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The taxonomic relationship between Streptomyces violarus and Streptomyces violaceus was reevaluated using a polyphasic taxonomic approach in this work. Phylogenetic analysis based on 16S rRNA gene sequences indicated that Streptomyces violarus JCM 4534 T was closely related to Streptomyces arenae ISP 5293 T. However, phylogenetic analysis based on five house-keeping gene (atpD, gyrB, recA, rpoB and trpB) showed that the evolutionary neighbor of Streptomyces violarus JCM 4534 T was Streptomyces violaceus CGMCC 4.1456 T, suggesting that there was a close genetic relationship between these two strains. The average nucleotide identity and digital DNA-DNA hybridization values between them were 97.0 and 72.9%, respectively, greater than the 96.7 and 70% cut-off points recommended for delineating a Streptomyces species. This result indicated that they belonged to the same genomic species which was also verified by a comprehensive comparison of phenotypic and chemotaxonomic characteristics between Streptomyces violarus JCM 4534 T and Streptomyces violaceus CGMCC 4.1456 T. According to all these data and the rule of priority in nomenclature, it is proposed the Streptomyces violarus (Artamonova and Krassilnikov 1960) Pridham 1970 is a later heterotypic synonym of Streptomyces violaceus (Rossi Doria 1891) Waksman 1953. In addition, based on dDDH, Streptomyces violaceus and Streptomyces violarus are simultaneously designated as two different subspecies, i.e., Streptomyces violaceus subsp. violaceus and Streptomyces violaceus subsp. violarus.
Asunto(s)
ADN Bacteriano , Filogenia , ARN Ribosómico 16S , Streptomyces , Streptomyces/genética , Streptomyces/clasificación , ARN Ribosómico 16S/genética , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Hibridación de Ácido Nucleico , Proteínas Bacterianas/genéticaRESUMEN
Photo-driven cross-coupling of o-arylenediamines and alcohols has emerged as an alternative for the synthesis of bio-active benzimidazoles. However, tackling the key problem related to efficient adsorption and activation of both coupling partners over photocatalysts towards activity enhancement remains a challenge. Here, we demonstrate an efficient interface synergy strategy by coupling exposed oxygen vacancies (VO) and Pd Lewis acid sites for benzimidazole and hydrogen (H2) coproduction over Pd-loaded TiO2 nanospheres with the highest photoredox activity compared to previous works so far. The results show that the introduction of VO optimizes the energy band structure and supplies coordinatively unsaturated sites for adsorbing and activating ethanol molecules, affording acetaldehyde active intermediates. Pd acts as a Lewis acid site, enhancing the adsorption of alkaline amine moleculesvia Lewis acid-base pair interactions and driving the condensation process. Furthermore, VO and Pd synergistically promote interfacial charge transfer and separation. This work offers new insightful guidance for the rational design of semiconductor-based photocatalysts with interface synergy at the molecular level towards the high-performance coproduction of renewable fuels and value-added feedstocks.
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Light-driven photoredox catalysis presents a promising approach for the activation and conversion of methane (CH4) into high value-added chemicals under ambient conditions. However, the high C-H bond dissociation energy of CH4 and the absence of well-defined C-H activation sites on catalysts significantly limit the highly efficient conversion of CH4 toward multicarbon (C2+) hydrocarbons, particularly ethylene (C2H4). Herein, we demonstrate a bimetallic design of Ag nanoparticles (NPs) and Pd single atoms (SAs) on ZnO for the cascade conversion of CH4 into C2H4 with the highest production rate compared with previous works. Mechanistic studies reveal that the synergistic effect of Ag NPs and Pd SAs, upon effecting key bond-breaking and -forming events, lowers the overall energy barrier of the activation process of both CH4 and the resulting C2H6, constituting a truly synergistic catalytic system to facilitate the C2H4 generation. This work offers a novel perspective on the advancement of photocatalytic directional CH4 conversion toward high value-added C2+ hydrocarbons through the subtle design of bimetallic cascade catalyst strategy.
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To identify superalkali-alkaline earthide ion pairs, it's theoretically shown that, as a novel class of excess electron superalkali compounds, both chair and boat forms of (AM-HMHC)-AM' (AM = Li, Na, and K; AM' = Be, Mg, and Ca; HMHC = 1,4,7,10,13,16-hexamethyl-1,4,7,10,13,16-hexaazacyclooctadecane) are good candidates. An attractive superalkali-alkaline earthide ion pair in δ+(AM-HMHC)-AM'δ- is firstly exhibited, which possesses alkaline-earthide characteristics and nonlinear optical response superior to similar M+(calix[4]pyrrole)M'- (M = Li, Na, and K; M' = Be, Mg, and Ca) with high stability. The electronic and vibrational second order hyperpolarizabilities and the frequency-dependent first hyperpolarizabilities of δ+(AM-HMHC)-AM'δ- are presented. For each pair of (AM-HMHC)-AM', the boat conformation is preferred to its chair one in the case of Hyper-Rayleigh scattering response (ßHRS). These alkaline earthides suggest prominently high ßHRS up to 2.59 × 104 a.u. (boat forms of δ+(Na-HMHC)-Caδ-). We expect that this work will inspire the preparation and characterization of these new alkaline earthides as high-performance NLO materials.
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Two actinomycete strains, designated MG62T and CRLD-Y-1, were isolated from rhizosphere soil of Koelreuteria paniculata and healthy leaves of Xanthium sibiricum, respectively, in Hunan province, PR China. They could produce abundant aerial mycelia that generated rod-shaped spores with spiny surfaces. Morphological features of the two strains are typical of the genus Streptomyces. Strains MG62T and CRLD-Y-1 exhibited 99.93â% 16S rRNA gene sequence similarity. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between them were 99.99 and 100â%, respectively, suggesting that they belonged to the same species. 16S rRNA gene sequences analysis revealed that the two strains belonged to the genus Streptomyces and showed highest similarities to Streptomyces violarus NBRC 13104T (99.07-99.29â%) and Streptomyces arenae ISP 5293T (99.21-99.35â%). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains MG62T and CRLD-Y-1 were closely related to S. violarus NBRC 13104T and S. arenae ISP 5293T. However, the ANI, dDDH and multilocus sequence analysis evolutionary distance values between the two strains and their relatives provide a robust basis upon which to verify strains MG62T and CRLD-Y-1 as representing a novel species. Moreover, a comprehensive comparison of phenotypic and chemotaxonomic characteristics further confirmed that the two strains were distinct from their relatives. Based on all these data above, strains MG62T and CRLD-Y-1 should represent a novel Streptomyces species, for which the name Streptomyces koelreuteriae sp. nov. is proposed. The type strain is MG62T (=JCM 34747T=MCCC 1K06175T).
Asunto(s)
Streptomyces , Xanthium , Ácidos Grasos/química , Análisis de Secuencia de ADN , Filogenia , Rizosfera , ARN Ribosómico 16S/genética , Microbiología del Suelo , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Vitamina K 2RESUMEN
To provide a novel intramolecular self-redox switch, a boron-based sandwich-like complex Rb3BeB6Be'Rb'3 is achieved by using theoretical computations. An applicable oriented external electric field (OEEF) can result in the occurrence of intramolecular self-redox (IMSR) with a long-range electron transfer from tetrahedral Be'Rb'3 to Rb3Be and subsequently [Rb3Be]3+[B6]6-[Be'Rb'3]3+ (D3d) changes to [Rb3Be]2+[B6]6-[Be'Rb'3]4+ (C3v), accompanying high-performance NLO switchable effect for both static and dynamic first hyperpolarizability (ß0). [Rb3Be]3+[B6]6-[Be'Rb'3]3+ (off-form) owns zero of dipole moment (µ0) and ß0, while [Rb3Be]2+[B6]6-[Be'Rb'3]4+ (on-form) exhibits a µ0 of 3.36 D and a ß0e of 2.18 × 105 au. The different dynamic first hyperpolarizabilities between [Rb3Be]3+[B6]6-[Be'Rb'3]3+ and [Rb3Be]2+[B6]6-[Be'Rb'3]4+ are also significant. This indicates that Rb3BeB6Be'Rb'3 is a potential candidate for an IMSR NLO switch.
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Objective: To investigate the reason for fungal balls (FBs) being localized in paranasal sinuses, we analyzed the clinical presentations of patients with FB rhinosinusitis (FBS). Methods: Clinical data, anatomical variation (ie, nasal septal deviation, concha bullosa, and Haller cell), as well as measurements of nasal resistance (NR), nasal cavity volume (NCV), and nasal cross-sectional area (NCA) using active anterior rhinomanometry and acoustic rhinometry were collected from FBS patients hospitalized in our hospital between January 2021 and December 2022. A retrospective analysis was conducted using IBM SPSS 19.0 to perform the Shapiro-Wilk test, t-test and logistic regression analysis. Results: A total of 95 FBS patients, including 33 male and 62 female patients, were included in this study. FBs in maxillary sinus were the most common (83, 87.4%), followed by sphenoid sinus (9, 9.5%). Logistic multivariate regression analysis revealed that a higher left-to-right NR ratio was associated with an increased likelihood of FBs being present in the left sinus [Odds ratios (OR) = 0.185; 95% CI, 0.061-0.558; P < .01]. When the ratio of the left-to-right second-minimum NCA was higher and the FB was more in the right sinus (OR = 3.194; 95% CI, 1.593-6.405; P = .001). Additionally, when the difference between left and right NCV was greater and FB occurred more commonly in the right sinus (OR = 1.435; 95% CI, 1.196-1.721; P < .001). Nonetheless, the presence of nasal septum deviation and concha bullosa did not significantly contribute to FB formation. Conclusions and significance: The differences in NR, NCA, and NCV between the affected and unaffected sides of nasal cavity are risk factors for the FB formation. To reduce FBS recurrence, it is important to focus on improving nasal ventilation during the surgical treatment.
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Benzimidazoles are a versatile class of scaffolds with important biological activities, whereas their synthesis in a lower-cost and more efficient manner remains a challenge. Here, we demonstrate a conceptually new radical route for the high-performance photoredox coupling of alcohols and diamines to synthesize benzimidazoles along with stoichiometric hydrogen (H2 ) over Pd-decorated ultrathin ZnO nanosheets (Pd/ZnO NSs). The mechanistic study reveals the unique advantage of ZnO NSs over other supports and particularly that the features of Pd nanoparticles in facilitating the cleavage of the α-C-H bond of alcohols and adsorbing subsequently-generated C-centered radicals hold the key to turning on the reaction. This work highlights a new insight into radical-induced efficient benzimidazole synthesis pairing with H2 evolution by rationally designing semiconductor-based photoredox systems.
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INTRODUCTION: Allergic fungal rhinosinusitis (AFRS) is characterized by refractory and high recurrence rate. Improper treatment may lead to repeated recurrence and even serious complications, including vision loss, blindness, and intracranial complications. However, AFRS is easy to be misdiagnosed clinically. OBJECTIVE: To ensure early diagnosis, the clinical presentations of patients with AFRS were studied. METHODS: Data from patients with sinusitis hospitalized in the First Affiliated Hospital of the University of Science and Technology of China (USTC) from January 2015 to October 2022 were collected. The patients were divided into three groups; group A patients with AFRS, group B patients suspected of AFRS, and group C patients with fungus ball sinusitis (FBS).We retrospectively analyzed the data using IBM SPSS 19.0 to perform the chi-square test and one-way ANOVA test. RESULTS: In total, 35 cases of AFRS, 91 cases of suspected AFRS, and 661 cases of FBS were rediagnosed. Compared with FBS patients, AFRS patients were younger, the total IgE, the percentage of eosinophils and basophils in peripheral blood were higher, and the proportion of patients with allergic rhinitis, asthma or hypo olfactory was higher. It had a higher recurrence rate. These results were also observed in the comparison between suspected AFRS patients and FBS patients, but no significant difference was found in the comparison between suspected AFRS patients and suspected AFRS patients. CONCLUSIONS AND SIGNIFICANCE: AFRS may be misdiagnosed due to the low detection of fungi. To ensure early diagnosis, we recommend that patients with clinical, radiological, and laboratory features similar to those of AFRS but without evidence of fungal staining be treated according to the treatment criteria of AFRS.
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A novel actinobacterium, designated strain CRSS-Y-16T, was isolated from the healthy leaves of Xanthium sibiricum, in China and characterized by a polyphasic approach. This strain produced abundant aerial mycelia that generated rod-shaped spores with spiny surfaces. The cell wall contained LL-diaminopimelic acid. The major cellular fatty acids (>10.0%) were C16:0, iso-C16:0, and C18:1 ω9c. The predominant menaquinones were MK-9(H2) and MK-9(H4). The detected polar lipids were diphosphatidylglycerol, hydroxyl phosphatidylethanolamine, phosphatidylethanolamine, phosphatidylinositolmannoside, phospholipids of unknown structure containing glucosamine and unidentified phospholipids. The genomic G+C content was 70.7%. The full-length 16S rRNA gene sequence analysis indicated that strain CRSS-Y-16T belonged to the genus Streptomyces and shared <98.7% sequence similarities with all recognized type species of the genus. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain formed a distinct branch. Phylogenomic analysis demonstrated that it was closely related to Streptomyces panaciradicis 1MR-8T. However, the clustering patterns resulting from phylogenomic tree verified that strain CRSS-Y-16T represented a novel Streptomyces species. This result was further confirmed by low average nucleotide identity and digital DNA-DNA hybridization values (87.54% and 30.1%) between them. Based on all these data, it is concluded that strain CRSS-Y-16T represents a novel Streptomyces species, for which the name Streptomyces spinosirectus sp. nov. is proposed. The type strain is CRSS-Y-16T (=MCCC 1K06950T=JCM 35007T).
Asunto(s)
Plantas Medicinales , Streptomyces , Xanthium , Filogenia , ARN Ribosómico 16S/genética , Streptomyces/genética , ADNRESUMEN
OBJECTIVE: To evaluate the obstetrical and oncological progression of twin pregnancies with hydatidiform mole coexisting fetus (HMCF). MATERIALS AND METHODS: Using a retrospective method based on patients from the Women's Hospital, Zhejiang University School of Medicine database between January 1990 and October 2020, 17 patients were histologically confirmed as having HMCF, and the patients' prenatal diagnosis, outcomes and development of gestational trophoblastic neoplasia (GTN) were reviewed. RESULTS: Among these 17 cases, 11 (64.71%) cases were complete hydatidiform mole coexisting fetus (CHMCF), and 6 (35.29%) cases were partial hydatidiform mole coexisting fetus (PHMCF). The gestational age at diagnosis of CHMCF was significantly earlier than that of PHMCF [9 (8-24) vs. 18 (11-32) weeks, respectively, P < 0.05]. The live birth rate of PHMCF was slightly higher than that of CHMCF (33.33%; 18.18%), but this difference was not statistically significant. The overall rate of GTN incidence of HMCF was 47.06% (8/17), and the GTN rates of PHMCF and CHMCF were 33.33% (2/6) and 54.55% (6/11), respectively. There was no significant difference in the GTN rate between patients who chose to continue pregnancy and those who terminated pregnancy before 24 weeks of gestation. The GTN rate of patients with term delivery was not significantly higher than that of preterm delivery. CONCLUSION: In HMCF cases, the incidence rate of CHMCF was higher than that of PHMCF, and PHMCF is more difficult to diagnose in the early stage. Continuing pregnancy does not increase the risk of GTN compared to terminating pregnancy. In cases of HMCF, when the fetal karyotype is normal and maternal complications are controlled, it is safe to continue the pregnancy and extend it to term.
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Enfermedad Trofoblástica Gestacional , Mola Hidatiforme , Neoplasias Uterinas , Femenino , Feto , Humanos , Mola Hidatiforme/diagnóstico , Mola Hidatiforme/epidemiología , Recién Nacido , Embarazo , Embarazo Gemelar , Estudios Retrospectivos , Neoplasias Uterinas/diagnósticoRESUMEN
To combine both electride and alkalide characteristics in one molecular switch, it is shown herein that the phenalenyl radical and the M3 ring (M3-PHY, M = Li, Na, and K) stacked with parallel and vertical geometries are good candidates. The former geometry is the superalkali electride e-â¯M3+-PHY while the latter geometry is the superalkalide Mδ--M2(1-δ)+-PHY-. The superalkalide Mδ--M2(1-δ)+-PHY- may isomerize to the superalkali electride e-â¯M3+-PHY (M = Li, Na, and K) using suitable long-wavelength irradiation, while the latter may isomerize to the former with suitable short-wavelength irradiation. Also, applying suitable oriented external electric fields can drive the superalkalide Mδ-M2(1-δ)+-PHY- to change into the superalkali electride e-â¯M3+-PHY (M = Li, Na, and K). The differences in the static and dynamic first hyperpolarizability (ß0) values between them were also studied.
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Two novel chiral conjugated polymers R-P and S-P designed and synthesized from a pair of circularly polarized thermally activated delayed fluorescence (CP-TADF) enantiomers are presented in this work. The two polymers exhibited excellent TADF properties with small singlet-triplet energy gaps (ΔEST) of 0.045 and 0.061 eV and relatively high photoluminescence quantum yields (PLQYs) of 72 and 76%, respectively. Besides, intense mirror-image circularly polarized luminescence signals were detected from R-P and S-P in both solution and film states with dissymmetry factors (|glum|) of up to 1.9 × 10-3. Furthermore, solution-processed circularly polarized polymer light-emitting diodes (CP-PLEDs) fabricated with R-P and S-P achieved high maximum external quantum efficiencies of 14.9 and 15.8% and high maximum brightness (Lmax) of 8940 and 12,180 cd/m2 with yellowish-green emission peaks at 546 and 544 nm, respectively. Moreover, intense circularly polarized electroluminescence signals with electroluminescence dissymmetry factors (gEL) of -1.5 × 10-3 and +1.6 × 10-3 were detected from the CP-PLED devices fabricated with R-P and S-P, respectively.
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Triptycene derivatives, a type of specific aromatic compound, have been attracting much attention in many research areas. Over the past several years, triptycene and its derivatives have been described to be useful and efficient building blocks for the design and synthesis of novel supramolecular acceptors, porous materials and luminescent materials with specific structures and properties. In this review, recent researches on triptycene derivatives in supramolecular and materials chemistry are summarized. Especially, the construction of a new type of macrocyclic arenes and organic cages with triptycene and its derivatives as building blocks are focused on, and their applications in molecular recognition, self-assembly and gas selective sorption are highlighted. Moreover, the applications of triptycene and its derivatives in porous organic materials and thermally activated delayed fluorescence (TADF) materials are also discussed.
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Planar chiral organic fluorescent materials that exhibit high chiral stability, high efficiency and circularly polarized luminescence (CPL) currently remain an unresolved issue despite their promising applications in optical encryption and 3D-display. Herein, a pair of new donor-chiral π-acceptor (D-π*-A) type planar chiral thermally activated delayed fluorescence (TADF) enantiomers, namely R/S-PXZ-PT, are developed. Such a D-π*-A type structure completely suppresses the racemisation of the planar chirality, making it possible to prepare circularly polarized organic light-emitting diodes (CP-OLEDs) by vacuum deposition processing. Moreover, this design perfectly integrates the chiral unit into the luminescent unit to achieve intense CPL activity with luminescence asymmetry factors (glum) of ±1.9 × 10-3. Notably, the enantiomer-based devices exhibit a yellow coloured emission with a maximum external quantum efficiency (EQE) of 20.1%, and mirror-image circularly polarized electroluminescence signals with electroluminescence dissymmetry factors (gEL) of +1.5 × 10-3/-1.3 × 10-3. This work not only enriches the diversity of chiral TADF molecular design, but also provides a new perspective for the development of highly-efficient CP-OLEDs with stable planar chiral TADF materials.
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A strategy of chiral donor-acceptor copolymerization is proposed to develop chiral nonconjugated polymers with thermally activated delayed fluorescence (TADF). Based on this strategy, two pairs of chiral polymers (R,R)-/(S,S)-pTpAcDPS and (R,R)-/(S,S)-pTpAcBP were synthesized. The alternating copolymerization of the chiral donors and acceptors could effectively separate the frontier molecular orbitals, which made the polymers show small ΔEST of 0.01-0.03â eV and efficient TADF properties. Moreover, the polymers also showed the quantum yield of up to 92 % and the circularly polarized luminescence. The solution-processed circularly polarized organic light-emitting diodes showed circularly polarized electroluminescence signals with high external quantum efficiencies of up to 22.1 % and maximum luminance of up to 34350â cd m-2 . This is the first report of CP-OLEDs based on chiral TADF polymer, which provides a useful and valuable guidance for the development of high-efficiency CPEL polymers.
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A couple of fluorescent enantiomers, which are suitable for the emitters of high-efficiency TADF-sensitized CP-OLEDs, have been developed. The enantiomers show configurational stability, high PLQY of 98 %, large kr of 7.8×107 â s-1 , and intense CPL activities with |glum | values of about 2.5×10-3 . Notably, by using matchable TADF sensitizer, the enantiomers were then exploited as emitter to fabricate CP-OLEDs. The TADF-sensitized CP-OLEDs not only show mirror-image CPEL activities with gEL values of +1.8×10-3 and -1.4×10-3 , but also display fast start-up featuring with low VT of 3.0â V as well as driving voltage of 4.8â V at 10 000â cd m-2 . Meaningfully, the TADF-sensitized fluorescent devices show high EQEmax of 21.5 % and extremely low efficiency roll-off, whose EQEs are 21.2 % and 15.3 % at 1000 and 10 000â cd m-2 , respectively. The obtained EQEs are comparable to those of CP-TADF emitters, which provides a promising perspective to break through the EL efficiency limit of CP-FL emitters.
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The design and synthesis of nitrogen-doped aromatic belts with conjugated structures still remain a challenge. Here, we report the first nitrogen-doped aromatic belt with a [6]cycloparaphenylene skeleton, which is conveniently synthesized from the easily available calix[3]carbazole. The aromatic belt has a rigid conjugated structure and deep cavity, and it can encapsulate one dichloromethane both in solution and in the solid state. Interestingly, the aromatic belt shows strong green fluorescence with a quantum yield of 0.39 and exhibits a narrow HOMO-LUMO energy gap of 2.02â eV. The belt-shaped conjugated structure composed of three carbazole subunits has specific optoelectronic properties that will promote wide applications in supramolecular chemistry and materials science.
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The exploration of innovative molecular switches has resulted in large developments in the field of molecular electronics. Focusing on a single molecular switch with different forms exhibiting different electride features, potassium-atom-doped all-cis 1,2,3,4,5,6-hexafluorocyclohexane K-F6C6H6 was studied theoretically. It was found that an oriented external electric field can drive excess electron transfer from the region outside of the K atom to that outside of F6C6H6. Subsequently, the electride-like molecule K-F6C6H6 (1) switches into the molecular electride K-F6C6H6e- (3) through another electride-like molecule K-F6C6H6 (2). The static first hyperpolarizabilities (ß0) are increased over 12- and 5-fold when moving from 1 to 2 and 3, respectively. The rise of each ß0 value constitutes an order of magnitude improvement. Between them, the different ß0 values suggest that K-F6C6H6 is a good candidate for use as a multiple-response nonlinear optics switch. The order of the ß0 values of 1-4 for M-F6C6H6 (M = Li and Na) coincide with that of K-F6C6H6, also exhibiting a switch effect.
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A novel intra-molecular self-redox switch, Li3N3Mg, is constructed theoretically. Our investigation showed that a suitably oriented external electric field (OEEF) can drive a long-range excess electron transfer from Mg atoms to Li3 rings. And subsequently, an interesting intra-molecular self-redox from Li32+N33-Mg+ to Li3+N33-Mg2+ accompanying the large different electronic static first hyperpolarizability (ß) is exhibited. The increase of the ß value constitutes an order of magnitude improvement from Li32+N33-Mg+ (34 986 a.u.) to Li3+N33-Mg2+ (101 225 a.u.), which indicates that Li3N3Mg is a good candidate for a self-redox NLO molecular switch.