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Chirality is a fundamental feature of a structure, and chiral systems have been widely applied in many fields. This work mainly paid attention to effects of chiral interaction on molecular nonlinear optical (NLO) response. To this aim, D- or L-type alanine (Ala) with right or left handness respectively were added into chiral single-wall carbon nanotube (CNT) in this work. As a result by theoretical calculation, homo-chiral complex, namely, right-handed CNT with (D)-type Ala (or left-handed CNT with (L)-type Ala) would bring little stronger Ala-CNT interaction and larger first-order static hyperpolarizability β tot. In addition, β tot difference arising from charge transfer transition could be tuned by changing length and (or) chirality of CNT. These consequences were meaningful for further exploration of controlling molecular NLO properties by chirality. [Display omitted] • Chiral CNT and Ala were selected to explore chiral interaction on NLO propertiy. • There were different hyperpolarizabilities of homo- or hetero-chiral complexes. • There might be potential application of chiral interaction in controllable NLO. [ABSTRACT FROM AUTHOR]

Abstract Coronene as the smallest molecular approximation of polycyclic aromatic hydrocarbon (PAH) has large π-conjugated orbital. In the present work, under the action the external electric fields (E ext , perpendicular to molecular plane), the geometric structure of Coronene from plane to "bowl" and "curly". Interestingly, there is a redistribution of orbitals in E ext would give rise to significant effect on the NBO charge, which the main negative charge is gradually concentrated in the center-six-membered with the increasing E ext. The distinct charge transfer phenomenon brought about a remarkable nonlinear optical (NLO) property and changed the location of the main aromaticity. Surprisingly, the irregular phenomena of these properties would be happened in same E ext range: 5.00 × 10−2 to 6.00 × 10−2 au, which is respond to the structural change. We hope present work can provide a new strategy to design the high-performance electro-optical materials for large π-conjugated centrosymmetric system. Graphical abstract Image 1 Highlights • The geometry of Coronene under E ext is from plane to "bowl" and further to "curly". • Redistribution of orbitals in E ext would result in a negative charge that was gradually concentrated in center-six-membered. • The distinct charge transfer phenomenon brought a remarkable NLO property and changed the location of the main aromaticity. [ABSTRACT FROM AUTHOR]

Helical structure was ubiquitous in the nature and many chemists were attracted to synthesize various helicates, to obtain more fantastic functional materials. In this work, we designed pyridine helical ligand with Li 2 doped and explored the effects of redox process on its NLO property. All results stressed the control of redox switch on Li 2 -doped helical complex. In the aspect of geometric structural traits, obtaining or losing electrons made the helix shrank or extended like a coil spring. In the aspect of NLO property, the sharp fluctuation of β tot values with the range of 1.88 × 10 2 to 7.73 × 10 6 au indicated that redox process was an effective switch to control the on-off NLO response. According to the two-level formula, the variation of Δ μ qualitatively explained the change of β tot . In terms of bonding traits, NBO and AIM analyses showed in the redox process, NBO charge transferred along reversed direction for oxidation and reduction process. The results of E 2 and WBIs obtained by population analysis and the properties at Li N BCPs via AIM analysis, including ρ ( r ), ∇ 2 ρ ( r ) and H ( r ) suggested that in the process of obtaining electrons, Li1 N1 bond became weaker while Li1 N3 bond became stronger. All of the results suggested that obtaining or losing electrons was an effective switch to tune the peculiarities of the complex. [ABSTRACT FROM AUTHOR]

Neuronal death after traumatic brain injury (TBI) is a complex process resulting from a combination of factors, many of which are still unknown. Transient receptor potential melastatin 7 (TRPM7) is a transient receptor potential channel that has been demonstrated to mediate ischemic and traumatic neuronal injury in vitro. In the present study, TRPM7 was suppressed in the rat cerebral cortex by intracortical injections of viral vectors bearing shRNA specific for TRPM7 to investigate its potential role in an in vivo TBI model. We found that TRPM7 suppression significantly reduced brain edema, brain contusion volume and motor functional deficits, which was sustained for at least 2 weeks after the insult. These protective effects were accompanied by inhibited apoptosis in injured cortex. Also, TRPM7 suppression attenuated lipid peroxidation, decreased the expression of protein carbonyl, and preserved the endogenous antioxidant enzyme activities. The results of western blot analysis showed that TRPM7 suppression markedly increased the phosphorylation of Akt and endothelial nitric oxide synthase (eNOS). In addition, blocking Akt/eNOS pathway activation by the specific inhibitor LY294002 (LY, 10 μL, 10 mmol/L) or L-NIO (0.5 mg/kg) partially reversed the protective effects of TRPM7 suppression and its anti-oxidative activities. Taken together, these findings demonstrated that regional inhibition of TRPM7 in cerebral cortex exerts neuroprotective effects against TBI through activation of Akt/eNOS pathway. Thus, TRPM7 might represent a potential drug development target for the treatment of TBI. [ABSTRACT FROM AUTHOR]

In 2006, the interesting π-stacks diradical 1,1′-bis(verdazyl)ferrocene ( 2 0 ) with two-electron multicenter (2e/mc) bonding were synthesized and investigated ( J. Am. Chem. Soc. 2006, 128 , 690–691). Based on the 2 0 , two attractive isomeric complexes( 3 19 and 4 144 ) are designed by a piece of radical rotating along iron-Cp axis about 19° and 144°, respectively. Among these three diradicals, a unique two-electron eight-center (2e/8c) π–π bonding is obtained in the 2 0 due to the overlap of SOMOs of the two pieces of radicals, the 3 19 has a σ-covalent bonding, and two separate radicals are shown in the 4 144 . Further, the UV-visible absorption spectrum of 2 0 and 3 19 arise a new absorption feature at 566 and 530 nm, respectively, which may be assigned to π-π stacking ( 2 0 ) and σ-covalent ( 3 19 ) bonding of two pieces of radicals, although this absorption feature not exist in experimental UV-visible absorption spectrum. Fortunately, the UV-visible absorption spectrum of 4 144 is similar to experimental results, which demonstrate that the 2 0 with 2e/8c bonding may transform to be 4 144 with two separate radicals in solution. These three diradicals may transform to each other, which is beneficial to understanding their magnetic properties in solution and crystal and designing new complexes with excellent magnetic property. [ABSTRACT FROM AUTHOR]

[Display omitted] • Based on the π-conjugated DHTPs, four isomers (1 – 4) with D(–NH 2)-π(DHTPs)-A(–NO 2) framework are designed and characterized. • The change of hydrogen position on DHTPs bridge can affect their nonlinear optics (NLO) property. • The change of hydrogen position on DHTPs brings distinctive changes in NICS, NPA charge, UV–vis absorption spectrum, etc. The donor-π-conjugated bridge-acceptor (D-π-A) is a classical framework to design high-performance organic electro-optical materials. In this work, based on the π-conjugated dihydrotetraazapentacenes (DHTPs), four isomers (1 – 4) with D(–NH 2)-π(DHTPs)-A(–NO 2) framework are designed and characterized. The 2 and 3 originate from single-hydrogen migration of 1 , and 4 derives from double-hydrogen migration of 1. Significantly, the change of hydrogen position on DHTPs bridge can affect their nonlinear optics (NLO) property. Compared with the first hyperpolarizability (β tot) (4.08 × 103a.u.) of 1 , the 6.90 × 103-2.56 × 104 a.u. of 2 – 4 are enhanced. More interestingly, the 4 has largest β tot value of 2.56 × 104, which is approximately equal to the sum of 6.90 × 103 a.u. of 2 and 1.82 × 104 a.u. of 3. Furthermore, the change of hydrogen position on DHTPs brings some distinctive changes in their geometric structure, nucleus-independent chemical shifts (NICS) value, natural population analysis (NPA) charge, UV–vis absorption spectrum along with its other electronic property that might be beneficial to explore their structure–property relationships. [ABSTRACT FROM AUTHOR]

A series of Li@BCN models were systematically investigated to explore the physical origin of the interaction between lithium atoms and BCNs. Theoretical results show that the crucial electron population in the BCNs of Li@B-BCN and Li@N-BCN series is dramatically different. As results, the first hyperpolarizability of Li@B-BCN series increases with the increase of carbon proportion whereas that of Li@N-BCN series significantly decreases with the increase of carbon proportion. The results indicate that the physical properties of Li@BCN models are significantly dependent on the different chemical environment of the tube termination. [ABSTRACT FROM AUTHOR]

In the present work, three complexes(1-Li–NO 2 , 1-Li-Mid and 1-Li–NH 2 ) were designed by doping Li atom into the different location(above, middle and below) of the novel noncovalent “through-space” electronic interaction (S) of Donor-S-Acceptor (1) to explore their structure-property relationships. The results show that doping Li atom can obviously enhance the first hyperpolarizability (β tot) of 1. Interestingly, the crucial transition direction of 1-Li–NH 2 is from donor group to acceptor group, which is opposite to those of 1-Li–NO 2 and 1-Li-Mid. The highest occupied molecular orbital (HOMO) of 1-Li–NH 2 shows that doping one Li atom enhances the π–π interaction resulting in the largest β tot value (1.50 × 105) which is about 16 times larger than that of 1(9.13 × 103) and is also obviously larger than those of 1-Li-Mid(5.81 × 104) and 1-Li–NO 2 (6.45 × 104 au). The results indicate that 1-Li–NH 2 can be considered as a novel high-performance NLO material and the location of Li atom can modulate NLO response. [ABSTRACT FROM AUTHOR]

Abstract: The 89 classical C44 isomers, its anions and derivatives such as C44X n (X=H, F, and Cl; n =14 and 16) and M@C44 (M=He, Li, and Ca) have been systematically investigated by ab initio and density function methods. Although the D 2:75 species has the least number of adjacent pentagons, the MP2 geometry optimizations suggest that the D 3 h :72 structure is favored by ∼11kcal/mol over the D 2:75 isomer. Systematic investigations of the electronic properties show that neutral D 3 h :72 is highly aromatic. In contrast, the two lowest energy isomers of , D 2:75 and D 2:89, are highly aromatic. Compared with C50X10 (D 5 h ), the large energy gaps and the aromatic character of C44X14 (D 3 h :72) indicate that they possess high stabilities. Furthermore, the predicted reaction energies of C44X14 (D 3 h :72) derivatives are highly exothermic, suggesting a considerable possibility for experimental realization. Investigations also show that the D 2:75 endohedral structure is most stable for Ca@C44. [Copyright &y& Elsevier]

In this work, the second-order nonlinear optical (NLO) switch features and electron transition properties for a series of donor-acceptor Stenhouse adducts (DASAs) were explored. The systems we studied contain of a given diethylamine donor and different acceptors, which can be photoinduced from open form to closed form. The calculation results show a remarkable difference in the first hyperpolarizability (β) value between two configurations for each of studied systems, revealing a conspicuous NLO switch feature. Interestingly, in the conditions of gas phase, solid phase polarization effects or frequency dispersion effects, the introduction of indandione acceptor demonstrates the most significant NLO switch feature due to the largest β open/ β close ratio of compound 5. In general, the differences in the degree of π-electron conjugation and electron transition property between two configurations are responsible for the contrast of NLO response. Our work reveals the features of NLO switch on structure and electron transition property, which will provide some guidance for designing high performance NLO materials. • The DASA molecules with different acceptors show conspicuous NLO switch feature. • The introduction of indandione acceptor shows the most significant NLO switch feature. • The destruction of π-conjugation between two configurations is responsible for the difference in NLO properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • A systematic impact is studied by electron donating groups for chalcone derivatives. • A dual approach is used to study from molecule level to material level simulations. • Designed chalcones are found more suitable for electron transport than hole transport. • System 3 can transport charge about ~25 times higher as compared to systems 1 and 2. • A comparative analysis of electronic properties is also performed. In this study, three chalcone derivatives with a basic skeleton of [1,100-biphenyl]-4-yl)-3-(3-nitrophenyl)prop-2-en-1-one are investigated. The basic skeleton was modified with the addition of three-terminal groups including hydrogen (1), methyl (2), and methoxy group (3). Using CASTEP Module, the optoelectronic properties are evaluated. The solid-state geometries of these systems are explored within the periodic boundary conditions (PBC). Among these systems, system 3 is found much better in terms of electron transport and optical properties such as dielectric function, absorption, conductivity, reflectivity, loss function, and refractive index. System 3 showed a higher dielectric function value about 3.7 at 1.8 eV thereby absorption 6.9 × 104 cm−1 at 300 nm and conductivity 1.2 fs−1 at 3.5 eV in the (0 0 1) plane. Furthermore, system 3 exhibited a high reflectivity and loss function in the (0 1 0) plane. Electronic band structure, the density of state, and electronic coupling analysis also reveal that system 3 has a potential application in charge transport devices. The study of electronic couplings that dominate the slowest electron hopping in a potential conductive path is roughly four to ten times larger for the holes than for the electrons. The transport pathways in systems 1 and 2 are 2D, while 1D in system 3. The bottleneck rate for electron transport is expected to be ~25 faster for system 3 than the other systems. This system 3 shows an excellent potential both at molecular and bulk levels for efficient charge transport material. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new hybrid model (BNC-n) are designed by the increasing vertical carbon-segment doping into the BN nanosheet. • The first hyperpolaizability of isoelectronic are increased with the increase of the doping carbon-segment. • With the increase of the vertical carbon-segment, the polarizability of isoelectronic gradually increase. Due to wide applications in optoelectronic field, carbon-boron-nitride materials have attracted considerable interest from scientists. In the present work, the structures and first hyperpolarizility (β tot) of three closed shell isoelectronic structures BNC-n (n = 1–3) were investigated, in which BNC-n are designed by the increasing vertical carbon-segment doping into the BN nanosheet. Results show the β tot value of isoelectronic are increased with the increase of the doping carbon-segment. Among these isoelectronic structures, the β tot value (2.80 × 104 au) of BNC-3 is larger (19 times) than the 1.51 × 103 au of BNC-1. Correspondingly, the BNC-3 has the smallest transition energy (1.455 eV), which is obviously smaller than 3.884 eV of BNC-1. We hope the present work is beneficial for scientists to understand and design high performance nonlinear optical materials on carbon-boron-nitride hetero-materials. [ABSTRACT FROM AUTHOR]

Molecular machines were attractive for scientists due to their excellent dynamical properties and potential applications. Inspired by the feature of molecular machine, we designed an ideal unscrewing process of double-chain sexipyridine complex with four conformations and explored the variation of stability and optical properties. As a result, we found the double helices where the fragments bound by only weak π-π interaction had poor stability. Thus the conformation with stronger π-π interaction was more stable than others. But this could be changed by adding alkali metals, and different alkali metal atoms such as Li and Na could control the stability order because of their different atomic radii. For Li-doped molecules, Li-1 with tightly coiled strands was the most stable conformation. While for Na-doped molecules, Na-4 with unscrewed fragments was the most stable one. This mainly resulted from the intra-molecular interaction potential energy especially the interaction between metal and ligand. At the same time, the charge distribution showed corresponding variation. In the aspect of optical properties, the unscrewing process was followed by the variation of absorption intensity at about 500 nm in the UV–Vis absorption spectra because of the conformation change. Meanwhile, the first-order static hyperpolarizability (β tot) showed zigzag variation due to the change of frontier molecular orbital energy gap in the unscrewing process. Image 1 • Double-strand pyridine helix was designed with different conformation. • The stability order of isomers related to the sizes of introduced Li and Na. • NLO property showed zigzag curve in the unscrewing process. • New peak appeared in UV–Vis absorption spectra in the unscrewing process. [ABSTRACT FROM AUTHOR]

Miyoshi myopathy (MM) is an autosomal recessive distal muscular dystrophy caused by mutations in the dysferlin gene ( DYSF ), a 150-kb gene on chromosome 2p13 that contains 55 coding exons. Many patients with MM harbour mutations in the DYSF gene, and most of these mutations are inherited from the patients’ parents. Recently, we encountered novel, de novo mutations in the DYSF gene in a patient with MM. DYSF gene analysis was performed by targeted next-generation sequencing, and we found that the patient had compound heterozygous mutations, including a de novo mutation (c.613C > T) in exon 6 and a novel missense mutation (c.968T > C) in exon 11. The novel missense mutation, predicted to be a disease-causing mutation or affecting protein function by MutationTaster and Polyphen2, confirmed the diagnosis. These findings provide important insights into the pathogenesis and inheritance of MM. [ABSTRACT FROM AUTHOR]

It is well known that settling transparency-efficiency tradeoff is important to design nonlinear optical (NLO) materials. In this work, we constructed one-dimensional polymeric cyanoacetylene (N C C C H) n by hydrogen-bond-directed-linking to understand this tradeoff from molecular level. Results show that the first hyperpolarizability of (N C C C H) n ( n = 2–8) gradually increased with the increase of n , and what is more important is that the red-shifts, associated with the increase of n , were very little. It is proposed that these polymeric structures possess double-degenerated charge transitions, which contribute to the hyperpolarizability in an additive fashion, and that the coupled oscillators are gradually improved, which lead to the increase of the first hyperpolarizability. Therefore, we propose the hydrogen-bond-directed-linking idea is helpful to develop the potential high-performance NLO materials. [ABSTRACT FROM AUTHOR]

Highlights: [•] Three helical complexes are designed to study structure–properties relationship. [•] The Na atom possesses an appropriate size to fit in the helical cavities. [•] The Py–pym–2Na has the smallest interaction energy. [•] The α 0 values improve with increasing the atomic number. [•] The Py–pym–2Na has the largest β 0 value among three helical complexes. [Copyright &y& Elsevier]

Singlet fission (SF) process has attracted growing attention because of its potential capability to overcome the Shockley−Queisser limit on solar cells. So the raising of new molecule with SF character is crucial for its widespread application. In this work, the structure-property relationships of series of boron and nitrogen para-substituted (para- BN-BN and para- BN-NB) anthracene (A-n and A′-n), tetracene (T-n and T′-n), pentacene (P-n and P′-n) and hexacene (H-n and H′-n) are studied to propose novel strategy of designing SF molecule. Among these structures, the number (n) of central rings between para-(BN) 2 -substituted six-membered rings can efficiently adjust the area of aromaticity, the diradical characters, which provide the low-lying T1-state energy and further favoring the availability of efficient SF molecules. We hope present work can provide novel design strategies toward the discovery of bright SF chromophores for the application to efficient organic solar cells. • The structure-property relationships of series of boron and nitrogen para-substituted (para- BN-BN and para- BN-NB) acenes are studied to propose novel strategy of designing SF molecule. • Among these structures, the number (n) of central rings between para-(BN) 2 -substituted six-membered rings can provide the low-lying T1-state and further favoring the availability of efficient SF molecules. • We hope present work can provide novel design strategies toward the discovery of bright SF chromophores. [ABSTRACT FROM AUTHOR]

The forming of catalyst supports is a crucial step in the application of industrial catalysts. Alumina, a widely employed catalyst support, is often shaped using nitric acid as a peptizer to enhance mechanical strength. However, the use of large amounts of nitric acid typically results in a decrease in specific surface area and damage to the pore structure due to chemical corrosion. In this work, we present a more practical approach that is pre-filling the open pores of pseudo-boehmite powder with water instead of directly filling them with nitric acid solution. The binder with a small quantity of nitric acid plays a synergistic role in functioning as a glue on the particle surfaces. And through this method, high-strength (231 N cm−1) alumina support can be prepared more efficiently through extrusion. Besides, the pore structure of the extrudates was characterized by multi-scale methods, including nitrogen physical sorption and XRM (X-ray microscopy), which revealed abundant interconnected hierarchical pores deriving from the pre-wetting shaping process. This proposed approach enables the attainment of high mechanical strength and interconnected porosity for alumina extrudates with less use of acid, which holds a significant practical application value. [Display omitted] • A high-performance alumina extrudate was prepared by a pre-wetting method. • The mechanical strength and water absorption of alumina extrudates were improved. • The pre-wetting method significantly reduced the amount of acid used. • Multi-scale visual characterizations revealed abundant interconnected pores in the alumina extrudates. [ABSTRACT FROM AUTHOR]

This work selected the planar molecule hexabenzo [a,c,k,m,u,w]trinaphthylene (HBTN) with electron donor and acceptor, and introduced static electric field perpendicular to the conjugation plane for its control over molecular physical properties. With the guidance of electron donor and acceptor, controllable chirality, charge polarization, obvious charge transfer transition, Cotton effect and large NLO coefficients of molecule were obtained. The necessity of substituents to realize the control of static electric field to molecular chirality and optical properties was further confirmed by their locations and species. The direction of static electric field was also tested, and the importance of perpendicular field component was stressed. At last, the conclusion obtained via the discussion of monomer could also be applied to both homodimer and heterodimer, where same or different fragments were stacked via π-π interaction respectively. Especially for heterodimer, the completely different optical properties such as UV–Vis absorption spectra, ECD spectra and NLO coefficients between P - and M -type conformations were observed, and made it easier to recognize the chirality of heterodimer. All above results were meaningful to promote the application of molecules as chiral photovoltaic devices. [Display omitted] • Static electric field and substituents synergistically control molecular chirality. • The synergistic effect could be applied to monomer, homodimer and heterodimer. • There were different optical properties between P - and M-type heterodimers. [ABSTRACT FROM AUTHOR]

The benzimidazole-based derivatives 2a-c were designed and synthesized via C–N coupling reaction and experimentally characterized by infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H NMR) spectroscopy and mass spectrometry (MS). The observed and calculated FT-IR frequencies correspond to C O stretching of amide group are depicted at 1657, 1672 and 1682, 1689 and 1699, 1682 for 2a , 2b and 2c respectively and are in good agreement. The synthesized compounds 2a-c exhibit non-linear optical response with the first hyperpolarizability (β 0) at 783, 1550 and 694 au, respectively. Due to the presence of electron withdrawing –NO 2 on the primary amine of 2b , the β 0 value is estimated at 1550 au, which reduces the energy barrier hence increasing the β 0 value, with maximum UV–vis absorption at 224 nm with TD-DFT method. The opposite behavior is demonstrated by the electron donor –OCH 3 substituent. This study of NLO responses would be beneficial to the development of high-performance NLO materials. Three novel benzimidazole-based derivatives were designed and synthesized, which shows enhanced NLO responses and larger excitations with different electron donating/withdrawing groups substitution. Image 1 • Three novel benzimidazole-based derivatives 2a , 2b and 2c were characterized by FT-IR, 1H NMR and mass spectrometry (MS). • The synthesized compounds 2a-c exhibit non-linear optical response with β 0 values at 783, 1550 and 694 au, respectively. • The electron donating/withdrawing effects were studied through three different substituents i.e., –CH 3 , –OCH 3 and –NO 2. • The TD-DFT studies reveal that 2b with –NO2 substitution exhibit obvious red shift with UV–vis absorption at 224 nm. [ABSTRACT FROM AUTHOR]

Recently, the structure-property relationships of an attractive isomeric radical 1 ( Phys. Chem. Chem. Phys. , 2016, 18, 29041–29044) with famous phenalenyl ( PLY ) was investigated. Can PLY and 1 form stable π-dimers? The single point energy scan result shows that the staggered π-dimer ( 2 ) has the lowest energy. In order to explore intermolecular charge-transfer and nonlinear optical property, two π-dimers ( 2a and 2b by boron and nitrogen atoms substituting the central carbon atoms of 2 ) are designed. 2 has smaller intermolecular charge-transfer (0.020) and the first hyperpolarizability ( β tot , 3.18 × 10 2 au). However, boron and nitrogen substitution effect can greatly enhance intermolecular charge-transfer (0.215 for 2a and 0.181 for 2b ) and the β tot values (6.32 × 10 3 for 2a and 6.80 × 10 3 for 2b ). Interestingly, the β tot values of 2a and 2b are close to each other, but their β z components and the NBO charge analysis show that 2a and 2b have opposite direction of charge transfer, which can be well explained by the difference of the dipole moment component (Δ μ z ) between the ground and the excited states. Further, the first hyperpolarizability density study clearly substantiates the difference in their β zzz values: negative contribution for 2a is much larger than positive contribution, while the first hyperpolarizability density for 2b shows much larger positive contribution. Thus, the primary component of β zzz is negative value for 2a and β zzz is positive value for 2b . Combining with the frontier molecular orbital (FMO) and the electron density difference map (EDDM), intermolecular charge-transfer transition from B substituted fragment to N substituted fragment for 2a and 2b is concluded. The significant structure-property relationships in present π-dimers are beneficial for further theoretical and experimental investigations of high-performance nonlinear optical materials. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) and second-order Møller–Plesset theory (MP2) have been employed to investigate CO 2 inserting into C H bond, where CO 2 is in the form of an anion CO 2 − . The reaction begins with CO 2 fixing on the pyrrole to produce ion-complex I via C C bond formation between the carbon atom of pyrrole and the carbon atom of CO 2 . Subsequent re-aromatization by dehydrogenation or hydrogen migration, furnishes electron-molecule compounds III , which release the excess electron to produce pyrrole-carboxylic acid. The C H bond activation and the formation of an extended π-orbital network play important roles in the re-aromatization process. [ABSTRACT FROM AUTHOR]

• FeN 2 -GN, CoN 2 -GN and NiN 2 -GN are designed and explored as eNRR catalysts. • CoN 2 -GN is investigated as the most promising candidate. • The improvement of the catalytic activity of CoN 2 -GN can be contributed to its confinement effects and appropriate space. • The curvature of the junctions helps the promotion of the selectivity of eNRR, where the 'neck' C atoms act as the H-activator to N 2. Exploring efficient and highly selective ammonia synthesis electrocatalysts can advance the development of both modern agriculture and industry. Graphene nanobuds (GN) feature both fullerene and graphene characteristics which inspires new design ideas of electrocatalysts for N 2 reduction reaction (NRR) to ammonia based on the novel GN with traditional Fe-, Co-, Ni-N 2 sites. Among these structures, CoN 2 -GN is investigated as the most promising candidate with a limiting potential of -0.83 V through a distal pathway. The excellent activity and selectivity for the eNRR can be attributed to synergistic effects originated from both confinement space of buds (fullerene fragment) and curvature of the junctions. Especially, acting as an H-activator to N 2 , the 'neck' C atoms in the GNs improve the selectivity significantly for eNRR and facilitate the subsequent processes. This research would greatly contribute to develop the novel, efficient, multi-component graphene-based eNRR catalysts. First principles calculations show that Co-N 2 sites incorporating on the graphene nanobuds (CoN 2 -GN) could act as a promising eNRR catalyst on account of synergistic effects from confinement and curvature of the junctions, where the 'neck' C atoms can act as H-activators to N 2. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Core–shell structured ZnO/In2O3 composites were successfully synthesized via situ growth method. Phase structure, morphology, microstructure and property of the products were investigated by X-ray diffraction (XRD), TG-DTA, field emission scanning electron microscopy (FESEM), energy-dispersive spectrometry (EDS), transmission electron microscope (TEM) and photoluminescence (PL). Results show that the core–shell structures consist of spindle-like ZnO with about 800nm in length and 200nm in diameter, and In2O3 particles with a diameter of 50nm coated on the surface of ZnO uniformly. HMTA plays an important role in the formation of core–shell structures and the addition of In2O3 has a great effect on PL spectrum. Possible mechanism for the formation of core–shell structures is also proposed in this paper. [Copyright &y& Elsevier]

Abstract: The structures of sandwich-like and chain-like superatom compounds Li3–N4–M3 (M=Li, Na and K) are obtained at the MP2/6-311+G(2d) level. These structures are stable own to large interaction energy ranging from −184.4 to −236.9kcal/mol. Maximum nucleus-independent chemical shift (NICSmax) values of M3 + are located at the outside of the M3 + ring plane about 0.6–1.5Å for the sandwich-like structures, which exhibit unusual out-of-plane σ-aromaticity. The NICSmax values of N4 2− in the sandwich-like structures are obviously larger than that of corresponding chain-like structures, which show that the two adjacent rings (Li3 + and M3 +) enhance the aromaticity of N4 2− ring in the sandwich-like structures. In addition, the N4 in the superatom compound is proposed as a new “supersulfur” atom. [Copyright &y& Elsevier]