electrochemical performance of the OER. [ABSTRACT FROM AUTHOR]

An in-depth analysis on the cooperativity of intermolecular interactions including hydrogen bonding and p-p stacking in 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) crystal was studied. Two quantities, cooperativity rate and energy, were defined to evaluate the nature and strength of cooperativity in a series of clusters diverging from 1D to 3D prototypes. The origin and mechanism of the cooperative effect were settled to demonstrate that the nature of cooperativity is determined by whether the non-covalent interactions compete or promote with each other, which is manifested by the changing trend of electron transfer. There exists obvious cooperative effect in intra-layer and inter-layer structures as they own the equivalent non-covalent interactions, while anti-cooperative effect is also observed if two interactions correlate with each other. On the whole, in the process of crystal formation, the apparent cooperativity is the check and balance of the two effects, which is capable to support a global interaction among all of molecules and contribute to the stabilization of system. Based on the results, one may get a new insight to understand the relationship between non-covalent interactions and low impact sensitivity. [ABSTRACT FROM AUTHOR]

Anionocages have been developed as a unique family of hydrogen bonded cages. However, strategies for constructing anionocages are mainly limited to that based on (PO43−)‐bisurea coordination, neither the ligands nor the anions lack the simplicity and diversity of the maturely developed analogues based on metal coordination (i.e. metallocage). We report herein a more simple strategy for anionocages design based on (RPO32−)‐monourea coordination, utilizing monourea rather than bisurea as the hydrogen binding donor, and RPO32− rather than PO43− as the acceptor. Two fluorescent, quadruple helicate anionocages were constructed by a bis‐monourea ligand, and dianions PhOPO32− (H1) or HOPO32− (H1A), respectively, which were capable of encapsulating a series of cation guests. As revealed by molecular modeling, H1 features remarkable guest‐adaptive cavity breathing without change of the quadruple helicate topology, which allowed the encapsulation of different sized guests in an "induced fit" manner. [ABSTRACT FROM AUTHOR]

Several representative ionic liquids (ILs) were synthesized, and [Emim]OAc was chosen as environment-friendly solvent for enzymatic in situ saccharification in view of its biocompatibility with both natural and microcrystalline cellulose, as well as its enzymatic activity. With the microwave pretreatment of natural and microcrystalline cellulose, directly enhancing the in situ enzymatic saccharification, the rate was compared versus an untreated control by the detection of dinitrosalicylic acid (DNS). It is suggested that the molecular structure of cellulose in the process of pretreatment was changed, e.g. intramolecular hydrogen bonds were broken (detected by FT-IR), and the crystallinity (monitored by SEM and XRD) changed significantly from a crystalline to an amorphous pattern. These changes of cellulose led to an increase of reducing sugar conversion during cellulose enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]

The article describes the crystal structure of 5-(4,5-ethylenedithio-1,3-dithiol-2-yl-idene)-1,3,4,6-tetrathiapentalen-2-one (EDTO-TTP) and 5-[4,5-(ethene-1,2-diyldithio)-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalen-2-one (VDTO-TTP). It shows the planar conformation adopted by EDTO-TTP molecule as well as the similarity of the bond characteristics of both compounds. Also reported is the intermolecular interactions exhibited by the EDTO-TTP crystal structure, including transverse and longitudinal interactions, and hydrogen bonding.

We report a simple method to prepare biodegradable polymer−amphiphile complexes by solution mixing of poly(propylene carbonate) (PPC) with octadecanoic acid (OA). The complexes were characterized by combination of thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS), polarizing optical microscopy (POM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). Compared with the amorphous PPC copolymer, the PPC−OA- xcomplexes show excellent thermal stability and form thermotropic liquid crystalline state without rigid mesogenic units. The corresponding mechanism has been proposed to elucidate the observed phenomena. The stabilization effect induced by hydrogen-bonding interactions between PPC and OA molecules is responsible for the thermostability and formation of liquid crystalline state. The present findings may extend the applications of such biodegradable aliphatic polycarbonate by improving its glass transition temperature and thermoplastic processability. [ABSTRACT FROM AUTHOR]

The title polymeric compound, {[MnHg(SCN)4(H2O)]-C4H8O2S}n, consists of slightly distorted MnN4O2 octahedra and HgS4 tetrahedra. Each MnII ion is bound to N atoms belonging to the thiocyanate (SCN) groups and to two O atoms of adjacent water ligands. The sulfolane molecule connects with the coordinated water molecule through hydrogen bonding. Each HgII atom is coordinated by four SCN S atoms. The two adjacent MnII atoms and two O atoms of bridging water molecules connect with one another and form a parallelogram. Each pair of MnII and HgII atoms is connected by an -SCN- bridge, forming an infinite three-dimensional structure. [ABSTRACT FROM AUTHOR]

In the title compound, C7H11O3PS4, the five-membered ring is in an envelope conformation. The average values of the S—C sp3 and S—C sp2 bond lengths are 1.813 (6) and 1.755 (8) Å, respectively. The crystal packing is stabilized by weak inter­molecular C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title complex, [ZnCl(C4H8N2S)3]Cl, comprises [ZnCl(ATU)3]+ cations (ATU is allyl­thio­urea) and Cl− anions, both of which lie on threefold axes. The three S atoms of the allyl­thio­urea mol­ecules and one Cl atom coordinate the Zn atom in a tetrahedral arrangement. The crystal packing is mainly determined by weak N—H⋯Cl hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C15H11ClN2S, has been prepared by the reaction of Lawesson's reagent with N-(2-chloro­benzoyl)- N′-(4-methyl­benzoyl)­hydrazine, under microwave irradiation and in the absence of solvent. It crystallizes with two mol­ecules per asymmetric unit and X-ray analysis reveals that the three rings in both mol­ecules are nearly coplanar. The mol­ecules form stacks, in a head-to-tail manner, with intermolecular π–π interactions. Intermolecular C—H⋯N hydrogen bonds are also present. [ABSTRACT FROM AUTHOR]

The title complex, C6H15N4O2+·C4H3O4−·2H2O, contains a planar ring formed by sharing one H atom between the O atoms in the carboxyl groups of the maleate anion. This hydrogen bond is slightly asymmetric. In thel-argininium(+) cation, both the α-amino and the guanidyl groups are protonated. The nonlinear optical response of the compound is derived from the intrinsic hyperpolarizabilities of thel-argininium cations, maleate anions and intermolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, {[K2Ni(C5O5)2(H2O)2]·4H2O} n, the Ni atom lies on an inversion centre. Two inversion-related croconate [4,5-dihydroxy-4-cyclo­pentene-1,2,3-trionate(2−)] ligands and an NiII ion form a near-planar symmetrical [Ni(C5O5)2]2− moiety. The near-square coordination centre of the moiety is then extended to an octa­hedral core by vertically bonding two water mol­ecules in the [Ni(C5O5)2(H2O)2]2− coordination anion. The crystal structure is characterized by a three-dimensional network, involving strong K⋯O⋯K binding, K⋯O—Ni binding and hydrogen bonding. [ABSTRACT FROM AUTHOR]

In the title complex, (C6H8N)2[Zn(dmit)2] (dmit is 2-thioxo-1,3-dithiole-4,5-dithiol­ate, C3S5), each Zn atom is coordinated by four dmit S atoms that define a distorted tetra­hedral arrangement. The crystal structure is stabilized by C—H⋯S hydrogen bonding and S⋯S contacts. [ABSTRACT FROM AUTHOR]

The title compound, C13H6O4S5, possesses crystallographically imposed mirror symmetry, with the atoms of the C=S group lying on the mirror plane. It is an example of the general formula [ RCO]2(dmit), where R is a furan ring and dmit is 2-thioxo-1,3-dithiole-4,5-dithiol­ate. The components exhibit some polarization of their mol­ecular–electronic structure. The dmit and furan moieties exhibit a high degree of conjugation, as the introduction of C=O connecting the conjugated furan (donor) and dmit (acceptor) rings forms a good conjugated system with high delocalization. A polar three-dimensional framework is built from a combination of inter­molecular contacts, namely S⋯S inter­actions and C—H⋯O hydrogen bonding. The structural characteristics lead to good second-order non-linear optical properties. [ABSTRACT FROM AUTHOR]

The title complex, [Zn(C2H8N2)3][Zn(C4N2S2)2], exists as discrete ions, both of which lie on twofold rotation axes. The [Zn(C2H8N2)3]2+ cation exhibits a slightly distorted octahedral geometry. In the [Zn(C4N2S2)2]2− anion, the ZnII atom is surrounded by two chelating ligands in a distorted tetrahedral geometry. The crystal structure is stabilized by hydrogen bonds of the types N—H⋯N and N—H⋯S. [ABSTRACT FROM AUTHOR]

The title molecule, C26H46O4, has symmetry. The non-H atoms of the octyloxy and methoxymethyl chains are almost coplanar with the benzene ring. There are weak C—H...O hydrogen bonds and C—H...π-ring interactions in the structure. The molecules are loosely packed in the structure. The unit-cell volume is 20% larger than is expected from the empirical rule pertinent to organic compounds, which states that the unit-cell volume (Å3) is approximately equal to the number of non-H atoms in the unit cell multiplied by 18. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title phospho­nium salt, C22H22O2P+·Br−·H2O, the triphenyl­phospho­sphonium group has three P—C bonds to phenyl rings which are equal within experimental error [mean 1.782 (3) Å] The P atom is also attached directly to the C atom of a 1,3-dioxan-2-ylmethyl group with a longer P—C bond of 1.800 (3) Å. The C—C bond of the dioxane ring [1.418 (5) Å] is shorter than the normal bond distance. The asymmetric unit contains two bromide anions on twofold rotation axes to balance the charge of the cation. [ABSTRACT FROM AUTHOR]

The molecules of the title compound, C11H13N3O3, are linked by O—H⋯N and N—H⋯O interactions into a linear hydrogen-bonded chain. [ABSTRACT FROM AUTHOR]