Crystal Structure Analysis Research Articles

Degradation of Orange G, Acid Blue 161, and Brillant Green Dyes Using UV Light‐Activated GA–TiO2–Cd Composite

AbstractIn this study, photocatalysts with high photocatalytic activity performance are synthesized by synthesizing graphene aerogel‐supported, cadmium‐doped TiO2 composites by hydrothermal method for the effective degradation of organic dyes in wastewater. Here, GA–TiO2–Cd is investigated as a photocatalyst for the degradation of toxic dyes named Orange G, Acid Blue 161, and Brilliant Green in the UV part of the light spectrum. As a result of the experiments, it is observed that the effective decomposition of organic dyes is due to graphene aerogel (GA) and cadmium‐doped TiO2 nanoparticles. The results show that for 20 ppm solutions of Orange G, Acid Blue 161, and Brilliant Green, dyes are removed at approximately 81.075%, 84.15%, and 95.18% in 120 min. The morphology and elemental analysis of the synthesized composites are determined using SEM‐EDS, crystal structure analysis by XRD, chemical bond analysis by FTIR, optical properties by UV‐Vis‐NIR spectrophotometry, and thermal resistance by TGA analysis.

Synthesis and catalytic activity of half‐sandwich iridium complexes with acylhydrazone ligands for N‐alkylation of hydrazides under mild conditions

A new [Cp*IrClL] half‐sandwich iridium complex was successfully synthesized by coordinating an acylhydrazone ligand with [Cp*IrCl2]2, followed by comprehensive characterization using various spectroscopic and analytical techniques. Complex 3 was subjected to crystal structure analysis, revealing that the acylhydrazone ligand coordinates with the iridium through bidentate coordination involving the imidolate oxygen and imine nitrogen atoms. This interaction resulted in the formation of a pseudo‐octahedral geometry with the iridium center. The iridium complexes 1–4, which are stable in the presence of air and moisture, exhibit significant catalyst performance in the N‐alkylation reactions of hydrazides under gentle reaction conditions. This iridium complex catalyzes various types of alcohols to undergo N‐alkylation reactions with acyl hydrazides via a one‐pot method, yielding diverse N‐alkylated hydrazide derivatives. The catalyst displayed exceptional catalytic efficiency, a broad variety of substrates, and gentle reaction conditions, indicating its significant potential for industrial applications.

Observation of Chiral Channels in Helical Covalent Organic Frameworks.

Unraveling the mechanism of chirality transfer across length scales is crucial to the rational development of functional materials with hierarchical chirality. The key obstacle is the lack of structural information, especially at the mesoscopic level. We report herein the structural identification of helical covalent organic frameworks (heliCOFs) with hierarchical chirality, which integrate molecular chirality, channel chirality, and morphology chirality into one crystalline entity. Specifically, benefiting from the highly ordered structure of heliCOFs, the existence of chiral channels at the mesoscopic level has been confirmed by electron crystallography, and the handedness of these chiral channels has been directly determined through the stereopair imaging technique. Accordingly, the chirality transfer in heliCOFs from microscopic to macroscopic levels could be rationalized with a layer-rotating model that has been supported by both crystal structure analysis and theoretical calculations. Observation of chiral channels in heliCOFs not only provides unprecedented data for the understanding of the chirality transfer process but also sheds new light on the rational construction of highly ordered polymeric materials with hierarchical chirality.

Substrate Controlled [3+3] Relay Catalytic Cyclization of α‐(3‐Isoindolinonyl) Propargylic Alcohols with 5‐Aminoisoxazoles

AbstractTwo different skeletons have been constructed by cyclization of α‐(3‐isoindolinonyl) propargylic alcohols with 5‐aminoisoxazoles bearing different N‐substituents under the relay catalysis of Brønsted acid and Lewis acid. This method provided spiro‐isoindolinone‐dihydropyridines with moderate to high yields (up to 99 %) as well as isoxazolo[4,5‐b]pyridines in moderate to good yields (up to 86 %). The structures of two products were determined by X‐ray crystal structural analyses. Moreover, fluorescence testing proved that one of the isoxazolo[4,5‐b]pyridines exhibited aggregation induced emission (AIE) effect. Finally, the control experiments revealed the possible reaction mechanism.

Crystal structure and Hirshfeld surface analysis of 5-hydroxypentanehydrazide

Carboxyhydrazides are widely used in medicinal chemistry because of their medicinal properties and many drugs have been developed containing this functional group. A suitable intermediate to obtain potential hydrazide drug candidates is the title compound 5-hydroxypentanehydrazide, C5H12N2O2 (1). The aliphatic compound can react both via the hydroxyl and hydrazide moieties forming derivatives, which can inhibit Mycobacterium tuberculosis catalase-peroxidase (KatG) and consequently causes death of the pathogen. In this work, the hydrazide was obtained via a reaction of a lactone with hydrazine hydrate. The colourless prismatic single crystals belong to the orthorhombic space group Pca21. Regarding supramolecular interactions, the compound shows classic medium to strong intermolecular hydrogen bonds involving the hydroxyl and hydrazide groups. Besides, the three-dimensional packing also shows weak H...H and C...H contacts, as investigated by Hirshfeld surface analysis (HS) and fingerprint plots (FP).

‘Charge Reverse’ Halogen Bonding Contacts in Metal-Organic Multi-Component Compounds: Antiproliferative Evaluation and Theoretical Studies

Two new metal–organic multi-component compounds of Ni(II) and Co(II), viz. [Ni(3-CNpy)2(H2O)4]ADS·2.75H2O (1) and [Co(3-CNpy)2(H2O)4](4-ClbzSO3)2 (2) (3-CNpy = 3-cyanopyridine, ADS = anthraquinone-1,5-disulfonate, 4-ClbzSO3 = 4-chlorobenzenesulfonate), were synthesized and characterized using single crystal XRD, TGA, spectroscopic (IR, electronic) and elemental analyses. Both the compounds crystallize as multi-component compounds of Ni(II) and Co(II), with uncoordinated ADS and 4-ClbzSO3 moieties in the crystal lattice, respectively. Crystal structure analyses revealed the presence of antiparallel nitrile···nitrile and π-stacked assemblies involving alternate coordinated 3-CNpy and uncoordinated ADS and 4-ClbzSO3 moieties. Moreover, unconventional charge reverse Cl∙∙∙N halogen bonding contacts observed in compound 2 provide additional reinforcement to the crystal structure. Theoretical calculations confirm that the H-bonding interactions, along with anion–π(arene) and anion–π(CN) in 1 and π–π, antiparallel CN···CN and charge reverse Cl···N halogen bonds in 2, play crucial roles in the solid state stability of the compounds. In vitro anticancer activities observed through the trypan blue cell cytotoxicity assay reveal that the compounds induce significant concentration dependent cytotoxicity in Dalton’s lymphoma (DL) cancer cells, with nominal effects in normal healthy cells. Molecular docking studies reveal that the compounds can effectively bind with the active sites of anti-apoptotic proteins, which are actively involved in cancer progression.

Photocatalytic Activity of BaAl2O4 for Water Purification.

Degradation of dyes under natural light sources is one of the most active research areas in basic science for greener technology. In this context, the photocatalytic activity of semiconductors has received massive attention in solving water treatment-related issues as these possess enormous potential for degrading organic impurities. Here, we report that barium aluminate (BaAl2O4, BAO), which has been extensively studied for photoluminescence applications, is found to be a highly potent candidate for photocatalytic activities. We have explored the degradation of dyes (meant for water purification) by using the photocatalytic properties of pure and Dy- and Yb-codoped BAO. Crystal structure, electron microscopy, and Raman analysis of the autocombustion-synthesized pure and codoped BAO samples revealed significant morphological changes such as increased particle size and stabilization of rod-like structures. UV-vis absorbance measurements confirm the presence of multiple bandgaps in the BAO samples, which is substantiated by X-ray absorption spectroscopy measurements. Photocatalytic degradation studies of methylene blue (MB) dye (with different catalyst concentrations, dopings, and MB dye concentrations) have been carried out by using BAO. The kinetics of the photocatalytic degradation measurements has been explained by the Boltzmann distribution function, and the fastest (in less than 40 min), with more than 99% degradation of MB impurity, is reported here for the first time in BAO compounds. Synthesized BAO samples show excellent cyclic stability, which is essential for their potential applications in environmental remediation. The trade-off between the enhancement of surface area and increased particle size is considered the key parameter for controlling the photocatalytic performance of the BAO catalyst after Dy and Yb codopings.

Crystal structure and Hirshfeld surface analysis of dimethyl 4′-bromo-3-oxo-5-(thiophen-2-yl)-3,4,5,6-tetrahydro-[1,1′-biphenyl]-2,4-dicarboxylate

In the title compound, C20H17BrO5S, molecules are connected by intermolecular C—H...S hydrogen bonds with R 2 2(10) ring motifs, forming ribbons along the b-axis direction. C—H...π interactions consolidate the ribbon structure while van der Waals forces between the ribbons ensure the cohesion of the crystal structure. According to a Hirshfeld surface analysis, H...H (40.5%), O...H/H...O (27.0%), C...H/H...C (13.9%) and Br...H/H...Br (11.7%) interactions are the most significant contributors to the crystal packing. The thiophene ring and its adjacent dicarboxylate group and the three adjacent carbon atoms of the central hexene ring to which they are attached were refined as disordered over two sets of sites having occupancies of 0.8378 (15) and 0.1622 (15). The thiophene group is disordered by a rotation of 180° around one bond.

Trueness, physical properties, and surface characteristics of additive-manufactured zirconia crown

ObjectiveThis study aimed to conduct a comparison of trueness and physical and surface properties among five distinct types of additive manufactured (AM) zirconia crowns and zirconia crowns produced using the subtractive manufacturing (SM). Material and methodsZirconia crowns were fabricated using five distinct techniques, each varying in the method of slurry transfer and photocuring source. Each experimental group utilized either one of the four digital light processing (DLP)-based techniques (DLP spreading, DLP spreading gradation, DLP vat and DLP circular spreading) or the stereolithography (SLA)-based technique (SLA spreading). The control (CON) group employed SM. To assess accuracy, trueness was measured between the scan and reference data. To analyze the physical properties, voids were examined using high-energy spiral micro-computed tomography scans, and the crystal structure analysis was performed using X-ray diffraction (XRD). Surface roughness was assessed through laser scanning microscopy. ResultsDifferences in the trueness of internal surfaces of crowns were found among the groups (P < 0.05). Trueness varied across the measurement surfaces (occlusal, lateral, and marginal) in all the groups except for the DLP spreading gradation group (P < 0.05). Voids were observed in all AM groups. All groups showed similar XRD patterns. All AM groups showed significantly greater surface roughness compared to the CON group (P < 0.001). ConclusionThe AM zirconia crowns showed bubbles and a rougher surface compared to the SM crowns. All groups exhibited typical zirconia traits and trueness levels within clinically acceptable limits, suggesting that current zirconia AM techniques could be suitable for dental applications.

Color manipulation of mechanoluminescence and photoluminescence from CaZnOS:ZnS:Mn2+ heterocompound controlled by ion doping concentration

Calcium zinc oxysulfide (CaZnOS) and cognate semiconductors are emerging materials possessing exceptional piezoluminescent properties. A CaZnOS:ZnS binary heterocompound doped with various Mn2+ concentrations from 0.1 to 8% has been prepared using the solid-state reaction method. The structural, chemical and optical properties of the obtained powders are studied. Their crystal structure and compositional analyses have shown two stable main phases of ZnS and CaZnOS so that the powder generally appears as a binary compound of the ZnS:Mn2+ and CaZnOS:Mn2+ particles. The role of ZnS:Mn2+ and CaZnOS:Mn2+ phases on mechanoluminescence (ML) and photoluminescence (PL) is particularly investigated. The luminescence spectra show the contribution of ZnS:Mn2+ and CaZnOS:Mn2+ as particles of yellow and red colors, respectively. When increasing the Mn2+ concentration, a redshift of the luminescence spectra and optical bandgap is observed due to a rising contribution of the CaZnOS:Mn2+ phase. By this means, a bright luminescence along with color manipulation from yellow to red is achieved. So, by capturing long-exposure photographs of ML from the powder in a flexible film, the powder samples are used to write a pattern. The brightest emission is observed up to 0.8% of Mn2+, while the luminescence gradually lowers at higher dopant concentrations. The experimental base shows that a binary compound containing highly efficient novel CaZnOS and conventional ZnS doped with Mn2+ ions is a proper way to develop intense multicolor ML ranging from yellow to red emission.

A Nickel-doped, lanthanum gallium germanate-based phosphor as an ultra-broadband short-wavelength infrared region emitter for optical imaging

Short-wavelength infrared region light source (SWIR, λ = 1000–2000 nm) is useful for optical imaging of biological tissues for lack of auto-fluorescence, low intrinsic absorption, and low scattering. Here, we report the synthesis, characterization, and mechanistic studies of a Ni2+-doped, lanthanum gallium germanate-based phosphor, La3Ga5GeO14:Ni2+, that emits SWIR with an ultra-broad bandwidth emission of 1000–2000 nm, a full-width at half maximum (FWHM) of 340 nm, which covers near infrared-II and III regions. The analysis of crystal structure suggests that Ga3+ ions in [GaO6] octahedron lattices are replaced by Ni2+ ions, possibly due to the similar radius shared by both ions. The observed ultra-broadband SWIR luminescence with large Stokes shift is most likely originated from the influence of a strong crystal field on the extent of the cleavage of energy levels of Ni2+ ions, which is supported by the charge density data of [GaO6] octahedra in La3Ga5GeO14 derived from state density functional calculation. A SWIR pc-LED was constructed by packaging the La3Ga5GeO14:Ni2+ phosphor with a near-ultraviolet LED chip, and its potential application in optical imaging of human bodies was explored.

Supramolecular assembly in Cu(II) and Zn(II) compounds with pyridine and anthraquinone-1,5-disulfonate: Experimental and theoretical analysis

Two new multi-component coordination compounds of Cu(II) and Zn(II) viz. [Cu(py)2(H2O)4]ADS·2H2O (1) and [Zn(4-CNpy)2(H2O)4]ADS·2H2O (2) (py = pyridine, 4-CNpy = 4-cyanopyridine, ADS = anthraquinone-1,5-disulfonate) have been synthesized in aqueous media at room temperature and characterized using elemental and spectroscopic analyses (FT-IR, electronic), TGA and single crystal X-ray diffraction techniques. Both the compounds crystallize as metal–organic multi-component compounds containing complex cationic moieties along with uncoordinated anionic ADS moieties in the crystal structures. Crystal structure analysis of 1 reveals the stabilisation of the layered assembly of the compound assisted by CH⋯O, OH⋯O hydrogen bonding and π-stacking interactions. Antiparallel CN⋯CN and aromatic π-stacking interactions provide rigidity to the crystal structure of compound 2. In addition, enclathration of lattice water molecules within the supramolecular cavity of 2 provides additional reinforcement to the crystal structure. We have carried out theoretical investigations to analyze π-stacking, H-bonding and antiparallel CN···CN non-covalent interactions observed in the compounds using DFT calculations, quantum theory of atoms in molecules (QTAIM) and non-covalent interaction (NCI) plot index computational tools. The binding energies of the supramolecular assemblies are quite significant due to the ion-pair nature of the interactions which lack directionality; however, the aforementioned weaker non-covalent interactions play crucial roles in the final arrangement of molecules in the solid state due to their directional nature.

Needlestick-Stimulation-Induced Conversion of Short-Wave Infrared-Light Transparency Using a Liquescent Radical Anion.

A liquescent salt consisting of a 7,7,8,8-tetracyanquinodimethane (TCNQ) radical anion and a tetra-n-decylammonium ion, 1+•TCNQ•-, exhibits rapid changes in the short-wave infrared (SWIR) light transparency at 1000-1400nm upon the application of a one-shot needlestick-stimulus. Radical anion salt 1+•TCNQ•- transforms from a blue solid to a green liquid at 90°C without decomposition under aerated conditions, and remains in the liquid state upon cooling to 70°C. After applying pressure with a needlestick on a cover glass at 70°C, the liquid transforms rapidly into the solid state over a timescale of seconds across a centimeter scale of area. Along with the liquid-solid transition, the SWIR-light transparency at 1200nm completely switches from the "on" to the "off" states. Experimental results, such as electronic spectra and crystal structure analysis, indicates that the SWIR-light absorption in the solid state is due to the existence of a slipped-stacking π-dimer structure for TCNQ•-. The rapid rearrangement is induced by the formation of the π-dimer structures from the monomers of TCNQ•- and the subsequent generations of the solid-state seed.

Synthesis, spectroscopic, DFT, anticancer evaluation and enzyme inhibition studies of platinum(II) complexes with 1-methyl-1H-1,2,3,4-tetrazole-5-thiol and phosphine ligands: Crystal structure of [Pt(mtzt)2(dppe)]

A number of Pt(II) complexes of 1-methyl-1H-1,2,3,4-tetrazole-5-thiol (Hmtzt) with phosphine ligands have been prepared and characterized and then evaluated as potential anti-cancer and ALP enzyme inhibitor agents. The complex [Pt(mtzt)2]2 was prepared by the reaction of 1-methyl-H1-tetrazole-5-thiol (Hmtzt) with K2PtCl4. This complex was treated with equivalent molar amounts of diphosphine ligands to afford complexes of the type [Pt(mtzt)2(PPh2(CH2)nPPh2)] in good yield, {PPh2(CH2)nPPh2, where n = 1 (dppm), n = 2 (dppe), n = 3 (dppp), n = 4 (dppb) and (PPh2((C5H4)2Fe)PPh2) (dppf)}. The prepared complexes were characterized by elemental analysis, IR, 1H-{31P} and 31P-{1H} NMR spectroscopy. The resulting data suggested that the prepared complexes were mononuclear with chelating diphosphines while the mtzt ligands were monodentate coordinating via the sulfur atom to give a square planner arrangement around the Pt(II) ion. This was confirmed by a single crystal structural analysis of the [Pt(mtzt)2(dppe)] complex. The Pt(II) complexes underwent structural optimization through the utilization of the DMol3 tool within the material studio package. A comparison of the results of molecular modelling with those of the X-ray structural analysis indicated that the structures were almost identical. The free ligand and two selected complexes were tested for inhibition activity against an alkaline phosphatase (ALP) enzyme, which was found to be active inhibitors, and the inhibition rate (37–88 %) range. Furthermore, the anticancer activity of the complexes (1, 3, and 6) was tested against human liver cancer (HepG2). The results showed that the prepared complexes have moderate activity but are lower than cis-platin. Complex 1 has the highest activity with an IC50 of 34.78 ± 1.75 M against the HepG2 cell line..

Energetic Features of H-Bonded and π-Stacked Assemblies in Pyrazole-Based Coordination Compounds of Mn(II) and Cu(II): Experimental and Theoretical Studies

Two new coordination compounds comprising Mn(II) and Cu(II) viz. [Mn(bz)2(Hdmpz)2(H2O)] (1) and [Cu(crot)2(Hdmpz)2] (2) (where, bz = benzoate; crot = crotonate; Hdmpz = 3, 5-dimethyl pyrazole) were synthesized and characterized. The characterization involved a single crystal X-ray diffraction technique, FT-IR spectroscopy, electronic spectroscopy, TGA, and elemental analyses. Compounds 1 and 2 crystallize as mononuclear entities of Hdmpz with penta-coordinated Mn(II) and hexa-coordinated Cu(II), respectively. These complexes exhibit distorted trigonal bipyramidal and distorted octahedral geometries, respectively. A crystal structure analysis of compound 1 elucidates the existence of C–H⋯π and π-stacking interactions alongside O–H⋯O, N–H⋯O, and C–H⋯O H-bonding interactions contributing to the stabilization of the compound’s layered assembly. Similarly, in compound 2, the crystal structure stability is attributed to the presence of hydrogen bonding in conjugation with π-stacking interactions. We conducted theoretical investigations to analyze π⋯π, H-bonding, and antiparallel CH···π non-covalent interactions observed in compounds 1 and 2. DFT calculations were performed to find out the strength of these interactions energetically. Moreover, QTAIM and non-covalent interaction (NCI) plot index theoretical tools were employed to characterize them and evaluate the contribution of the H-bonds.

Heteroatom Promoted Polyhexagonal Saddle-Shaped Molecular Structure and Its Supramolecular Coassembly with C60.

Molecules with curved architecture can exhibit unique opto-electronic properties due to the concave-convex π-surface. However, synthesizing negatively curved saddle-shaped aromatic systems has been challenging due to the internal structural strain. Herein, we report the facile synthesis of two polyhexagonal molecular systems, 1 and 2, with saddle shape geometry by judiciously varying the aromatic moiety, avoiding the harsh synthetic methods as that of heptagonal aromatic saddle systems. The unique geometry preferences of B, N, and S furnish suitable curvature to the molecules, featuring saddle shape. The saddle geometry also enables them to interact with fullerene C60, and the supramolecular interactions of fullerene C60with 1 and 2 modify their optoelectronic properties. Crystal structure analysis reveals that 1, with a small π-surface, forms a double columnar array of fullerenes in the solid state. In contrast, 2 with a large π-surface produces a supramolecular capsule entrapping discrete fullerene dimer. The intermolecular interactions between B, N, S, and the aryl-π surface of the host and C60 guest are the stabilizing factors for creating these supramolecular structures. Comprehensive computational, optical, electrochemical, and Raman spectroscopic studies establish the charge transfer interactions between B-N doped heterocycle host and fullerene C60 guest.

Crystal structure analysis of self-catalyzed InAs nanowire grown by MOCVD

We studied the crystal structure of self-catalyzed InAs nanowires with different diameters grown on Si Substrate by metal-organic chemical vapor deposition (MOCVD) and found that oxidation degree and nanowire diameter directly affect the lattice structure of InAs nanowire. In the non-oxidized state of InAs nanowires, when the diameter is greater than 160 nm, the lattice structure is mainly cubic zinc blende (ZB) structure. When the diameter is between 121 nm and 80 nm, ZB structure and hexagonal wurtzite (WZ) structure coexist. When the diameter is less than 66 nm, the lattice structure is mainly WZ structure. In the fully oxidized state of InAs nanowires, a stable layer of In2O3 is formed on its surface, and InAsO4 will be formed inside due to infiltrated oxygen atoms. When InAs nanowires are made into nanoelectronic devices as the core material, if oxidation is not prevented, InAs material with excellent electrical conductivity will also become InAsO4.

Crystal structure and Hirshfeld surface analysis of ethyl 2-(7-chloro-3-methyl-2-oxo-1,2-di-hydro-quinoxalin-1-yl)acetate.

The quinoxaline moiety in the title mol-ecule, C13H13ClN2O3, is almost planar (r.m.s. deviation of the fitted atoms = 0.033 Å). In the crystal, C-H⋯O hydrogen bonds plus slipped π-stacking and C-H⋯π(ring) inter-actions generate chains of mol-ecules extending along the b-axis direction. The chains are connected by additional C-H⋯O hydrogen bonds. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (37.6%), H⋯O/O⋯H (22.7%) and H⋯Cl/Cl⋯H (13.1%) inter-actions.

Crystal structure and Hirshfeld surface analysis of 4,4'-di-meth-oxy-biphenyl-3,3',5,5'-tetra-carb-oxy-lic acid dihydrate.

In the crystal of the title compound, C18H14O10·2H2O, the arene rings of the biphenyl moiety are tilted at an angle of 24.3 (1)°, while the planes passing through the carboxyl groups are rotated at angles of 8.6 (1) and 7.7 (1)° out of the plane of the benzene ring to which they are attached. The crystal structure is essentially stabilized by O-H⋯O bonds. Here, the carboxyl groups of neighbouring host mol-ecules are connected by cyclic R 2 2(8) synthons, leading to the formation of a three-dimensional network. The water mol-ecules in turn form helical supra-molecular strands running in the direction of the crystallographic c-axis (chain-like water clusters). The second H atom of each water mol-ecule provides a link to a meth-oxy O atom of the host mol-ecule. A Hirshfeld surface analysis was performed to qu-antify the contributions of the different inter-molecular inter-actions, indicating that the most important contributions to the crystal packing are from H⋯O/O⋯H (37.0%), H⋯H (26.3%), H⋯C/C⋯H (18.5%) and C⋯O/O⋯C (9.5%) inter-actions.

Characterization, crystal structure and stability analysis of dianhydrodulcitol polymorphs

1,2:5,6-Dianhydrogalactitol (DAG), an anticancer drug with different crystal structures, is investigated in order to get a comprehensive understanding of its polymorphism. Two polymorphs of DAG were prepared by different methods using DAG form I as the starting material. The formation of new crystal forms was confirmed by means of PXRD and other characterization methods. The single crystals of three polymorphs, including a new discovered crystal form II, were prepared and studied. The crystal structure of the new crystal form II was determined by single crystal X-ray diffraction, and the difference in hydrogen bonding structure of the DAG polymorphs was analyzed. The intermolecular interactions of the DAG polymorphs were studied by Hirshfeld surface analysis. The stability relationship between three polymorphs under different conditions was studied. DAG form I is stable at low temperatures and form III is more stable at high temperatures. Form II is a metastable crystal form and can be transformed into the other two crystal forms by solvent-mediated crystallization.