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Noncentrosymmetry (NCS) is a prerequisite for second-order nonlinear optical (NLO) materials. In this work, a new polycation-substitution-induced centrosymmetry (CS)-to-NCS transformation strategy was applied in CS RbGaS2, affording two novel NCS salt-inclusion chalcogenides: [ABa2Cl][Ga4S8] (A = Rb, 1; Cs, 2). Remarkably, they exhibit the key merits of both Vis and IR NLO candidates, including strong phase-matchable second harmonic generation intensities (10.4-15.3 × KH2PO4 at 1064 nm; 0.9-1.0 × AgGaS2 at 1910 nm), high laser-induced damage thresholds (11-12 × AgGaS2), and a wide transparent window. Their prominent NLO performances originate from the orderly packing of T2-supertetrahedral Ga4S10 motifs resulting from the template effect of acentric polycation [ClA2Ba3]7+. The CS-to-NCS transformation first realized by polycation-substitution-induced NLO-functional motif ordering provides an effective approach for designing new NLO materials.
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A large nonlinear optical (NLO) coefficient and a wide band gap are two crucial but contradictory parameters that are difficult to achieve simultaneously in a single infrared (IR) NLO compound. A salt-inclusion chalcogenide (SIC), Li[LiCs2 Cl][Ga3 S6 ] (1), was prepared that presents a nanosized tunnel framework constructed from monotype chalcogenide tetrahedra. Highly oriented covalent GaS4 tetrahedra in the host lead to a moderate second harmonic generation response (0.7 AgGaS2 ), and ionic guests effectively broaden the band gap to the widest value (4.18â eV) among all IR NLO chalcogenides, thereby achieving a remarkable balance between NLO efficiency and band gap.
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Two new infrared (IR) nonlinear optical (NLO) sulfides, Na2Ga2GeS6 and Na2Ga2SnS6, were obtained by mixing different typical NLO-active motifs GaS4 and GeS4/SnS4 in the alkali metal-containing system. The IR NLO sulfides present laser-induced damage thresholds that are 18.1 and 17.9 times that of the reference AgGaS2 (AGS) and second-harmonic generation efficiencies that are 0.8 and 1.1 times that of AGS. These properties originate from the GaS4, GeS4, and SnS4 tetrahedral blocks in the structures of the sulfides. Both compounds also exhibit a broad transparency range and type-I phase-matching behavior, which support their high potential in high-power laser applications. This work sheds new light on the development of promising mid-IR NLO materials by combining different NLO-active motifs.
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Two new phases in the Ag-Cd-P-S system containing two second-order Jahn-Teller (SOJT) distorted d10 cations (Cd2+ and Ag+), namely, Ag2Cd(P2S6) (1) and AgCd3(PS4)S2 (2), are obtained via medium-temperature solid-state synthesis. Compound 1 exhibits a two-dimensional layered structure and undergoes a first-order structural phase transition at approximately 280 °C. This outcome can be ascribed to the significant mismatch in the expansion coefficients between Cd-S (Ag-S) and P-P (P-S) bonds evaluated through bond valence theory. The three-dimensional non-centrosymmetric (NCS) framework of 2 is constructed by two types of tetrahedral layers consisting of corner-shared CdS4, AgS4, and PS4 tetrahedra. Compound 2 exhibits second harmonic generation (SHG) intensity of 0.45 times that of commercial AgGaS2 (AGS) at a laser irradiation of 1.85 µm and an optical band gap of 2.56 eV, and no intrinsic vibrational absorption of chemical bonds is observed in the range of 2.5-18.2 µm. Both phase transition in 1 and SHG properties in 2 are closely related to the SOJT distorted d10 cations and diverse phosphorus-sulfur polyanions (PaSb)n-, which together can easily result in NCS distorted structures and interesting properties.
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Quaternary metal thiophosphates containing second-order Jahn-Teller distorted d10 Ag+ and lone-pair cations, Ag3Bi(PS4)2 (1), Ag7Sn(PS4)3 (2), and Ag7Pb(PS4)3 (3), were obtained by solid-state synthesis. The structural frameworks of 2 and 3 feature an infinite 1-D interchiral double helix ∞1(Ag3P2S11), which is rare in inorganic compounds. Compound 3 undergoes a significant first-order structural phase transition from monoclinic to hexagonal at â¼204 °C. This can be ascribed to the significant mismatch in the expansion coefficients between Pb-S (Ag-S) and P-S bonds evaluated by bond valence theory. The three compounds are Ag+ ionic conductors, and Ag+ ion migration pathways are proposed by calculating maps of low bond valence mismatch. Moreover, the optical properties of the three compounds were studied, and electronic structure calculations were performed. The combination of second-order Jahn-Teller distorted d10 cation and lone-pair cation provides a new strategy to explore new metal thiophosphates with interesting structures and promising properties.
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The first two new Na-containing sulfides Na2In2MS6 (M = Si (1), Ge (2)) in the Na2Q-B2Q3-CQ2 (B = Ga, In; C = Si, Ge, Sn; Q = S, Se) system were prepared for the first time through conventional high-temperature solid-state reaction. They are isostructural with space group Cc (No. 9) in monoclinic phases and feature three-dimensional frameworks built by the (∞)¹[In2MS6]²â» (M = Si, Ge) chains through corner-sharing InS4 tetrahedra and MS4 (M = Si, Ge) tetrahedra, with Na⺠cation located in the cavities. They display moderate second harmonic generation (SHG) conversion efficiencies compared with commercial AgGaS2, with phase-matching behavior at 1800 nm and laser-induced damage thresholds 6.9 and 4.0 times higher than that of AgGaS2, respectively. Therefore, the output SHG intensities of 1 and 2 will be â¼4.3 and 4.0 times larger than that of AgGaS2, when the intensity of incident laser increased to close the damage energy of 1 and 2, indicating their potential for high-power nonlinear optical application.
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Two new metal sulfides, Ba(2)Ga(8)MS(16) (M = Si, Ge), have been synthesized by high-temperature solid-state reactions. They are isostructural and crystallize in the noncentrosymmetric space group P6(3)mc (No. 186) with a = 10.866(5) Å, c = 11.919(8) Å, and z = 2 for Ba(2)Ga(8)SiS(16) (1) and a = 10.886(8) Å, c = 11.915(3) Å, and z = 2 for Ba(2)Ga(8)GeS(16) (2). Their three-dimensional frameworks are constructed by corner-sharing mixed (Ga/M)S(4) (M = Si, Ge) and pure GaS(4) tetrahedra, with Ba(2+) cations filling in the tunnels. Compounds 1 and 2 are transparent over 0.42-20 µm and have wide band gaps of around 3.4 and 3.0 eV, respectively. Polycrystalline 2 displays strong nonlinear second-harmonic-generation (SHG) intensities that are comparable to that of the benchmark AgGaS(2) (AGS) with phase-matching behavior at a laser irradiation of 1950 nm. Of particular interest, compound 2 also possesses a high powder laser-induced damage threshold of â¼22 times that of AGS. The alternate stacking of the mixed (Ga/M)S(4) (M = Si, Ge) tetrahedral layer with the pure GaS(4) tetrahedral layer along the c axis and the alignment of these two types of tetrahedra in the same direction may be responsible for the large SHG signals observed.
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Purpose: Degeneration of retinal photoreceptors is frequently observed in diverse ciliopathy disorders, and photoreceptor cilium gates the molecular trafficking between the inner and the outer segment (OS). This study aims to generate a homozygous global Cep250 knockout (KO) mouse and study the resulting phenotype. Methods: We used Cep250 KO mice and untargeted metabolomics to uncover potential mechanisms underlying retinal degeneration. Long-term follow-up studies using optical coherence tomography (OCT) and electroretinography (ERG) were performed. Results: OCT and ERG results demonstrated gradual thinning of the outer nuclear layer (ONL) and progressive attenuation of the scotopic ERG responses in Cep250-/- mice. More TUNEL signal was observed in the ONL of these mice. Immunostaining of selected OS proteins revealed mislocalization of these proteins in the ONL of Cep250-/- mice. Interestingly, untargeted metabolomics analysis revealed arginine-related metabolic pathways were altered and enriched in Cep250-/- mice. Mis-localization of a key protein in the arginine metabolism pathway, arginase 1 (ARG1), in the ONL of KO mice further supports this model. Moreover, adeno-associated virus (AAV)-based retinal knockdown of Arg1 led to similar architectural and functional alterations in wild-type retinas. Conclusions: Altogether, these results suggest that dysregulated arginine metabolism contributes to retinal degeneration in Cep250-/- mice. Our findings provide novel insights that increase understanding of retinal degeneration in ciliopathy disorders.
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Ciliopatias , Degeneração Retiniana , Animais , Camundongos , Arginina , Camundongos Knockout , RetinaRESUMO
Background: Neurodegenerative retinal diseases such as retinitis pigmentosa are serious disorders that may cause irreversible visual impairment. Ferroptosis is a novel type of programmed cell death, and the involvement of ferroptosis in retinal degeneration is still unclear. This study aimed to investigate the related ferroptosis genes in a mice model of retinal degeneration induced by light damage. Methods: A public dataset of GSE10528 deriving from the Gene Expression Omnibus database was analyzed to identify the differentially expressed genes (DEGs). Gene set enrichment analysis between light damage and control group was conducted. The differentially expressed ferroptosis-related genes (DE-FRGs) were subsequently identified by intersecting the DEGs with a ferroptosis genes dataset retrieved from the FerrDb database. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were further performed using the DE-FRGs. A protein-protein interaction (PPI) network was constructed to identify hub ferroptosis-related genes (HFRGs). The microRNAs (miRNAs)-HFRGs, transcription factors (TFs)-HFRGs networks as well as target drugs potentially interacting with HFRGs were analyzed utilizing bioinformatics algorithms. Results: A total of 932 DEGs were identified between the light damage and control group. Among these, 25 genes were associated with ferroptosis. GO and KEGG analyses revealed that these DE-FRGs were mainly enriched in apoptotic signaling pathway, response to oxidative stress and autophagy, ferroptosis, necroptosis and cytosolic DNA-sensing pathway. Through PPI network analysis, six hub ferroptosis-related genes (Jun, Stat3, Hmox1, Atf3, Hspa5 and Ripk1) were ultimately identified. All of them were upregulated in light damage retinas, as verified by the GSE146176 dataset. Bioinformatics analyses predicated that 116 miRNAs, 23 TFs and several potential therapeutic compounds might interact with the identified HFRGs. Conclusion: Our study may provide novel potential biomarkers, therapeutic targets and new insights into the ferroptosis landscape in retinal neurodegenerative diseases.
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Purpose: Abundant retinal microRNA-183 cluster (miR-183C) has been reported to be a key player in photoreceptor development and functionality in mice. However, whether there is a protagonist in this cluster remains unclear. Here, we used a mutant mouse model to study the role of miR-96, a member of miR-183C, in photoreceptor development and functionality. Methods: The mature miR-96 sequence was removed using the CRISPR/Cas9 genome-editing system. Electroretinogram (ERG) and optical coherence tomography (OCT) investigated the changes in structure and function in mouse retinas. Immunostaining determined the localization and morphology of the retinal cells. RNA sequencing was conducted to observe retinal transcription alterations. Results: The miR-96 mutant mice exhibited cone developmental delay, as occurs in miR-183/96 double knockout mice. Immunostaining of cone-specific marker genes revealed cone nucleus mislocalization and exiguous Opn1mw/Opn1sw in the mutant (MT) mouse outer segments at postnatal day 10. Interestingly, this phenomenon could be relieved in the adult stages. Transcriptome analysis revealed activation of microtubule-, actin filament-, and cilia-related pathways, further supporting the findings. Based on ERG and OCT results at different ages, the MT mice displayed developmental delay not only in cones but also in rods. In addition, a group of miR-96 potential direct and indirect target genes was summarized for interpretation and further studies of miR-96-related retinal developmental defects. Conclusions: Depletion of miR-96 delayed but did not arrest photoreceptor development in mice. This miRNA is indispensable for mouse photoreceptor maturation, especially for cones.
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MicroRNAs , Células Fotorreceptoras Retinianas Cones , Animais , Eletrorretinografia , Camundongos , Camundongos Knockout , MicroRNAs/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismoRESUMO
Two inorganic supramolecular compounds, (Hg(6)P(3))(In(2)Cl(9)) (1) and (Hg(8)As(4))(Bi(3)Cl(13)) (2), which have chiral 3-D host frameworks with guest moieties filling the helical tunnels, have been synthesized. They both have large second-harmonic generation efficiencies, and compound 2 also exhibits obvious single-crystal piezoelectric performance. Theoretical studies from first-principles calculations were performed on their nonlinear optical (NLO) and piezoelectric properties, and results indicate that good NLO and piezoelectric materials can be obtained by designing both complicated polycations and polyanions with large molecular polarizability as functional components rather than traditional single polyanions.
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1,10-Phenanthroline (phen) and monoprotonated methylamine molecules were used as a novel cotemplate to direct the formation of a new inorganic-organic hybrid selenidostannate, (CH(3)NH(3))(4)(Sn(2)Se(6))·6phen (1); while the utilization of three types of transition-metal (TM) phen complex cations with the TM/phen ration of 1:1, 1:2, and 1:3 as structure directors affords {[Mn(phen)(2)](2)(µ(2)-Sn(2)Se(6))}·H(2)O (2a), {[Fe(phen)(2)](2)(µ(2)-Sn(2)Se(6))} (2b), {[Mn(phen)](2)(µ(4)-Sn(2)Se(6))}(n) (3), {[Mn(phen)(2)](Sn(2)Se(5))}(n) (4), and [Fe(phen)(3)](n)(Sn(3)Se(7))(n)·1.25nH(2)O (5). These compounds show diverse structures with the selenidostannate anions varying from discrete, µ(2)- and µ(4)- (Sn(2)Se(6))(4-) anions, to one-dimensional (1-D) (1)(∞)(Sn(2)Se(5)(2-)) anionic chains, and two-dimensional (2-D) extended (2)(∞)(Sn(3)Se(7)(2-)) anionic layers, demonstrating different structure-directing abilities of the cotemplate and the three types of TM phen complex cations. This work clearly indicates that the approach of modifying the number of the free coordination sites of unsaturated TM phen complex cations is very exciting as a way to synthesize novel hybrid chalcogenidometalates. Of particular interest, the present compounds exhibit interesting optical properties that reflect the combined effects of both photoluminescence-active organic components and semiconducting inorganic chalcogenidometalate anionic networks.
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Exploration of a new nonlinear optical (NLO)-active functional motif is important in the rational design of promising infrared (IR) NLO materials. Compared with typical tetrahedral MQ4 (M = IIB, III, IV metals; Q = S, Se) motifs, MQ3 (M = As, Sb) pyramids favor high second-harmonic generation (SHG) efficiency while frequently hindering phase matching (PM) because of excessively large optical anisotropy. The surfactant-thermal method was first adopted to achieve PM in MQ3-containing systems and synthesize mixed covalent-ionic IR NLO materials. Two new thioarsenates of AMnAs3S6 (A = Cs, Rb) exhibiting strong PM SHG efficiencies comparable to commercial AGS and laser-induced damage thresholds of one order higher than AGS were obtained. The [As3S6]3- unit in their structures is an unprecedented NLO-active functional motif, which can be useful in designing new IR NLO compounds with large SHG efficiency. In addition, the surfactant-thermal method provides a new general strategy for synthesizing new IR NLO materials.
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A novel zinc(II) 4-(5H-tetrazol)benzoic coordination polymer with an in situ generated tetrazole ligand exhibits the gsi (gamma-silicon) topology and high thermal stability; this compound possesses second-order nonlinear optical and interesting heat-induced photoluminescent properties.
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The seven new isostructural quaternary uranium chalcogenides KCuUS 3, RbCuUS 3, RbAgUS 3, CsCuUS 3, CsAgUS 3, RbAgUSe 3, and CsAgUSe 3 were prepared from solid-state reactions. These isostructural materials crystallize in the layered KZrCuS 3 structure type in the orthorhombic space group Cmcm. The structure is composed of UQ 6 octahedra and MQ 4 tetrahedra that share edges to form (2) infinity[UMQ 3 (-)] layers. These layers stack perpendicular to [010] and are separated by layers of face- and edge-sharing AQ 8 bicapped trigonal prisms. There are no Q-Q bonds in the structure, so the formal oxidation states of A/U/M/Q may be assigned as 1+/4+/1+/2-, respectively. CsCuUS 3 shows semiconducting behavior with thermal activation energy E a = 0.14 eV and sigma 298 = 0.3 S/cm. From single-crystal absorption measurements in the near IR range, the optical band gaps of these compounds are smaller than 0.73 eV. The more diffuse 5f electrons play a much more dominant role in the optical properties of the AMUQ 3 compounds than do the 4f electrons in the AMLnQ 3 compounds (Ln = rare earth). Periodic DFT spin band-structure calculations on CsCuUS 3 and CsAgUS 3 establish two energetically similar antiferromagnetic spin structures and show magnetic interactions within and between the layers of the structure. Density-of-states analysis shows M-Q orbital overlap in the valence band and U-Q orbital overlap in the conduction band.
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To circumvent the incompatibility between large nonlinear optical (NLO) efficiencies and high laser-induced damage thresholds (LIDTs) in mid-infrared NLO materials, a new strategy for designing materials with both excellent properties is proposed. This strategy involves narrowing the band gap for large NLO efficiencies and reducing the thermal effect for a high LIDT. To support these proposals, a series of isostructural chalcogenides with various tetrahedral center cations, Na2Ga2MQ6 (M = Ge, Sn; Q = S, Se), were synthesized and studied in detail. Compared with the benchmark AGS, these chalcogenides exhibit significantly narrower band gaps (1.56-1.73 eV, AGS: 2.62 eV) and high NLO efficiencies (1.6-3.9 times that of AGS at 1910 nm), and also outstanding LIDTs of 8.5-13.3 × those of AGS for potential high-power applications, which are contrary to the conventional band gap view but can be attributed to their small thermal expansion anisotropy, surmounting the NLO-LIDT incompatibility. These results shed light on the search for practical IR NLO materials with excellent performance not restricted by NLO-LIDT incompatibility.
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OBJECTIVE: To explore the diagnostic efficiency of DNA-based and RNA-based quantitative polymerase chain reaction (qPCR) analyses for periprosthetic joint infection (PJI). METHODS: To determine the detection limit of DNA-based and RNA-based qPCR in vitro, Staphylococcus aureus and Escherichia coli strains were added to sterile synovial fluid obtained from a patient with knee osteoarthritis. Serial dilutions of samples were analyzed by DNA-based and RNA-based qPCR. Clinically, patients who were suspected of having PJI and eventually underwent revision arthroplasty in our hospital from July 2014 to December 2016 were screened. Preoperative puncture or intraoperative collection was performed on patients who met the inclusion and exclusion criteria to obtain synovial fluid. DNA-based and RNA-based PCR analyses and culture were performed on each synovial fluid sample. The patients' demographic characteristics, medical history, and laboratory test results were recorded. The diagnostic efficiency of both PCR assays was compared with culture methods. RESULTS: The in vitro analysis demonstrated that DNA-based qPCR assay was highly sensitive, with the detection limit being 1200 colony forming units (CFU)/mL of S. aureus and 3200 CFU/mL of E. coli. Meanwhile, The RNA-based qPCR assay could detect 2300 CFU/mL of S. aureus and 11 000 CFU/mL of E. coli. Clinically, the sensitivity, specificity, and accuracy were 65.7%, 100%, and 81.6%, respectively, for the culture method; 81.5%, 84.8%, and 83.1%, respectively, for DNA-based qPCR; and 73.6%, 100%, and 85.9%, respectively, for RNA-based qPCR. CONCLUSIONS: DNA-based qPCR could detect suspected PJI with high sensitivity after antibiotic therapy. RNA-based qPCR could reduce the false positive rates of DNA-based assays. qPCR-based methods could improve the efficiency of PJI diagnosis.
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Antibacterianos/uso terapêutico , DNA Bacteriano/análise , Prótese do Joelho/efeitos adversos , Infecções Relacionadas à Prótese/diagnóstico , RNA Bacteriano/análise , Idoso , Artroplastia do Joelho , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Reação em Cadeia da Polimerase/métodos , Cuidados Pós-Operatórios/métodos , Infecções Relacionadas à Prótese/microbiologia , Sensibilidade e Especificidade , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/isolamento & purificação , Líquido Sinovial/microbiologiaRESUMO
Mid-far infrared (IR) non-linear optical (NLO) materials are of great importance in military and civil fields. However, commercial IR-NLO crystals (such as AgGaS2, AgGaSe2 and ZnGeP2) do not currently satisfy the requirements of large second-harmonic generation (SHG) and high laser induced damage thresholds (LIDTs), which seriously limits their practical applications. Herein, we have developed a new series of salt-inclusion chalcogenides, [A3X][Ga3PS8] (A = K, Rb; X = Cl, Br), which are constructed from alternate stacking of adamantane-like [Ga3PS10]6- cluster layers and cationic [A3X]2+ salt layers. Importantly, they display both large SHG responses of several-fold and high LIDTs for dozens of times that of commercial AgGaS2, which exhibit the highest LIDTs among the reported IR-NLO materials with a larger SHG conversion efficiency than that of AgGaS2. These properties together with wide transparent region, type I phase-matching features and congruent-melting behaviors indicate they are promising IR-NLO materials.
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The cluster compounds with d9-d9 magnetic system were investigated because of their magnetic character. Some of the copper(II) compounds with terephthalato as bridged unit, [{Cu(bipy) [C6H4(COO)2]}2.H2O]n and [Cu(phen) [C6H4(COO)2]]n, have been synthesized through a solvothermal reaction, and their crystal structures have been determined by X-ray diffraction. Their shape looks like zigzag-chain. In this paper, the molecular vibration spectra of the title complexes have been studied in detail. The middle and far-infrared spectra, and Raman spectra of the compounds have been reported and their assignments have been made experientially. The characteristic carbonyl absorption of terephthalato group at 1688 cm(-1) disappeared while the complexes formed. The characteristic peaks of COO- group were splited into two peaks respectively that appeared at 1603, 1574 cm(-1) (vasCOO) and 1369, 1356 cm(-1) (vsCOO) in [{Cu(bipy)[C6H4(COO)2]}2.H2O]n, and at 1614, 1605 cm(-1) (vasCOO) and 1373, 1344 cm(-1) (vsCOO) in [Cu(phen) [C6H4(COO)2]]n. The relationship between the structures of the compounds and the spectra has been discussed as well. The coincidence between experiential assignments and the theoretic calculation will be confirmed.
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Two new inorganic supramolecular compounds, (Hg11P4)(GaCl4)4 (1) and (Hg3AsS)(GaCl4) (2), have been prepared by the solid-state reactions. Their structures are characterized by mercury-containing cationic hosts and discrete (GaCl4)(-) guests, which is a derivative of a very strong Lewis acid. The three-dimensional cationic framework of 1, (Hg11P4)(4+), is marvellously extended by Hg2(2+) and Hg3(2+) groups as well as Hg(2+) ions to form two large tunnels with different sizes each embedded with two columns of (GaCl4)(-) anions. Compound 2 features a layered structure with (GaCl4)(-) tetrahedra being intercalated between two-dimensional (Hg3AsS)(+) layers and it is the first mercury pnictidechalcohalide. It is found that the weak electrostatic forces between hosts and guests play a key role in the stabilization of the whole structures of 1 and 2, which is strikingly different from almost all the reported metal pnictidehalide and chalcohalide supramolecular compounds. Optical dielectric constants calculations show that both 1 and 2 possess strong dielectric anisotropy.