One-dimensional Chain Structure Research Articles

Hydrothermal preparation, crystal structure, Hirshfeld surface analysis, photophysical properties and antifungal activity of a series of complexes assembled by 5-bromo-2-(carboxymethoxy)benzoic acid ligands

Five complexes [Co(BCBA)(H2O)3]n (1), [Co(BCBA)(4,4′-Bipy)2·(H2O)]n (2), [Cu(BCBA)(H2O)]n (3), [Zn(BCBA)(H2O)]n (4) and [Cd(BCBA)(2,2′-Bipy)(H2O)·(H2O)]n (5) (H2BCBA= 5‑bromo-2-(carboxymethoxy)benzoic acid, 4,4′-Bipy = 4,4′-bipyridine and 2,2′-Bipy = 2,2′-bipyridine) have been synthesized with H2BCBA ligand by solvothermal condition. All the complexes have been structurally characterized by infrared spectra (IR), elemental analyses and single-crystal X-ray diffraction analyses. Complex 1 is a zero-dimensional structure, and complexes 2–5 are one-dimensional chain structure. Furthermore, thermogravimetric analyses (TGA), Hirshfeld surface analysis, photo-luminescence properties, Solid-state UV–Vis diffuse reflectance spectroscopy and antifungal activity for complexes 1–5 were investigated. The reciprocal H···O/H/Br/C contacts dominate over 86 % of total Hirshfeld surface. Complexes 1–5 have certain inhibitory effects on 8 pathogenic fungi. Among them, complex 5 has the strongest antibacterial activity against Rhizoctonia solani AG1, Sphaeropsis sapinea and Colletotrichum fructicola, and the inhibitory rate reached 100 %.

Amylopectin induces chain porous carbon skeleton boosting high performance of Na3V2(PO4)3

Poor conductivity and stability seriously hinder the development of Na3V2(PO4)3 (NVP). In current work, we use a facile hydrothermal method to dissolve low-cost amylopectin in urea as an additional carbon source for in-situ modification of NVP. The unique amylopectin, as structure guide agent, induces the formation of one-dimensional chain structure to cross each other. The gas produced in the urea decomposition process promotes the generation of pores on the one-dimensional chain structure. Finally, one-dimensional chain porous carbon skeleton is constructed. Plentiful defects and active sites are formed in the N-doped carbon derived from urea, effectively promoting the ionic conductivity at interface of NVP grains. Notably, amylopectin can induce the O atom in NVP bulk to escape from the crystal and combine with the N atom in carbon layer to form an N–O bond, thus generating abundant oxygen vacancy inside the NVP bulk. This special effect can reduce the resistance of Na+ transport in the crystal and enhance the connect bonds between the active particles and coated carbon substrate. Thus, both the ionic conductivity and the structural stability can be significantly improved. Moreover, the ex-situ SEM/TEM/XRD/XPS/CV/EIS measurements after cycling all demonstrate the optimized crystal structure and unique morphology can be perfectly maintained during the prolonged cycling process. The optimized NVP/C,N-0.25 sample reveals 116.3 mA h g−1 at 0.1 C. Even at 80 C, it still releases 74.4 mA h g−1 and maintains 51.2 mA h g−1 after 12,000 cycles, corresponding to a low decay rate of 0.0026 % per cycle.

Intermolecular Forces Regulating the Phase-Transition Temperatures in Organic-Inorganic Hybrid Materials.

Organic-inorganic hybrid phase-transition materials have attracted widespread attention in energy storage and sensor applications due to their structural adaptability and facile synthesis. However, increasing the phase-transition temperature (Tc) effectively remains a formidable challenge. In this study, we employed a strategy to regulate intermolecular interactions (different types of hydrogen bonds and other weak interactions), utilizing bismuth chloride as an inorganic framework and azetidine, 3,3-difluoro azetidine, and 3-carboxyl azetidine as organic components to synthesize three compounds with different Tc values: [C3H8N]2BiCl5 (1, 234 K), [C3H6NF2]3BiCl6 (2, 256 K), and [C4H8O2N]3BiCl6 (3, 350 K). 1 is a one-dimensional chain structure and 2 and 3 are zero-dimensional structures. Analysis of the crystal structure and the Hirshfeld surface and 2D fingerprints further suggests that the intermolecular forces are efficiently modulated. These findings emphasize the efficacy of our strategy in enhancing Tc and may facilitate further research in this area.

Synthesis, structure, fluorescence and magnetic studies of two oxygen bridged polycarboxylic acid ligands and rare earth metal ion Pr, Gd, and Er complexes

In order to further enrich the research on the synthesis of complexes with polycarboxylic acid ligands and rare earth metal ion. In this study, four rare earth complexes, namely, [Gd(cpia)]n (1), [Er(cpia)]n (2), [Pr(cpna)2·2H2O]n (3) and [Gd(Hcpna)(cpna)•3H2O]n (4) have been synthesized by solvothermal method based on 5-(2-carboxyphenoxy)isophthalic acid (H3cpia) and 5-(4-carboxyphenoxy)nicotinic acid ligand (H2cpna) with rare earth metal ions Pr3+, Gd3+ and Er3+. Single crystal X-ray diffraction analyses reveal that complexes 1, 2 and 3 are two-dimensional network structure, 4 is one-dimensional chain structures. The fluorescence test results show that the fluorescence intensity of complexes 1 and 2 were lower than that of the H3cpia ligand, the fluorescence intensity of complexes 3 and 4 were lower than that of the H2cpna ligand. Magnetic results indicate complex 1 has ferromagentic behavior and weak antiferromagentic behavior in the complexes 2, 3 and 4.

Preference in the Type of Halogen Bonding Interactions within Co-Crystals of Anthraquinone with a Pair of Isosteric Perhalobenzenes

The preference in the type of halogen bond accepted by anthraquinone (C14H8O2) from two isosteric donors, namely 1,4-diiodoperfluorobenzene (C6I2F4) and 1,4-diiodoperchlorobenzene (C6I2Cl4), is reported. The two co-crystals, (C6I2F4)·(C14H8O2) and (C6I2Cl4)·(C14H8O2), are sustained primarily by I···O rather than π-type halogen bonds to form these multicomponent solids. The ability for each component to engage in two divergent halogen-bonding interactions generates a one-dimensional chain structure for each co-crystal. The bias in the halogen-bonding type is due to the difference in electrostatic potential between the carbonyl oxygen and the aromatic surface on the anthraquinone. To support this observed preference, the binding energies of the I···O halogen bond were quantified for both co-crystals by using density functional theory calculations and then compared to the interaction energy for related π-type halogen bond from previously reported structures.

The effect of ligand/ metal-ligand ratio on the structural architectures of five different 1D zinc(II) coordination polymers with pyridyl derivative ligands

Five coordination compounds, [Zn(bppc)Cl]n·0.5nH2O (1) [Zn2(bppc)2(suc)]n (2), [Zn(dppb)Cl]n·nH2O (3) [Zn(dppb)Cl]n (4) [Zn2(dppb)2(bdc)]n·2nH2O(5) (Hbppc =2,6-bis(pyrazin-2-yl)pyridine-4-carboxylic acid, H2suc=succinic acid, Hdppb=4-(2,6-di(pyrazin-2-yl)pyridine-4-yl)-benzoic acid, H2bdc=1,4-benzenedicarboxylic acid), with the same one dimensions but different patterns have been hydrothermally synthesized and structurally characterized. Single crystal X-ray analysis revealed that compound 1 shows one-dimensional wave chain structure, compound 2 to 5 show one-dimensional ladder chain structure, one-dimensional V-shaped chain structure, one-dimensional linear chain structure and one-dimensional A-shaped chain structure, respectively. The structure differences of 1–5 show that ligand including auxiliary ligand and metal-ligand ratio have important influence on the final structures. Additionally, the luminescent properties of 1–5 have been investigated with fluorescent spectra in the solid state and fluorescence sensing experiments show that compound 1 exhibit a great selectivity and sensitivity for detection of Cu2+ion and nitrobenzene.

Two novel Zn(II)-thiazolothiazole extended viologen complexes with photochromism, inkless and erasable printing and photo-modulated luminescence

The insertion of conjugated units between the two pyridine rings of traditional viologens is an effective way to regulate the stimulus response. Herein, the rigid thiazolothiazole extended viologen moiety (TTVP, 2,5-bis (pyridinium-4-yl) thiazolo [5,4-d] thiazole propionate) has been utilized in the preparation of photochromic materials, in which two novel complexes {[Zn (TTVP)0.5 (m-HBTC) (H2O)]·DMF·3H2O}n (1) and [Zn(H2O)6]0.5 (p-BDC)0.5·(TTVP)0.5 (2) (m-H3BTC = 1,2,4-benzenetricarboxylic acid, p-H2BDC = 1,4-benzenedicarboxylic acid), have been synthesized and characterized. Structural analysis exhibits that complex 1 features one-dimensional (1D) chain structure, while complex 2 exists as a discrete monomeric structure. As anticipated, both complexes exhibit reversible photochromic properties under UV irradiation because of electron transfer (ET). More importantly, the photo-controlled luminescent properties and the potential application as inkless and erasable printing media are also explored.

Preparation, structure and properties of a novel one-dimensional erbium (III) complex

A novel one-dimensional erbium complex [ErL2(NO3)(H2O)2]n (HL = 2-picolinic acid) was synthesized by hydrothermal methods, and its crystal structure was determined by single crystal x-ray diffraction. The complex crystallize in monoclinic system, space group C2/c with a = 15.7525(5) Å, b = 11.4958(4) Å, c = 9.7977(3) Å, β = 102.862(3) º, V = 1729.72(10) Å3, C12H10ErN3O9, Mr = 507.49, Z = 4, Dc = 1.949 g•cm-3, F(000) = 972,  = 4.901 mm-1, S= 1.119, λ(MoKα) = 0.071073 nm, R = 0.0239 and wR = 0.0668. The 2-picolinic acid ligand adopts bidentate bridging coordination mode to connect adjacent erbium ions to form a one-dimensional chain structure. A series of properties of the complex were measured by solid-state photoluminescence, solid-state diffuse reflection and differential scanning calorimetry.

Crystal structure and characterization of a new one-dimensional copper(II) coordination polymer containing a 4-amino-benzoic acid ligand.

A CuII coordination polymer, catena-poly[[[aqua-copper(II)]-bis-(μ-4-amino-benz-o-ato)-κ2 N:O;κ2 O:N] monohydrate], {[Cu(pABA)2(H2O)]·H2O}n (pABA = p-amino-benzoate, C7H4NO2 -), was synthesized and characterized. It exhibits a one-dimensional chain structure extended into a three-dimensional supra-molecular assembly through hydrogen bonds and π-π inter-actions. While the twinned crystal shows a metrically ortho-rhom-bic lattice and an apparent space group Pbcm, the true symmetry is monoclinic (space group P2/c), with disordered Cu atoms and mixed roles of water mol-ecules (aqua ligand/crystallization water). The luminescence spectrum of the complex shows an emission at 345 nm, cf. 349 nm for pABAH.

Designing Optical Anisotropy: Silver-Aminoalkylpyridine Nitrate Complexes with Tunable Structures.

To introduce a design strategy for improving optical properties, two silver-amino alkylpyridine nitrate complexes, AgC6H8N3O3 and Ag2C14H20N6O6, were successfully synthesized using a recrystallization method. By employing polarizable π-conjugated [NO3-] ions, two types of pyridine ligands, and silver cations with a high affinity for pyridine, we obtained a one-dimensional chain structure with 4-aminomethylpyridine (AgC6H8N3O3) and a zero-dimensional molecular compound by introducing a relatively flexible aliphatic chain with 4-(2-aminoethyl)pyridine (Ag2C14H20N6O6). The compounds crystallize in the triclinic crystal system with the centrosymmetric P-1 space group, exhibiting a change in orientation between the π-conjugated system and the silver ion. Despite similar optical band gaps (3.69 eV for AgC6H8N3O3 and 3.73 eV for Ag2C14H20N6O6), AgC6H8N3O3 shows higher absorption in the 350-600 nm range. Electronic structure calculations support the ultraviolet absorption findings, suggesting that charge transfer with π-conjugated systems influences birefringence. Ag2C14H20N6O6 exhibits experimental birefringence (0.261@546.1 nm) surpassing that of AgC6H8N3O3 (0.212@546.1 nm), placing it among the highest recorded values within metal-pyridine incorporating nitrate complexes. The nonconventional orientation of π-conjugated [NO3-] ions contributes to this phenomenon, enhancing the action of free π-conjugated orbitals. This design strategy for micromodulating the alignment of the π-conjugated system promises to be an effective approach for enhancing optical properties, such as birefringence.

1D Cu(I)-based chiral organic-inorganic hybrid material with second harmonic generation and circular polarized luminescence.

In recent years, organic-inorganic hybrid materials have demonstrated exceptional performance in nonlinear optics, attracting widespread attention. However, there are relatively few examples of coordination compounds synthesized with Cu as the metal center that exhibit excellent nonlinear optical properties. In this study, we successfully synthesized a pair of enantiomers named R/S-Cu2I2 by reacting chiral ligands with CuI. The crystal structure reveals a one-dimensional copper-iodide chain structure built by Cu2I2 clusters, and its ordered arrangement in space provides not only a strong second harmonic generation (SHG) signal (1.24 × KDP) but also a large birefringence (0.15@1064 nm). Under excitation at 395 nm, the crystals exhibit red fluorescence peaked at 675 nm. The CD spectra of R/S-Cu2I2 show a distinct mirror-symmetric Cotton effect, and their CPL signals are corresponding and opposite in the emission range, with a maximum glum of approximately ±2.5 × 10-3. Theoretical calculations using density functional theory were also carried out to enhance our understanding of the correlation between their structures and optical properties.

Transverse-inertia-induced wave dispersion in plate–shell chains with a variable Poisson ratio

One-dimensional shell chain structures can cause stress wave dispersion, and the dispersion ability is mainly affected by the apparent elastic Poisson ratio of the unit cell composing the chain. In this study, a novel plate–shell chain structure with a variable Poisson ratio is proposed by combining bent plates and arc shells (BPAS). The dispersive wave propagation features in the BPAS chains under striker impact are studied theoretically, numerically, and experimentally. An equivalent continuum model of the unit cell under compression in a linear-elastic deformation regime is established, which contains two material parameters, i.e., the apparent elastic modulus and the apparent elastic Poisson ratio. It is found that the unit cell can reach a relatively large Poisson ratio by adjusting its structural parameters. A continuum-based wave propagation model considering transverse inertia is developed, and an explicit analytical solution is obtained to represent the dispersion wave propagation behavior within a linear-elastic deformation regime. The model can reasonably predict the force and velocity evolution features of the chains and is verified by the numerical/experimental tests. The results show that the BPAS chain with a large Poisson ratio exhibits superior wave dispersion performances. The underlying mechanism is that more impact energy is dispersed by the transverse movement of the cells in the BPAS chain. Increasing the aspect ratio of the unit cell can improve the wave dispersion ability of the BPAS chains, achieving a high attenuation of the stress wave and is helpful for impact mitigation.

Enormous electrothermal conductivity disparity in multiphase structure Sr4-xYxCo4O12-δ (x = 0–1.2) polycrystals

SrCoO3-δ system has garnered significant attention as the active material in solid-state thermal transistors. Herein, we have synthesized and characterized hexagonal, cubic, and ordered tetragonal Sr4-xYxCo4O12-δ (x = 0∼1.2) polycrystals with enormous electrothermal conductivity disparity. The hexagonal phase (H, SrCoO3-δ) exhibits quite low electrothermal conductivity (σ∼708.1 S m−1, κ∼0.982 W m−1 K−1) and considerable thermopower (175.4 μV K−1), resulting in lattice thermal conductivity dominates 98 % at 723 K. The one-dimensional chain structure (H) restricts hole carrier transmission, while the CoO6 octahedral unit induces phonon scattering (phonon mean free path in 0.206–0.261 nm). The cubic phase (CP, Sr3·6Y0·4Co4O12-δ) exhibits good electrothermal conductivity (σ∼8 × 104 S m−1 in 400∼650 K, κ∼2.718 W m−1 K−1 at 723 K) and thermopower close to zero, thus the carrier thermal conductivity contributing up to 46 %. The highly symmetrical CP phase with three-dimensional electron-phonon transport channels displays higher mobility (∼1505.7 cm2 V−1 s−1) and carrier concentration (Co4+). The ordered tetragonal phase (OT, Sr3YCo4O12-δ) exhibits an electrothermal performance between the hexagonal and cubic phases, due to oxygen-deficient CoO4.25 tetrahedral layers restricting the electron-phonon transport. The multiphase structure Sr4-xYxCo4O12-δ exhibits a significant contrast in electrothermal transport and holds promise as an active material for electron and phonon logic circuits.

From a Dy2 single-molecule magnet (SMM) to a 1D triangle-based Dy(III) chain SMM utilizing formate ions as bridging units

The reaction of Dy(NO3)2·6H2O with a Schiff base ligand N1,N3-bis(5-chlorosalicyladehyde)diethylenetriamine (H2bcsdt) afforded a dinuclear DyIII complex [Dy2(bcsdt)2(NO3)2] (1). The addition of HCOOH to the reaction system from which 1 was prepared generated a coordination polymer with the formula {[Dy3(bcsdt)3(HCOOH)(HCOO)(CO3)]·EtOH}n (2). Single-crystal X-ray diffraction analysis revealed that complex 2 possesses a one-dimensional chain structure based on a {[Dy3(bcsdt)3(HCOOH)(HCOO)(CO3)]·EtOH} repeating unit. In this unit, the three DyIII ions are connected by three oxygen atoms of one CO32– ion and display a nearly perfect triangle topology. The magnetic properties of 1 and 2 were investigated. They both exhibited slow relaxation of magnetization, indicative of single molecule magnet (SMM) behavior.

Nanoscale one-dimensional close packing of interfacial alkali ions driven by water-mediated attraction.

The permeability and selectivity of biological and artificial ion channels correlate with the specific hydration structure of single ions. However, fundamental understanding of the effect of ion-ion interaction remains elusive. Here, via non-contact atomic force microscopy measurements, we demonstrate that hydrated alkali metal cations (Na+ and K+) at charged surfaces could come into close contact with each other through partial dehydration and water rearrangement processes, forming one-dimensional chain structures. We prove that the interplay at the nanoscale between the water-ion and water-water interaction can lead to an effective ion-ion attraction overcoming the ionic Coulomb repulsion. The tendency for different ions to become closely packed follows the sequence K+ > Na+ > Li+, which is attributed to their different dehydration energies and charge densities. This work highlights the key role of water molecules in prompting close packing and concerted movement of ions at charged surfaces, which may provide new insights into the mechanism of ion transport under atomic confinement.

Syntheses, Structures, and Magnetic Properties of Three Cyano-Bridged FeII-MoIII Single-Molecule Magnets.

Three new cyano-bridged FeII-MoIII complexes assembled from the [MoIII(CN)7]4- unit, FeII ions, and three pentadentate N3O2 ligands, namely {[Fe2H3(dapab)2][Mo(CN)6]}n·2H2O·3.5MeCN (1), [Fe(H2dapb)(H2O)][Fe(Hdapb)(H2O)][Mo(CN)6]·4H2O·3MeCN (2), and [Fe(H2dapba)(H2O)]2[Mo(CN)7]·6H2O (3) (H2dapab = 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone), H2dapb = 2,6-diacetylpyridine bis(benzoylhydrazone), H2dapba = 2,6-diacetylpyridine bis(4-aminobenzoylhydrazone)), have been synthesized and characterized. Single-crystal structure analyses suggest that complex 1 contains a one-dimensional (1D) chain structure where two FeII ions are bridged by the in situ generated [MoIII(CN)6]3- unit through two trans-cyanide groups into trinuclear Fe2IIMoIII clusters that are further linked by the amino of the ligand into an infinite chain. Complexes 2 and 3 are cyano-bridged Fe2IIMoIII trinuclear clusters with two FeII ions connected by the [MoIII(CN)6]3- and [MoIII(CN)7]4- units, respectively. Direct current magnetic studies confirmed the ferromagnetic interactions between the cyano-bridged FeII and MoIII centers and significant easy-axis magnetic anisotropy for all three complexes. Furthermore, complexes 1-3 exhibit slow magnetic relaxation under a zero dc field, with relaxation barriers of 42.3, 21.6, and 14.4 K, respectively, making them the first examples of cyano-bridged FeII-MoIII single-molecule magnets.

Crystal structure and thermally enhanced photoluminescence in Eu(III) coordination polymers self-assembled from p-nitrobenzoic acid

Luminescent thermal quenching is a very troublesome thing for the practical application of luminescent materials, but also is a very common phenomenon. In theory, artificially reducing the number of quenching group around the luminescent lanthanide ion can effectively enhance the luminescence of lanthanide luminescent materials. In this paper, {[Eu2(NBA)6(H2O)4]∙H2O}n [Eu-NBA, NBA = p-nitrobenzoic acid] coordination polymers containing abundant coordination and interstitial water molecules were synthesized via hydrothermal methods. The chemical composition, crystal structures, and thermal stability of Eu-NBA coordination polymers were systemically investigated by Frontier-transfer infrared (FTIR) spectra, single-crystal X-ray diffraction and thermogravimetric analysis. X-ray diffraction analysis results revealed that Eu-NBA coordination polymers were crystallized into one-dimensional (1D) chain structures, where the adjacent Eu3+ ions were linked together by bidentate and/or tetradentate bridging carboxylate groups of the NBA ligands. The temperature-dependent photoluminescence spectra revealed that the shape and intensity of the luminescence spectra strongly depended on the coordination environment around Eu3+, and significant luminescent thermal enhancement was observed. These experimental results provided useful theoretical support for further understanding of the luminescence enhancement mechanism of lanthanide coordination polymers.

Oriented assembly of hydrophilic nanochains modified by porous zirconium-based coordination polymers for glycopeptides analysis

Mass spectrometry (MS)-based glycoproteomics research requires additional sample pretreatment to improve the effective identification of low-abundance glycopeptides without interference from non-glycoproteins. Herein, an attractive strategy using resorcinol-formaldehyde (RF) resin and zirconium-based coordination polymer (Zr-BCP) was established to prepare one-dimensional porous coordination polymer composites for glycopeptide enrichment before MS analysis. The obtained Fe3O4@RF@Zr-BCP nanochains feature excellent magnetic response (42.26 emu/g), high hydrophilicity (16.0°), and large specific surface area (140.84 m2/g), which provides abundant affinity sites for specific capture of glycopeptides. The materials exhibit outstanding performance in the enrichment of glycopeptides in terms of sensitivity (15 fmol/μL IgG), selectivity (1:200, molar ratio of IgG/BSA), loading capacity (200 mg/g) and recovery (106.4 ± 3.5%). In addition, the developed method based on Fe3O4@RF@Zr-BCP has been successfully applied to capture glycopeptides in tryptic digest of mouse teratoma cell extracts. It is worth emphasizing that compared with dispersed nanoparticles, the one-dimensional chain structure brings extraordinary reusability to Fe3O4@RF@Zr-BCP nanochains, which is conducive to the rapid cyclic enrichment of glycopeptides. This present work provides a potential enrichment platform for comprehensive glycoprotein analysis, and opens a new avenue for the application of oriented-assembly nanochains.

One-Dimensional Coordinated Polymers of Tetraphenylethene Pyridine and Copper-Iodide for Fluorescence Detection of Nitroaromatic Explosives.

The spatial arrangement of molecules plays a crucial role in determining the macroscopic properties of functional materials. Coordinated polymers (CPs) formed by self-assembly of organic isomeric ligands and metals offer unique performance characteristics. In this study, we present the investigation of a one-dimensional CP, named CIT-E, composed of tetraphenylethene pyridine derivative (TPE-2by-2-E) ligands and cuprous iodide. The resulting CP exhibits a one-dimensional bead chain structure with exceptional thermal and chemical stability. By leveraging the competitive absorption between CIT-E and the explosive analog 2,4-dinitroaniline, we achieve detection of the explosive through changes in the absorption intensity of the excitation light source and subsequent fluorescence response. The CP demonstrates high selectivity and anti-interference ability in detecting 2,4-dinitroaniline in aqueous solution, with a detection linear range of 0.1 μM to 300 μM and a detection limit of 0.05 μM, surpassing the national third-level emission standard. These findings highlight the potential of CP CIT-E as a promising material for the detection of explosive nitroaromatic compounds.

α- and β-(C4H5N2O)(IO3)·HIO3: Two SHG Materials Based on Organic-Inorganic Hybrid Iodates.

Organic-inorganic hybrid nonlinear optical (NLO) materials are highly anticipated because of the integration of both merits of the organic and inorganic moieties. Herein, the 2-pyrimidinone cation (C4H5N2O)+ has been incorporated into the iodate system to form two polymorphic organic-inorganic hybrid iodates, namely, α- and β-(C4H5N2O)(IO3)·HIO3. They crystallize in different polar space groups (Ia and Pca21), and their structures feature one-dimensional (1D) chain structures composed of (C4H5N2O)+ cations, IO3- anions, and HIO3 molecules interconnected via hydrogen bonds. α- and β-(C4H5N2O) (IO3)·HIO3 exhibit strong and moderate second-harmonic-generation (SHG) responses of 6.4 and 0.9 × KH2PO4 (KDP), respectively, the same band gaps of 3.65 eV, and high powder laser-induced damage threshold (LIDT) values [51 and 57 × AgGaS2 (AGS)]. The results of theoretical calculations revealed that the large SHG effect of α-(C4H5N2O)(IO3)·HIO3 originated from the IO3 and HIO3 groups. This work indicates that (C4H5N2O)+ is a potential group for designing new NLO materials with brilliant optical performances.