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On the basis of theoretical models and calculations, CN‐substituted difuropyrene systems have been investigated as potential singlet fission (SF) candidates for solar cell applications. Calculations indicate that the fusion of difuran and pyrene in different arrangements could introduce variable diradical properties, and the fused compound ab‐trans‐DFP has moderate diradical character (y0=0.45) while satisfying the main condition (ΔE1) of SF. Furthermore, CN‐substituted ab‐trans‐DFP (substituted at distinct positions) is used to adjust the frontier molecular orbital energy level to satisfy the SF secondary condition (ΔE2). Interestingly, the position of the cyano substituents has almost no effect on the diradical character, which can be explained by the insensitivity of the ring aromaticity to the cyano position. Both time dependent density functional theory (TD‐DFT) and multi‐configurational self‐consistent field (MCSCF) results confirm that the 4‐ and 5‐position cyano‐substituted ab‐trans‐DFP derivatives can satisfy the two energy conditions and may become potential SF candidates. This work provides an effective strategy for the rational design of new suitable diradical SF candidates, and it is expected that more polycyclic aromatic hydrocarbons such as pyrene can achieve SF conditions by chemical modification, such as fusion or substitution, to adjust the diradical character and the vertical excitation energy. [ABSTRACT FROM AUTHOR]

Structure of (M+@C 50 N 5 H 5)Mʹ−(M = Li and Na; Mʹ = Li, Na, and K) with alkalides characteristics and large nonlinear optical response. [Display omitted] • In this work, a novel type of compound (M+@C 50 N 5 H 5)Mʹ−(M = Li and Na; Mʹ = Li, Na, and K) was designed. • Their alkalides' properties are confirmed by their FMO and NPA charges analysis. • The proposed alkalides exhibited considerable first hyperpolarizability up to 1.91 × 105 a.u. Based on open-cage fullerenes C 50 N 5 H 5 , a novel type of compounds (M+@C 50 N 5 H 5)Mʹ− (M = Li, Na; Mʹ = Li, Na and K) was designed and studied. Firstly, their alkalides' properties are confirmed by their FMO and NPA charges analysis. In particular, the proposed alkalides exhibited considerable first hyperpolarizability (β 0) up to 1.91 × 105 a.u., which indicated that they could be regarded as high-performance novel NLO molecules. These alkalides will pave the way for further exploration of electronic-stable, high-performance NLO materials. [ABSTRACT FROM AUTHOR]

Co-TBSC/MWCNTs (1:2) was successfully prepared by mixing Co-TBSC and MWCNTs in a ratio of 1:2 and used for electrochemical detection of rutin. The preparations of Mn-TBSC/MWCNTs (1:2) and Zn-TBSC/MWCNTs (1:2) were the same. [Display omitted] • Three composite materials were prepared by mixing carbon materials with three crystal materials as electrochemical sensors. • A possible route for the catalytic oxidation of rutin using composite materials was proposed. • An explanation for different sensitivities resulted form different crystal structures was discussed in details. In this study, three sulfonylcalix[4]arene complexes of [Co 2 TBSC(en) 3 ]·2CH 3 OH (Co-TBSC), [Mn 2 TBSC(DMA) 2 (en) 2 ] (Mn-TBSC) and [Zn 2 TBSC(en) 2 ] (Zn-TBSC) were synthesized by solvothermal method with sulfonylcalix[4]arene and three different metal salts. Then multi-walled carbon nanotubes (MWCNTs) was introduced into complexes to form composites of Co-TBSC/MWCNTs(1:2), Mn-TBSC/MWCNTs(1:2) and Zn-TBSC/MWCNTs(1:2), respectively. Various physical characterizations illustrated the successful preparation of three composites. The electrochemical properties of the composites were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results show that they have good electrocatalytic activity and conductivity. The sensors based on the three composites were applied to determine the rutin under the optimal experimental conditions. The results showed that the detection ranges and limits of detection of three kinds of composites for detecting rutin were similar, but the sensitivities of Co-TBSC/MWCNTs(1:2) and Zn-TBSC/MWCNTs(1:2) (9.43 and 9.30 μA·μM−1) are larger than that of Mn-TBSC/MWCNTs(1:2) (5.34 μA·μM−1). Since the three composites were all obtained by mixing three complexes with MWCNTs in a mass ratio of 1:2, the different detection sensitivities may be caused by the different crystal structures of the complexes. The conclusion was further proved by density functional theory (DFT) calculation. [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]

Factors associated with short circuit current density ( J sc ) and open circuit photovoltage ( V oc ) of dye sensitized solar cells (DSSCs) have been analyzed through DFT and TDDFT calculations to explore the origin of the significant performance differences with only tiny structure difference (1.24% for 1 and 8.21% for 2 ) (Advanced Functional Materials 2012, 22, 1291–1302). Our results reveal that the insertion of phenyl ring in 2 enlarges the distance between the dye cation hole and the semiconductor surface and makes the benzothiadiazole (BTDA) unit, which has strong interaction with the electrolyte, far away from the semiconductor, resulting in a decreased charge recombination rate compared with that of 1 . However, the insertion of phenyl ring also results in a distortion of the molecular structure, leading to a decreased light harvesting ability. Hence, two dyes ( 6 and 7 ) derived from 2 with better conjugation degree, farther position of BTDA unit and longer molecular length have been designed to keep the advantages and overcome the disadvantages of 2 simultaneously. The results demonstrate that we get the desired properties of dyes through reasonable molecular design, and these two dyes could be promising candidates in DSSC field and further improve the performance of the cell. [ABSTRACT FROM AUTHOR]

A sulfur-containing MOF-based electrochemical sensor was rationally designed and used for super-sensitive electrochemical capture and detection of multiple heavy metal ions. [Display omitted] • A new sulfur-containing nano-capsule-based MOF Co-TMC4R-BDC was designed. • The metal···S and cation··· π interactions favored the efficient capture of HMIs. • Co-TMC4R-BDC/GCE featured excellent sensing performance for HMIs. • This work developed a synergetic strategy for the capture and detection of HMIs. Development of an effective way for super-sensitive capture and sensing of heavy metal ions (HMIs) is a great challenge because they are extremely toxic to public health and environment. Herein, a new sulfur-containing nano-capsule-based electrochemical metal–organic framework (MOF) sensor [Co 2 (TMC4R)(1,4-BDC) 2 (μ 2 -H 2 O)]·3DMF·CH 3 OH·5CH 3 CN·H 2 O (Co-TMC4R- BDC) was designed for capture and detection of HMIs in aqueous solutions (TMC4R = tetra(4-mercaptopyridine)calix[4]resorcinarene, 1,4-BDC = 1,4-benzenedicarboxylic acid and DMF = N , N '-dimethylformamide). Remarkably, the designed MOF sensors exhibited excellent capture and detection performances for HMIs under the optimal experimental condition. The wide linear ranges of 0.05–12.0, 0.05–13.0, 0.1–17.0 and 0.75–18.0 μM are obtained for Cu2+, Pb2+, Cd2+ and Hg2+, respectively. The corresponding limit of detection (LOD) values are 13, 11, 26, and 18 nM, respectively. Particularly, the LOD values for Cu2+, Pb2+ and Cd2+ are lower than the standard drinking water ones from the World Health Organization. X-ray photoelectron spectroscopy (XPS) confirmed that the exposed S atoms of the nano-capsule units effectively captured HMIs through the complexation between S atoms and HMIs. Further, density functional theory (DFT) calculations indicated the presence of cation··· π interactions between phenyl rings and HMIs. Thereby, the synergistic effects accomplished the effective capture and sensitive detection of HMIs. This work provides a feasible strategy for the capture and electrochemical detection of HMIs in an aqueous solution with the sulfur-containing MOF sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inspired by the the nitrogenase Fe-Mo cofactors, FeMo@GD, FeMo@G-N 6 and FeMo@C 2 N are designed and explored as NRR catalysts. • Among the three catalysts, FeMo@C 2 N exhibits the most superior catalytic activity owing to its low limiting potential (−0.17 V). • FeMo dual-atom NRR catalysts have also been verified to be more efficient by comparing to individual Fe or Mo involved catalysts on account of synergistic effects. Fe-Mo system are recognized as the most successful nitrogenases system towards the synthesis of ammonia. At the same time, Fe or Mo plays a key role in nitrogenase enzymes together with the most common catalyst for nitrogen reduction reaction (NRR). Herein, we designed and explored NRR catalysts of bimetallic Fe-Mo atoms incorporating on three 2D materials, including graphdiyne (GD), Nitrogen atoms substituted graphene (G-N 6) and C 2 N, by means of density functional theory. Fe-Mo atoms supported on C 2 N is calculated to the most promising one owing to its lowest limiting potential (−0.17 V) and excellent selectivity against hydrogen evolution reaction. The superior performance of FeMo dual-atom NRR catalysts has also been verified by comparing to individual Fe or Mo involved catalysts on account of synergistic effects. Besides, the high NRR activity of FeMo@C 2 N could be ascribed to the high localized electronic states of 3d/4d and 2p orbitals near the Fermi level, providing the Fe-Mo active sites with optimal electronic state. Our studies would further inspire some experimental and theoretical researchers to find out the efficient catalysts with high activity for the synthesis of ammonia at room temperature. [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: Spindle-like ZnO nanostructures were successfully synthesized through direct precipitation of zinc acetate aqueous solution at 60°C. Phase structure, morphology and microstructure of the products were investigated by X-ray diffraction, TG-DTA, FTIR and field emission scanning electron microscopy (FESEM). Result showed that hexagonal wurtzite structure ZnO nanostructures with about 100nm in diameter and 100–200nm in length were obtained. HMTA acted as a soft template in the process and played an important role in the formation of spindle-like ZnO nanostructures. Meanwhile, different morphologies were also obtained by altering synthetic temperature, additional agents and the ratios of Zn2+/OH−. Possible mechanism for the variations of morphology with synthesis parameters was also discussed in this paper. [ABSTRACT FROM AUTHOR]

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]

In the present study, three different substituted-polynitrogen heterocyclic ligands, Hatzpa (Hatzpa = 3-(5-Amino-tetrazol-1-yl)-propionic acid), Hpytzipa (Hpytzipa = 2-(5-Pyridin-3-yl-tetrazol-2-yl)-propionic acid), Hphtz (Hphtz = 4-(4-hydroxyphenyl)-1,2,4-triazole) have been chosen to react with CuCl 2 ·2H 2 O, resulting in the formation of three new compounds [Cu(atzpa) 2 ] (1), [Cu(pytzipa) 2 ] (2) and [Cu 4 (Hphtz) 8 ](ClO 4) 4 ·4H 2 O (3). Complex 1 displays a complex 2D structure; complex 2 shows a 2D layer network; complex 3 shows a tetranuclear Cu(II) structure. These compounds show considerable cytotoxicity towards human cervical cancer cells (HeLa). The MTT assay suggests that compound 2 with lowest half maximum inhibitory concentration (IC 50) is the most cytotoxic, compared with compounds 1 and 3. In addition, the cytotoxicity was also confirmed by DAPI fluorescent staining method. The migration of HeLa cells is inhibited by NPs of the three compounds. The results show that complex 1 – 3 NPs can inhibit cell proliferation and migration in vitro. [Display omitted] • Three new Cu(II) coordination polymers have been prepared, namely [Cu(atzpa) 2 ] (1), [Cu(pytzipa) 2 ] (2) and [Cu 4 (Hphtz) 8 ](ClO 4) 4 ·4H 2 O (3). • Complex 1 displays a complex 2D structure; complex 2 shows a 2D layer network; complex 3 shows a tetranuclear Cu(II) structure. • These compounds show considerable cytotoxicity towards human cervical cancer cells (HeLa). • The complexes 1 – 3 NPs can inhibit cell proliferation and migration in vitro. Three different substituted multi-nitrogen heterocyclic ligands, Hatzpa (Hatzpa = 3-(5-Amino-tetrazol-1-yl)-propionic acid), Hpytzipa (Hpytzipa = 2-(5-Pyridin-3-yl-tetrazol-2-yl)-propionic acid), Hphtz (Hphtz = 4-(4-hydroxyphenyl)-1,2,4-triazole) have been chosen to react with CuCl 2 ·2H 2 O, resulting in the formation of three new complexes [Cu(atzpa) 2 ] (1), [Cu(pytzipa) 2 ] (2) and [Cu 4 (Hphtz) 8 ](ClO 4) 4 ·4H 2 O (3). The coordination sites of the three ligands are mainly affected by the different substituents of the polynitrogen heterocycle. These complexes have been characterized by elemental analysis, IR and single crystal X-ray diffraction. Complex 1 displays a 2D structure; complex 2 shows a 2D layer network; complex 3 shows a tetranuclear Cu(II) structure. These complexes show considerable cytotoxicity towards human cervical cancer cells (HeLa). The MTT assay suggested that, compared with complexes 1 and 2, complex 3 with lowest half maximum inhibitory concentration (IC 50) is the most cytotoxic. In addition, the cytotoxicity was also confirmed by DAPI fluorescent staining method. The migration of HeLa cells is inhibited by NPs of the three complexes. The results showed that the NPs of complexes 1 – 3 can inhibit cell proliferation and migration in vitro. [ABSTRACT FROM AUTHOR]

Diradical and low-lying first triplet excited-state energy E (T 1) are served as important elements toward tuning singlet fission (SF) efficiency, necessitating a rational and precise design strategy toward their fabrication. Herein, the tunable current density vectors (CDV) strategy is utilized to identify a series of tunable diradicaloid SF switches between dihydro-tetraaza-acenes isomers. Theoretical calculations indicate that the independent local diatropic CDV (ILD-CDV) on the S 0 -state and T 1 -state is the origin of the radical site and transition defect, respectively. Importantly, the diradical parameter y 0 related to ground state is adjusted by tuning the discontinuous diatropic CDV on zigzag edge of the sandwiched rings, while low-lying first triplet excited-state energy E (T 1) depends on the primary charge-transfer related to delocalized CDV region. Our ultimate goal is to emphasize the CDV analysis method that rationalizes the radical and S 0 → T 1 transition site, which provides new application perspectives for precise designing new material in organic electronics. Image 1 • Tunable current density vectors strategy is utilized to identify a series of diradical SF switches between dihydro-tetraaza-acenes isomers. • The CDV is instrumental in locating radical and excluding the S 0.→ T 1 transition site. • The tunable CDV could tune the diradical parameter and the E (T 1) level. [ABSTRACT FROM AUTHOR]

Background: Insect pheromones are highly effective and environmentally friendly, and are widely used in the monitoring and trapping of pests. However, many researchers have found that various factors such as ultraviolet light and temperature in the field environment can accelerate the volatilization of pheromones, thus affecting the actual control effect. In recent years, electrospinning technology has demonstrated remarkable potential in the preparation of sustained carriers. Moreover, the utilization of biodegradable materials in electrospinning presents a promising avenue for the advancement of eco-friendly carriers., Results: In this study, homogeneous and defect-free pheromone carriers were obtained by electrospinning using fully biodegradable polyhydroxybutyrate materials and pheromones of Spodoptera litura. The electrospun fibers with porous structure could continuously release pheromone (the longest can be ≤80 days). They also had low light transmission, hydrophobic protection. More importantly, the pheromone-loaded electrospun fiber carriers showed stable release and good trapping effect in the field. They could trap pests for at least 7 weeks in the field environment without other light stabilizers added., Conclusion: Sustained-release carriers constructed by electrospinning and green materials could improve the efficacy of pheromones and ensure environmental friendliness, and provided a tool for the management of S. litura and other pests and sustainable development of agricultural. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Background: Ovarian serous cystadenocarcinoma (OSC) is the most prevalent histological subtype of ovarian cancer (OV) and presents a serious threat to women's health. Anoikis is an essential component of metastasis, and tumor cells can get beyond it to become viable. The impact of anoikis on OSC, however, has only been the topic of a few studies., Methods: The mRNA sequencing and clinical information of OSC came from The Cancer Genome Atlas Target Genotype-Tissue Expression (TCGA TARGET GTEx) dataset. Anoikis-related genes (ARGs) were collected by Harmonizome and GeneCards websites. Centered on these ARGs, we used unsupervised consensus clustering to explore potential tumor typing and filtered hub ARGs to create a model of predictive signature for OSC patients. Furthermore, we presented clinical specialists with a novel nomogram based on ARGs, revealing the underlying clinical relevance of this signature. Finally, we explored the immune microenvironment among various risk groups., Results: We identified 24 ARGs associated with the prognosis of OSC and classified OSC patients into three subtypes, and the subtype with the best prognosis was more enriched in immune-related pathways. Seven ARGs (ARHGEF7, NOTCH4, CASP2, SKP2, PAK4, LCK, CCDC80) were chosen to establish a risk model and a nomogram that can provide practical clinical decision support. Risk scores were found to be an independent and significant prognostic factor in OSC patients. The CIBERSORTx result revealed an inflammatory microenvironment is different for risk groups, and the proportion of immune infiltrates of Macrophages M1 is negatively correlated with risk score ( r s  = -0.21, P  < 0.05). Ultimately, quantitative reverse transcription polymerase chain reaction (RT-PCR) was utilized to validate the expression of the seven pivotal ARGs., Conclusion: In this study, based on seven ARGs, a risk model and nomogram established can be used for risk stratification and prediction of survival outcomes in patients with OSC, providing a reliable reference for individualized therapy of OSC patients., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Published by Elsevier Ltd.)

Background: Endometriosis, a common gynecological condition, can cause symptoms such as dysmenorrhea, infertility, and abnormal bleeding, which can negatively affect a woman's quality of life. In the current study, the pathophysiological mechanisms of endometriosis are unknown, but this study suggests that endometriosis is associated with dysregulation of the autoimmune system. This study identify hub genes involved in the prevalence, identification and diagnostic value of endometriosis and autoimmune diseases, and explore the central genes and immune infiltrates, the diagnosis of endometriosis provides a new sight of thinking about diagnosis and treatment., Methods and Results: The relevant datasets for endometriosis GSE141549, GSE7305 and autoimmune disease-related genes (AIDGs) were downloaded from online database. Using the "limma" package and WGCNA to screen out the autoimmune disease related genes and endometriosis related genes, the autoimmune disease gene-related differential genes (AID-DEGs) progressive GO, KEGG enrichment analysis, and then using the protein interaction network and Cytoscape software to select hub genes (CXCL12, PECAM1, NGF, CTGF, WNT5A), using the "pROC" package to analyze the hub genes for the diagnostic value of endometriosis. The difference in the importance of hub genes for the diagnosis of endometriosis was analyzed by machine learning random forest, and the combined diagnostic value of hub genes was analyzed by using the Support Vector Machine (SVM) algorithm. The eutopic (EU) and ectopic endometrium (EC) immune microenvironment of endometriosis was evaluated using CIBERSORT, the correlation of hub genes to the immune microenvironment was analyzed., Conclusion: The hub genes associated with AIDGs are differentially expressed in EC and EU of endometriosis and possess important value for the diagnosis of endometriosis. The hub genes have a very important impact on the immune microenvironment of endometriosis, which is important for exploring the connection between endometriosis and autoimmune diseases and provides a new insight for the subsequent study of immunotherapy and diagnosis of endometriosis., Competing Interests: The authors affirm that there were no financial or commercial ties that might be considered to be a potential conflict of interest for this work., (© 2023 Yang et al.)

Endohedral open-cage fullerenes are one of the attractive types of fullerenes due to their interesting electronic properties which make it potentially promising for applications in molecular electronics. In this paper, a novel structure of Na + ···Cl - @C 50 N 5 H 5 with Na + inside the cavity and Cl - at the opening of the open-cage fullerene is designed to explore the chemical bonding and interaction between the open-cage fullerene system C 50 N 5 H 5 and NaCl salt. Further, the directional migration of Na + was achieved by applying an external electric field (EEF) along the X -axis. Notably, when the EEF ranges from -85 to -86 × 10 -4 au, Na + sharply approaches Cl - to regain its ionic bonding character. In addition, the Wiberg bond index, electron localization function topological analysis, and interaction energy ( E int ) of the structure under the effect of the EEF also experienced a series of interesting changes. We hope that this work will provide a new strategy for the design of innovative materials for molecular electronics.

Objective: Ginsenoside Rd (GSRd) displays a variety of pharmacological effects. However, the underlying role in acute lung injury (ALI) is not clear. In this study, the protective effect of GSRd on lipopolysaccharide (LPS)-induced ALI is investigated to explore the potential mechanisms., Methods: GSRd-target-ALI-related gene set was constructed. And bioinformatics tools were used to discover the potential mechanism. We observed the survival of subjects for 72 h. In addition, male BALB/c mice were intraperitoneal injected with GSRd (25 and 50 mg/kg) after received one intratracheal instillation of LPS. Inflammatory changes, oxidative stress, and phosphorylation were assessed to study the biological effects., Results: A total of 245 interaction genes were collected. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were enriched in immune-inflammatory system. Among them, PI3K-Akt signaling pathway was the highest-ranked pathway of inflammatory response. In vivo study, it was found that GSRd improved survival in endotoxemic mice and inhibited the major characteristic of ALI. And the p-PI3K and p-Akt expression was significantly decreased by GSRd treatment., Conclusion: GSRd could protect mice against LPS-induced ALI effectively by inhibiting the PI3K-Akt signaling pathway., Competing Interests: None of the authors have any conflicts of interest to declare., (Copyright © 2021 by the Shock Society.)

Phenalenyl (PLY) and its derivatives could form one-dimensional π-aggregates through pancake π-π bonding, which would lead to exotic optoelectronic properties. We will highlight the key aspects of the PLY derivatives from the design strategies to exploration of the electronic properties. Here, we primarily construct alternating boron (B)- and nitrogen (N)-doped PLY π-aggregates: dimer[12], trimer[12-1], trimer[12-2], tetramer[12] 2 , pentamer[12] 2 -1, pentamer[12] 2 -2, and hexamer[12] 3 . The geometric and electronic structures show that the short intermolecular distances of the π-aggregates drive the formation of pancake π-π bonding. Significantly, the molecular structures show periodic changes in the π-aggregates, but the first hyperpolarizabilities ( β tot ) present unexpected changes, which are found to increase sharply with increasing even layer thickness due to intermolecular charge transfer. The β tot value of hexamer[12] 3 (5.72 × 10 4 a.u.) is 6.4 times that of tetramer[12] 2 (8.95 × 10 3 a.u.), and is 22.4 times that of dimer[12] (2.55 × 10 3 a.u.). Thus, constructing π-aggregates can significantly improve the second-order NLO response, which is mainly due to intermolecular charge transfer through pancake π-π bonding of the interlayers.

The design of artificial receptors with a specific recognition function and enhanced selectivity is highly desirable in the electrochemical sensing field, which can be used for detection of environmental pollutants. In this facet, metal-organic frameworks (MOFs) featured adjustable porosities and specific host-guest recognition properties. Especially, the large hydrophobic cavity formed in the porous MOFs may become a potential artificial receptor. We herein designed a new porous MOF [Zn 2 (L)(IPA)(H 2 O)]·2DMF·2MeOH·3H 2 O ( Zn-L-IPA ) by using a functionalized sulfonylcalix[4]arene ( L 1 ) and isophthalic acid (H 2 IPA) (DMF = N , N '-dimethylformamide). The specific pore size and pore shape of Zn-L-IPA made it efficiently selective for absorption of bisphenol A ( BPA ), bisphenol F ( BPF ), and bisphenol S ( BPS ). Therefore, a rapid, highly selective, and ultrasensitive electrochemical sensing platform Zn-L-IPA@GP/GCE was fabricated by using Zn-L-IPA as a host to recognize and absorb bisphenol guests ( GP = graphite powder, GCE = glassy carbon electrode). Most strikingly, the extremely low detection limits were up to 3.46 and 0.17 nM for BPA and BPF , respectively, using the Zn-L-IPA@GP/GCE electrode. Furthermore, the "recognition and adsorption" mechanism was uncovered by density functional theory with the B3LYP function. This work offered a prospective strategy for selective absorption and detection of harmful bisphenols with the MOF-based porous material.

Background: Zc3h12d is a negative regulator which plays a crucial role in immune modulation. However, the role of zc3h12d in lung adenocarcinoma (LUAD) remains unclear. We aim to explore the prognostic of zc3h12d and investigate the relationship between zc3h12d expression and immune infiltration in LUAD., Methods: TIMER site was used to analyze the expression of zc3h12d in LUAD. The zc3h12d protein levels in patient tissue samples were detected by immunohistochemistry staining assays. Meanwhile, based on UALCAN database and samples' data from our cohort, we explored the relationship of clinicopathological features and zc3h12d expression to determine the clinical effect of zc3h12d in LUAD. Several databases including GEPIA, Kaplan-Meier plotter and our samples' data were used to explore the prognostic value of zc3h12d in LUAD. Cox regression analysis was established to further evaluate the prognostic value of zc3h12d in LUAD. In addition, zc3h12d promoter methylation was analyzed by UALCAN database. Genetic alteration analysis was observed in the cBioPortal web. GO and KEGG analyses were conducted to elucidate the underlying mechanisms. Finally, the correlation between zc3h12d and tumor-infiltrating immune cells in LUAD was investigated by TIMER database. The B cells level was investigated by flow cytometry analysis of peripheral blood from our LUAD cohort., Results: Zc3h12d expression was significantly higher in LUAD, compared with adjacent normal tissues. The clinical data from the UALCAN database demonstrated that zc3h12d expression was closely related with cancer stage and nodal metastasis. However, patient sample detection revealed that zc3h12d expression was closely related to pathological N (p = 0.0431) and grade (p = 0.004). Moreover, low zc3h12d expression was associated with poorer overall survival in LUAD. We analyzed the methylation level of zc3h12d in LUAD and found that the methylation levels of zc3h12d promoter in LUAD were significantly reduced. In addition, zc3h12d genetic alterations, including deep deletion, could be found in LUAD. GO and KEGG pathway analysis results indicated that zc3h12d has a certain value in immune infiltration. We investigated the expression of zc3h12d in tumor-immune interactions. It was found that zc3h12d might be associated with the immune infiltration and markers of infiltrating immune cells of LUAD. The results of patient sample detection confirmed that B cells level was significantly lower in the patients with low zc3h12d expression than those in the patients with high zc3h12d expression., Conclusion: zc3h12d might be considered as a potential biomarker for determining prognosis and immune-related therapeutic target in LUAD., Competing Interests: The authors declare that there are no conflicts of interest., (© 2021 Yang et al.)

The anti-Markovnikov hydroamination reaction is considered to be a particular challenge, and one of the reactants, parent hydrazine, is also regarded as a troubling reagent. In this study, we first studied the hydrohydrazination of parent hydrazine via an effective and green catalyst-external electric field (EEF). The calculation results demonstrated that the anti-Markovnikov and Markovnikov pathways are competitive when there was no catalyst. EEF oriented along the negative direction of the X axis (F x ) accelerated the anti-Markovnikov addition reaction. Moreover, it lowered the barrier height of the first step by 16.0 kcal mol -1 (from 27.8 to 11.8 kcal mol -1 ) when the field strength was 180 (×10 -4 ) au. Under the same conditions, the Markovnikov reaction pathway was inhibited, which means that EEF achieved the specificity of hydrohydrazination. The solvents are favorable for the first step addition reaction, particularly the synergy between solvents and F x lowered the barrier heights by 8.3 (C 6 H 6 ) and 10.7 (DMSO) kcal mol -1 for an F x = -60 (×10 -4 ) au. Besides, the introduction of the electron-withdrawing substituent (trifluoromethyl) is also a good strategy to catalyze hydrohydrazination, while the electron-donating group (methoxy) is unfavorable., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We present a theoretical design of the singlet-fission (SF) interconversion between two hydrogen tautomers to attract attention to electronic devices such as switches in the SF field. We develop a tuned π-electron conjugation strategy based on single-hydrogen migration to introduce diradical character and yield low-lying E (T 1 ) levels. Specifically, these objectives could be accomplished by moving one hydrogen from a dihydrogen-substituted pyrazine-fused ring to another unsubstituted pyrazine-fused ring in tetraazatetracenes. The predicted SF efficiency would be expected to exceed 120%. To guide future SF design development, one rule of thumb regarding the S 0 -state and T 1 -state emerges from our research: In the S 0 -state, single-hydrogen migration is crucial for effectively localized electrons, which are the key factor in the formation of diradicals. Conversely, single-hydrogen migration induces a large area of π-electron conjugation in the T 1 -state, which is completely applied to the electron-hole interaction in the S 0 → T 1 transition, thereby providing low-lying E ( T 1 ) levels. Furthermore, a series of hydrogen tautomers of tetraazaacenes have been proposed as diradicaloid SF switches to verify the reliability of the above rule of thumb. This study will not only help researchers in the photovoltaic field to obtain the desired E ( T 1 ) in the future but also broaden the application of hydrogen migration in photovoltaic switch research and supplement the SF database.

The orientation directions of an external electric field (EEF) in catalyzing chemical reactions are an important factor because they can significantly accelerate reaction activity. In this study, we explored a new anti-Markovnikov hydroboration reaction of C-O unsaturated compounds ( e.g. , benzaldehyde and benzophenone) with the aim of revealing the dominant direction of EEF in accelerating the reactions, and pinacolborane (HBpin) was selected as an efficient reductant. The calculation results showed that the EEF oriented along the direction of electron pair transform rather than that of the molecular dipole moment could reduce the barrier of the hydroboration of benzaldehyde by 20 kcal mol -1 when the EEF was up to 150 × 10 -4 au. Moreover, the Markovnikov hydroboration of aldehyde and ketone was investigated for obtaining the mechanistic-switchover point. Unsatisfactorily, the EEF could just influence the respective barriers without a promising competition with the anti-Markovnikov hydroboration reactions., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In order to study the correlation between the traits of Andrographis paniculata. The main agronomic traits and the content of four kinds of diterpene lactons were measured by the seedlings and the unmutagenized seeds carried by the spacecraft,and multiple comparisons,correlations and principal component analysis were carried out. The results showed that the agronomic traits of A. paniculata have different degrees of difference after being carried by space. The contents of diterpene lactones were quite different. The variation coefficients of deoxyandrographolide content,fresh weight,leaf dry weight,dehydrated andrographolide content,dry weight,neoandrographolide content and andrographolide content were all over 35%. There was a significant correlation between multiple traits,and the leaf weight ratio was significantly positively correlated with the number of primary tillers,leaf dry weight and dry weight,and was significantly negatively correlated with the content of deoxyandrographolide. Andrographolide content was a significantly negatively correlated with the number of leaves and the number of primary tillers,and positively correlated with the other three lactones. Five principal components were extracted from principal component analysis,and the cumulative contribution rate was 83. 127%,which were yield factor,plant type factor,leaf type factor,component factor and seed weight factor. Among the traits affecting the quality of A. paniculata,the yield factor for reliability of the selection of A. paniculata is higher than other factors. There are abundant variations among the traits of A. paniculata,carried in space which increase the genetic diversity. The principal component analysis method can be used to select the principal component factors according to the breeding requirements,which provides a theoretical basis for the breeding of high-yield and high-quality A. paniculata and the high-yield and stable cultivation of A. paniculata.

The nature of the 2e/12c bond and its conversion to a carbon-carbon single bond in phenalenyl dimers have prompted a great deal of interests recently. In this work, we theoretically investigated a series of π-stacking phenalenyl derivatives with 2e/12c bonding character by density functional theory (DFT) calculations to elucidate origin of this unusual bond conversion. Results show that bond-conversion of the phenalenyl dimer easily occurs at room-temperature both dynamically and thermodynamically. However, bond-conversion of hetero π-stacking adducts, in which the two center carbon atoms were substituted by boron and nitrogen atoms, respectively, is much more difficult, because the 2e/12c bond is stabilized by its charge transfer character. Consequently, the bond-conversion is an endothermic process, albeit with a low conversion barrier. Interestingly, Lewis acid-base interactions would be induced by substitution of the center nitrogen atom to phosphorus atom. The 2e/12c bond is further stabilized by 5.9 kcal mol -1 and its conversion is also thermodynamically unfavorable., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Usually, an extra catalyst (for example, the transition metal complexes) need to be used in catalyzing hydroboration, which involved the cost, environment, and so forth. Here, a greener and controllable catalyst-external electric field (EEF) was used to study its effect on hydroboration of N-(4-methylbenzyl)aniline (PhN═CHPhMe) with pinacolboane (HBPin). The results demonstrated that EEF could affect the barrier heights of both two pathways of this reaction. More significantly, flipping the direction of EEF could modify the reaction mechanism to induce a dominant inverse hydroboration at some field strength. That is to say, oriented EEF is a controlling switch for the anti- or Markovnikov hydroboration reaction of imines. This investigation is meaningful for the exploration of greener catalyst for chemistry reaction and guide a new method for the Markovnikov hydroboration addition. © 2019 Wiley Periodicals, Inc., (© 2019 Wiley Periodicals, Inc.)

Alzheimer's disease (AD) represents a progressive neurodegenerative disorder characterized by distinctive neuropathological changes. Recently, long noncoding RNAs (lncRNAs) have become a key area of interest due to their potential in AD therapy. Hence, the aim of the current study was to investigate the effect of lncRNA SOX21-AS1 on neuronal oxidative stress injury in mice with AD via the Wnt signaling pathway by targeting FZD3/5. Microarray analysis was performed to screen AD-related differentially expressed genes (DEGs). Following verification of the target relationship between SOX21-AS1 and FZD3/5, the contents of OH - , malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were determined, with the expressions of SOX21-AS1, FZD3/5, β-catenin, cyclin D1, and 4-HNE in hippocampal neuron cells subsequently detected. Cell cycle distribution and apoptosis were evaluated. Bioinformatics analysis revealed that SOX21-AS1 was upregulated in AD, while highlighting the co-expression of SOX21-AS1 and FZD3/5 genes and their involvement in the Wnt signaling pathway. AD mice exhibited diminished memory and learning ability, increased rates of MDA, OH - , SOX21-AS1, 4-HNE, and elevated levels of hippocampal neuron cell apoptosis, accompanied by decreased levels of SOD, CAT, GSH-Px, FZD3/5, β-catenin, and cyclin D1. Silencing of SOX21-AS1 resulted in decreased OH - , MDA contents, SOX21-AS1, and 4-HNE, and increased SOD, CAT, GSH-Px, FZD3/5, β-catenin, and cyclin D1, as well as reduced apoptosis of hippocampal neuron cells. Taken together, the key findings of the present study demonstrated that silencing of lncRNA SOX21-AS1 could act to alleviate neuronal oxidative stress and suppress neuronal apoptosis in AD mice through the upregulation of FZD3/5 and subsequent activation of the Wnt signaling pathway.

Generally, the hydroboration of benzonitrile produces B-N containing compounds. However, an unprecedented B-C bond may be formed in the presence of a suitable external electric field (EEF). In reactions of benzonitrile with borane, when the EEF is oriented parallel to the positive direction (N → C) of the N[triple bond, length as m-dash]C bond, the barriers to Markovnikov hydroboration are decreased gradually, meaning the pathway for generating B-C bonds becomes more favorable. Accordingly, hydroboration could be influenced and its selectivity could be controlled by changing the magnitude and direction of an applied EEF.

Immunogenic antigen (spinosin-BSA) and coating antigen (spinosin-OVA) of spinosin were synthesized by sodium periodate oxidation method. UV scanning analysis method showed that these two spinosins were successfully conjugated with carrier protein and the coupling ratio was 17 and 13.7, respectively. Meanwhile, when immunized by spinosin-BSA，the mice can produce anti-spinosin antibodies with the high titer (1:32 000),specificity (IC₅₀ 211.6 μg·L⁻¹) and low cross-reaction rate measured by ELISA tests. The artificial antigen of spinosin was successfully synthesized, which can be applied for preparation of monoclonal antibodies and establishment of appropriate immune method., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

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., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Very recently, an unprecedented novel monometallic cluster of fullerenes entrapping a yttrium cyanide (YCN) cluster inside a popular C82 cage YCN@Cs(6)-C82 was synthesized and characterized. Inspired by this investigation, four non-IPR YCN@C1(17459)-C76, YCN@C2v(19138)-C76, YCN@C2(17646)-C76, and YCN@C1(17894)-C76 (1, 2, 3, and 4) containing a pair of adjacent pentagons are designed to explore the encapsulated molecular effect on their interaction energies and nonlinear optical properties. The interaction energy (E int) values of 1, 2, 3, and 4 are -481.35 (1), -477.91 (2), -482.04 (3), -482.69 (4) kcal mol(-1), respectively, which shows that the E int value of 4 is the largest. Furthermore, the electron-transfer is mainly from the YCN to C76 cage. When YCN is encapsulated into C76 cage, we can find that the α0 values of the four molecules are very close, ranging from 6.50 × 10(2) to 6.65 × 10(2) au. Significantly, the first hyperpolarizabilities are in relation to the encapsulated molecular: 1.63 × 10(3) (1) > 8.03 × 10(2) (2) > 7.76 × 10(2) (4) > 4.86 × 10(2) au (3), the results show that the βtot value of 1 is the largest. Besides this, the encapsulation of the YCN to C76 cage brings some distinctive changes in its UV-vis spectra along with its other electronic properties that might be used by the experimentalists to develop the potential nonlinear optical nanomaterials based on endohedral metallofullerenes.

Very recently, two new cage-like radicals (C59B and C59N) formed by a boron or nitrogen atom substituting one carbon atom of C60 were synthesized and characterized. In order to explore the structure-property relationships of combination the cage-like radical and alkali metal, the endohedral Li@C59B and Li@C59N are designed by lithium (Li) atom encapsulated into the cage-like radicals C59B and C59N. Further, the structures, natural bond orbital (NBO) charges, and nonlinear optical (NLO) responses of C59B, C59N, Li@C59B, and Li@C59N were investigated by quantum chemical method. Three density functional methods (BHandHLYP, CAM-B3LYP, and M05-2X) were employed to estimate their first hyperpolarizabilities (β tot) and obtained the same trend in the β tot value. The β tot values by BHandHLYP functional of the pure cage-like radicals C59B (1.30 × 10(3) au) and C59N (1.70 × 10(3) au) are close to each other. Interestingly, when one Li atom encapsulated into the electron-rich radical C59N, the β tot value of the Li@C59N increases to 2.46 × 10(3) au. However, when one Li atom encapsulated into the electron-deficient radical C59B, the β tot value of the Li@C59B sharply decreases to 1.54 × 10(2) au. The natural bond orbital analysis indicates that the encapsulated Li atom leads to an obvious charge transfer and valence electrons distribution plays a significant role in the β tot value. Further, frontier molecular orbital explains that the interesting charge transfer between the encapsulated Li atom and cage-like radicals (C59B and C59N) leads to differences in the β tot value. It is our expectation that this work will provide useful information for the design of high-performance NLO materials.

Recently, the crystal structures and electrochemical properties of the isomers (Sc2S "trapped" in C82) have been reported, in which the Sc2S is located inside the different positions of the C82 cage. In the present work, three isomers of endohedral metallofullerenes Sc2S@C3v(8)-C82 (A, B, and C) have been designed to explore the effect of the position of Sc2S on their interaction energies and nonlinear optical properties. Among three isomers, the Sc2S is located in different positions of the C82 cage: the angles of Sc-S-Sc in A, B, and C are 104.9, 114.8, and 115.7°, respectively. Furthermore, the analysis of natural bond orbital (NBO) charge indicates that the electron-transfer is from the Sc2S to the adjacent carbon atoms of the C82 cage. The interaction energy of B is the smallest among three isomers which is -226.2 kcal mol(-1). It was worth mentioning that their first hyperpolarizabilities (β tot) were studied, we found that their β tot values were related to the positions of Sc2S: C (2100) > B (1191) > A (947 au). We hope that the present work can provide a new strategy to promote the nonlinear optical properties of endohedral metallofullerenes by changing the positions of the encapsulated molecular. Graphical abstract Three isomers of endohedral metallofullerenes Sc2S@C3v(8)-C82 (A, B, and C) have been designed to explore the position effect of Sc2S on the interaction energies and nonlinear optical properties. Among three isomers, the Sc2S in B has the most stable position. Significantly, the first hyperpolarizability is related to the position of Sc2S inside the C82 cage, which provides a novel strategy to enhance the first hyperpolarizability by the Sc2S revolving inside the C82 cage.

Recently, two isomeric thiophene-fused benzocarborane derivatives Tb1 and Tb2 with different locations of sulfur atoms, labeled as 1, 4 and 6, 9 of the thiophene were synthesized by Morisaki (Chem.-Eur. J., 2012, 18, 11251-11257) and Barrere (Macromolecules, 2009, 42, 2981-2987), respectively. In the present work, natural bond orbital (NBO) analysis shows that after doping one lithium atom into the isomeric structures Tb1 and Tb2, the electrons transfer to different regions in Tb1 and Tb2. For Tb1-Li, the transferred electrons mainly locate at S1, C2, C3, and S4, but for Tb2-Li, the transferred electrons mainly locate at C2, C3, C7, and C8. Significantly, the charge distribution is a crucial factor influencing the static first hyperpolarizabilities for Tb1-Li and Tb2-Li. Furthermore, the βtot value of Tb1-Li is 6222 au, which is about 160 times larger than that of Tb1 (39 au). However, the βtot value of Tb2-Li (498 au) is only about 5 times larger than that of the corresponding Tb2 (91 au). It is our expectation that this work could provide useful information for the development of nonlinear optical materials based on carboranes.

An increasing number of chemists have focused on the investigations of two-electron/multicenter bond (2e/mc) that was first introduced to describe the structure of radical dimers. In this work, the dimerization of two isoelectronic radicals, triazaphenalenyl (TAP) and hexaazaphenalenyl (HAP) has been investigated in theory. Results show TAP2 is a stable dimer with stronger 2e/12c bond and larger interaction energy, while HAP2 is a less stable dimer with larger diradical character. Interestingly, the ultraviolet-visible absorption spectra suggest that the dimerization induces a longer wavelength absorption in visible area, which is dependent on the strength of dimerization. Significantly, the amplitude of second hyperpolarizability (γ(yyyy)) of HAP2 is 1.36 × 10(6) a.u. that is larger than 7.79 × 10(4) a.u. of TAP2 because of the larger diradical character of HAP2. Therefore, the results indicate that the strength of radical dimerization can be effectively detected by comparing the magnitude of third order non-linear optical response, which is beneficial for further theoretical and experimental studies on the properties of complexes formed by radical dimerization.

On the basis of the famous staggered biphenalenyl diradical π dimer 1, the eclipsed biphenalenyl (1a), with no centrosymmetry, was obtained by rotating a layer of 1 by 60° around its central axis. Furthermore, the central carbon atoms of 1 and 1a were substituted by boron and nitrogen atoms to form 2 and 2a with a novel 2e-12c bond. We found that the novel 2e-12c bond is formed by the electron pair of the occupied orbital of the phenalenyl monomer substituted by the nitrogen atom and the unoccupied orbital of the phenalenyl monomer substituted by the boron atom. As a result of the novel 2e-12c bond, 2 and 2a exhibit a fascinating interlayer charge-transfer transition character, which results in a significant difference in the dipole moments (Δμ) between the ground state and the crucial excited state. The values of Δμ for 2 and 2a are 6.4315 and 6.9253 Debye, clearly larger than the values of 0 and 0.0015 Debye for 1 and 1a. Significantly, the boron/nitrogen substitution effect can greatly enhance the first hyperpolarizabilities (β(0) ) of 2 and 2a with a novel 2e-12c bond compared with 1 and 1a with a traditional 2e-12c bond: 0 and 19 a.u. for 1 and 1a are much lower than 3516 and 12272 a.u. for 2 and 2a. Furthermore, the interaction energies (E(int) )of 2 and 2a are larger than those of 1 and 1a, which could be considered as a signature of reliability for the newly designed dimers. Our present work will be beneficial for further theoretical and experimental studies on the properties of molecules with the novel 2e-12c bond., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The interesting radical ion pair salts M(2)*(+)TCNQ*(-) (M=Li, Na, K) are a particular class of charge transfer complexes with excess electron. The ground states of these complexes are triplet. The C(2v) symmetry geometrical structures of the M(2)*(+)TCNQ*(-) (M=Li, Na, K) with all-real frequencies are obtained at the density functional theory (DFT) B3LYP/6-31+G(d) level. All calculations of electric properties in this paper have been carried out at the restricted open-shell second order Møller-Plesset perturbation theory (ROMP2) level. Owing to existing excess electron (from the polarized alkali metal atoms) these charge transfer complexes exhibit large nonlinear optical (NLO) responses dominated by excess electron transitions.For these radical ion pair salts M(2)*(+)TCNQ*(-), the static first hyperpolarizabilities (beta(0)) are large. The order of beta(0) values is 19 203 (M=Li)<24 140 (M=Na) < 29 065 a.u. (M=K). Specially, the second hyperpolarizability (gamma(0)) of the complexes with excess electron is obtained for the first time. These static second hyperpolarizabilities are also large. The order of gamma(0) values is 2,213,006 (M=Li)<3,136,754 (M=Na)<7,905,623 a.u. (M = K). Among the three structures, K(2)*(+)TCNQ*(-) has the largest gamma(0) value to be 7.9 x 10(6) a.u. (3982 x 10(-36) esu), which is about 9 times larger than that of the intramolecular charge transfer complex sigma-arylvinylidene trans-[Ru(4-C[double bond, length as m-dash]CHC(6)H(4)C[triple bond, length as m-dash]CC(6)H(4)NO(2))Cl(dppm)(2)]PF(6) [Hurst et al., Organometallics, 2001, 20, 4664]. The present investigation provides a new kind of candidates for the high-performance NLO materials.