Crystal Growth & Design最新文献

{"title":"Stacking Interactions in Indomethacin Solid-State Forms.","authors":"Nazanin Fereidouni, Marwah Aljohani, Andrea Erxleben","doi":"10.1021/acs.cgd.4c01507","DOIUrl":"10.1021/acs.cgd.4c01507","url":null,"abstract":"<p><p>Stacked structures with strong dispersion forces between stack neighbors often lead to anisotropic crystal growth and needlelike morphologies. The crystal structures of a new cocrystal and a molecular salt of indomethacin (IND) are reported: IND·MOA and IND·POBA·0.5H₂O (MOA = <i>p</i>-methoxyaniline, POBA = 4-phenoxybenzylamine). In both structures, the IND and coformer molecules/ions are stacked and IND adopts the unusual conformation found in the α-polymorph of pure IND, resulting in a relatively short distance of about 3 Å between the methyl group and the C1'-atom of the chlorophenyl ring. While IND·MOA and IND·POBA·0.5H₂O both crystallize as needles like α-IND, the weaker stacking interactions of the coformer in the IND·MOA cocrystal lead to shorter and thicker needles. Amorphous IND prepared by milling recrystallizes to the stable γ-polymorph without the metastable α-form being detected. When IND is milled in the presence of 2.5 wt % MOA, the amorphous phase converts to α-IND. The effect of small amounts of the coformer on the recrystallization route is attributed to a templating effect of the cocrystal formed during milling and/or the facilitation of the conversion to the α-phase conformation.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1776-1784"},"PeriodicalIF":3.2,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11926784/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143690472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stacking Interactions in Indomethacin Solid-State Forms","authors":"Nazanin Fereidouni,&nbsp;Marwah Aljohani and Andrea Erxleben*,&nbsp;","doi":"10.1021/acs.cgd.4c0150710.1021/acs.cgd.4c01507","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01507https://doi.org/10.1021/acs.cgd.4c01507","url":null,"abstract":"<p >Stacked structures with strong dispersion forces between stack neighbors often lead to anisotropic crystal growth and needlelike morphologies. The crystal structures of a new cocrystal and a molecular salt of indomethacin (IND) are reported: IND·MOA and IND·POBA·0.5H₂O (MOA = <i>p</i>-methoxyaniline, POBA = 4-phenoxybenzylamine). In both structures, the IND and coformer molecules/ions are stacked and IND adopts the unusual conformation found in the α-polymorph of pure IND, resulting in a relatively short distance of about 3 Å between the methyl group and the C1′-atom of the chlorophenyl ring. While IND·MOA and IND·POBA·0.5H₂O both crystallize as needles like α-IND, the weaker stacking interactions of the coformer in the IND·MOA cocrystal lead to shorter and thicker needles. Amorphous IND prepared by milling recrystallizes to the stable γ-polymorph without the metastable α-form being detected. When IND is milled in the presence of 2.5 wt % MOA, the amorphous phase converts to α-IND. The effect of small amounts of the coformer on the recrystallization route is attributed to a templating effect of the cocrystal formed during milling and/or the facilitation of the conversion to the α-phase conformation.</p><p >Low levels of <i>p</i>-methoxyaniline affect the recrystallization pathway of milled, amorphous indomethacin, which is attributed to traces of cocrystal formation during milling.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1776–1784 1776–1784"},"PeriodicalIF":3.2,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.cgd.4c01507","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid Crystallization of Zeolites with Controllable Defects: Disentangling Fluoride Concentration and pH Using NH4F","authors":"Muhammad Ali Shah,&nbsp;Taras Nagornyy,&nbsp;Success Eghosa Aiwekhoe,&nbsp;Seungbo Hong,&nbsp;Nhan Huu Huy Tran,&nbsp;Song Luo,&nbsp;Zhu Chen,&nbsp;Scott M. Auerbach* and Wei Fan*,&nbsp;","doi":"10.1021/acs.cgd.4c0161310.1021/acs.cgd.4c01613","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01613https://doi.org/10.1021/acs.cgd.4c01613","url":null,"abstract":"<p >Zeolite synthesis is typically conducted either under basic conditions or in neutral fluoride media using hydrofluoric acid (HF). While basic (OH^–) conditions generally result in faster zeolite crystallization, they can also increase the likelihood of framework defects and crystal intergrowths. In contrast, synthesis in neutral fluoride media tends to produce fewer defects because fluoride balances positive charges from structure-directing agents. However, this method often requires significantly longer crystallization times and involves the handling of dangerous HF. In the present study, we pursue the best of both synthesis conditions, rapid syntheses with controllable defect concentrations, by disentangling of mineralizing agent and charge-balancing agent using ammonium fluoride (NH₄F) as an alternative to HF. We have investigated the use of NH₄F in the syntheses of siliceous and aluminum-containing zeolite A (LTA, small pore), ZSM-5 (MFI, medium pore), and siliceous Beta(*BEA, large pore). The crystallization times of all four zeolites decreased substantially with an increasing NH₄F concentration. Crystallization times were reduced from 24 to 4 h (Si-LTA), 96 to 36 h (Al-LTA), 240 to 6 h (ZSM-5), and 24 to 3 h (Si-*BEA). Additionally, increasing the NH₄F concentration in the synthesis mixtures decreases the defect densities of siliceous zeolites. Raman spectroscopy, along with ²⁹Si MAS NMR, ¹⁹F MAS NMR, ¹³C MAS NMR, and fluorine elemental analysis of Si-LTA samples confirms that the reduction in charged defects (Si–O^–) is due to the higher incorporation of F^– within the double four-membered ring (D4R) present in the LTA samples. We show that the accelerated crystallization is due to the role of F^– in enhancing the silica mineralization rate (formation of silicon hexafluoride species) and stabilizing D4Rs under basic conditions. Combining basic and fluoride-mediated synthesis could therefore be advantageous for faster zeolite production and improved control over structural properties for a wide variety of zeolite structures.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1821–1832 1821–1832"},"PeriodicalIF":3.2,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pyromellitic Acid-Based Cocrystals: A Mechanistic Study for the Origin of Semiconductivity via H-Coupled Charge Transfer","authors":"Sudip Sarkar,&nbsp;Suranjan Shil,&nbsp;Gobinda Chandra De* and Sushobhan Ghosh*,&nbsp;","doi":"10.1021/acs.cgd.4c0156510.1021/acs.cgd.4c01565","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01565https://doi.org/10.1021/acs.cgd.4c01565","url":null,"abstract":"<p >Organic cocrystals consisting of pyromellitic acid-4-nitro phenylenediamine (<b>1</b>) and pyromellitic acid-ethylene diamine (<b>2</b>) are reported. Cocrystals <b>1</b> and <b>2</b> were fully characterized by single-crystal X-ray diffraction, NMR, and IR spectroscopies. Conductivity measurements indicated that cocrystals <b>1</b>–<b>2</b> had semiconducting behavior in the voltage range studied (−10 to +10 V). To investigate the origin of semiconductivity, the newly synthesized cocrystals <b>1</b>–<b>2</b> and our previous pyromellitic acid-orthophenylenediamine cocrystal (<b>3</b>) were analyzed for temperature-dependent Raman spectroscopy and EPR spectroscopy. The variable-temperature Raman spectra showed altering intensity of the spectra as a function of temperature as evidence of proton transfer, whereas the EPR spectra showed a signal corresponding to single electron transfer in all three cocrystals <b>1</b>–<b>3</b>. DFT calculations performed with the crystal structures of <b>1</b>–<b>3</b> with transferred protons from the pyromellitic acid to the respective amines as well as the optimized structures with original untransformed states showed a consistent decrease of the HOMO–LUMO gap in favor of the crystal structures for all three cocrystals. Development of ground (NH₃⁺···^–OOC) and excited electronic states (NH₂···HOOC) based on the proton transfer coordinate along the N··H··O hydrogen bonding results in the spectral red shift in favor of crystal geometry, which is observed via TDDFT calculations for cocrystals <b>1</b>–<b>3</b>. The theoretical calculation of the band gap and hopping rate further supported the formation of closely spaced ground and excited electronic states to be the origin of semiconductivity for all three cocrystals <b>1</b>–<b>3</b>.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1785–1798 1785–1798"},"PeriodicalIF":3.2,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pregabalin Cocrystals with Carboxylic Acid: Structural and Thermal Analyses","authors":"Pablo E. Gaztañaga*,&nbsp;Eleonora Freire Espeleta and Daniel R. Vega,&nbsp;","doi":"10.1021/acs.cgd.4c0173610.1021/acs.cgd.4c01736","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01736https://doi.org/10.1021/acs.cgd.4c01736","url":null,"abstract":"<p >Cocrystals of pregabalin (PGB) with different carboxylic acids were developed, and their crystal structures were determined by single crystal X-ray diffraction. All obtained cocrystal structures were isostructural and related to the free PGB crystal structure (PGB_AN). These structural similarities result in analogous thermal behavior: upon heating, cocrystals segregate, with PGB_AN as one of the final products. Notably, cocrystals formed with octanoic acid exhibited multiple single crystal to single crystal phase transitions upon heating. Initially, the 1:1 stoichiometric sample exhibited a disproportion transition at 44 °C. As a result, the single crystal is a new cocrystal of 1:2 stoichiometry. Further heating induced segregation, ultimately yielding a PGB_AN single crystal. Similar behavior was observed in cocrystals with decanoic acid, but a different structure is observed in the 1:2 stoichiometry cocrystal.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1860–1871 1860–1871"},"PeriodicalIF":3.2,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Realization of Controllable Growth of N-Polarity GaN Films on SiC Substrates by Modulating the Nucleation of the AlN Buffer Layer","authors":"Yunfei Niu,&nbsp;Gaoqiang Deng*,&nbsp;Jiaqi Yu,&nbsp;Haotian Ma,&nbsp;Yusen Wang,&nbsp;Shixu Yang,&nbsp;Changcai Zuo,&nbsp;Jingkai Zhao,&nbsp;Yi Li,&nbsp;Haozhe Gao,&nbsp;Guoxing Li,&nbsp;Baolin Zhang and Yuantao Zhang*,&nbsp;","doi":"10.1021/acs.cgd.4c0150310.1021/acs.cgd.4c01503","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01503https://doi.org/10.1021/acs.cgd.4c01503","url":null,"abstract":"<p >Nitrogen-polarity (N-polarity) GaN films possess great potential in the preparation of high-performance high electron mobility transistors and long-wavelength light-emitting devices. Improving both the crystalline quality and surface morphology of N-polarity GaN films is crucial for the research and development of N-polarity nitride devices. In this work, we grew N-polarity GaN films on SiC substrates by metal–organic chemical vapor deposition. Meaningfully, we realize the controllable growth of N-polarity GaN films on SiC substrates by modulating the nucleation of the AlN buffer layer. The obtained N-polarity GaN films not only have a fine surface morphology but also possess a not-bad crystalline quality. Specifically, the root-mean-square roughness of the N-polarity GaN film over an area of 10 × 10 μm² is 1.68 nm, and the full width at half-maximum values of (0002) and (101̅2) planes X-ray diffraction rocking curves are 300 and 318 arcsec, respectively, corresponding to a threading dislocation density of ∼7.18 × 10⁸ cm^–2. Moreover, we propose a growth model of the N-polarity GaN film grown on the AlN buffer layer and analyze the mechanism by which the nucleation of AlN buffer layer affects the structural property of the N-polarity GaN film. This work presents a method for obtaining high-quality N-polarity GaN films on SiC substrates, which is beneficial for promoting the research and development of N-polarity nitride devices.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1768–1775 1768–1775"},"PeriodicalIF":3.2,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Valence Band Modulation Using Cationic Filled p Orbitals toward p-Type Conduction","authors":"Hiroshi Mizoguchi*,&nbsp;Satoru Matsuishi,&nbsp;Hiroyo Segawa,&nbsp;Noriko Saito and Hideo Hosono*,&nbsp;","doi":"10.1021/acs.cgd.5c0001210.1021/acs.cgd.5c00012","DOIUrl":"https://doi.org/10.1021/acs.cgd.5c00012https://doi.org/10.1021/acs.cgd.5c00012","url":null,"abstract":"<p >p-Type conduction is difficult in wide-gap compound semiconductors, such as transparent oxides. Anionic p orbitals primarily constituting the valence band maximum (VBM) are localized owing to their highly electronegative nature, which gives rise to a large ionization potential (Ip), leading to a difficulty in hole doping into the VBM. Here, we report a new approach to VBM modulation through the covalent interaction with filled cationic p orbitals. LaN is taken as an example. Pushing the anionic valence band (VB) to VBM by σ interaction in N–La chains between the N 2p VB and the filled La p orbitals decreases Ip and enhances the dispersion of VBM, leading to a direct-type band gap. Cationic p states (La 5p⁶) located energetically near the VB and linear coordination of La–N chains present in rock-salt-type crystal structures are keys to making the N p–La p covalent interaction strong.</p><p >We report a new approach to valence band maximum (VBM) modulation in wide-gap compound semiconductors such as transparent oxides through the covalent interaction with filled cationic p orbitals. LaN is taken as an example. Pushing the anionic valence band (VB) to VBM by σ interaction in N−La linear chains between the N 2p VB and the filled La p orbitals decreases ionization potential and enhances the dispersion of VBM, leading to a direct-type band gap.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1892–1896 1892–1896"},"PeriodicalIF":3.2,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acs.cgd.5c00012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multistimuli Responsive Behaviors of Salicylaldehyde Hydrazone Zn(II) Complexes in Solution, Solid State, and PMMA Film","authors":"Han-Wen Zheng,&nbsp;Min Wu,&nbsp;Su-Jia Liu,&nbsp;Yu-Hui Fang,&nbsp;Xue-Bin Deng* and Xiang-Jun Zheng*,&nbsp;","doi":"10.1021/acs.cgd.4c0167210.1021/acs.cgd.4c01672","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01672https://doi.org/10.1021/acs.cgd.4c01672","url":null,"abstract":"<p >Zn(II) complexes based on salicylaldehyde hydrazone ligands have emerged as a promising class of stimuli-responsive luminescent materials. Herein, three Zn(II) complexes, namely, [Zn₂(HL¹)₂(py)₂]·H₂O (<b>1a</b>), Zn₂(HL¹)₂(py)₂ (<b>1b</b>), and Zn₂(HL²)₂(py)₂ (<b>2</b>), were synthesized by self-assembly with Zn(II) and salicylaldehyde hydrazone under solvothermal conditions. Complexes <b>1a</b> and <b>2</b> exhibit reversible mechanochromic luminescence (MCL) during grinding and fuming processes due to the transformation between the crystalline phase and amorphous phase. In addition, slight grinding induces a crystal phase transformation from <b>1a</b> to <b>1b</b>. Comprehensive structural analysis and experimental results indicate that grinding may destroy the coordination bond, leading to the dissociation of the pyridine molecule from the metal center. Besides, the existence of weak interaction between molecules is easy to destroy upon external mechanical force, resulting in MCL with a high contrast. Moreover, DMSO solutions of complexes <b>1a</b> and <b>2</b> both turn from yellow to colorless accompanied by luminescence quenching after irradiating with white light. <b>1a</b> shows reversible photochromism between the switching of white light and 365 nm UV illumination with a short response time, while <b>2</b> shows a prolonged and irreversible response, potentially attributed to the steric hindrance effects. However, complex <b>2</b> exhibits a more obvious photochromic property in the solid state than complex <b>1a</b>. Its color changes from yellow to brown upon irradiation with 365 nm UV light, attributed to the formation of radicals generated by photoinduced electron transfer from the hydroxyl oxygen atom to the coordinating pyridine molecule. The PMMA film of complex <b>2</b> also exhibits a stimuli response under the irradiation of UV or white light. These salicylaldehyde hydrazone Zn(II) complexes, exhibiting MCL and photochromic properties, demonstrate significant potential as advanced multistimuli responsive materials for various applications.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1842–1850 1842–1850"},"PeriodicalIF":3.2,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Binuclear Pt(II) Complexes with N̂ĈN Ligands: Synthesis, Photophysical Properties, and Vapochromic Responses","authors":"Aiwen Yu,&nbsp;Wenkang Jiang,&nbsp;Yunjun Shen and Yuzhen Zhang*,&nbsp;","doi":"10.1021/acs.cgd.4c0174710.1021/acs.cgd.4c01747","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01747https://doi.org/10.1021/acs.cgd.4c01747","url":null,"abstract":"<p >This article presents the synthesis of four dinuclear Pt(II) complexes, <b>1a, 1b, 2a,</b> and <b>2b</b>, utilizing PtLn-Cl as the starting materials, where Ln represents an N̂ĈN coordinating ligand. The ligand L1 features a 1,3-disubstituted phenyl ring and two nitrogen heterocycles, whereas L2 replaces the nitrogen heterocycles with isoquinoline. Auxiliary ligands A1 (<i>N</i>,<i>N</i>′-diphenylformamidine) and A2 (9<i>H</i>-pyrido[2,3-<i>b</i>]indole) contribute to the formation of these complexes, which exhibit red phosphorescence. Characterization of all four complexes was conducted by using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), and single-crystal X-ray diffraction (SCXRD). The crystallographic data reveal intricate bilayer structures with Pt–Pt distances of 3.055 Å, 3.054 Å, 2.988 Å, and 3.150 Å for complexes <b>1a′</b>, <b>1b</b>, <b>2a′</b>, and <b>2b</b>, respectively. Complexes <b>2a</b> and <b>2b</b> showcase near-infrared (near-IR) emission across solid, liquid, and PMMA film states. Notably, complex <b>1a</b> exhibits the highest photoluminescence quantum yield (PLQY) of 73.2% and an emission lifetime of 3.1 μs when doped into a 1 wt % PMMA film. Due to its favorable photophysical properties, complex <b>1a</b> was applied to quartz plates for the detection of organic solvent vapors, demonstrating distinct emission quenching in response to formic and acetic acid vapors.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1872–1879 1872–1879"},"PeriodicalIF":3.2,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"N–H···N Hydrogen-Bonded Helices to Halogen···Halogen and Cation···π Interactions in Aprotic, Monoprotic, and Biprotic Halogen-Substituted Lophines","authors":"Debasis Pal,&nbsp;Subhajit Saha and Kumar Biradha*,&nbsp;","doi":"10.1021/acs.cgd.4c0174210.1021/acs.cgd.4c01742","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01742https://doi.org/10.1021/acs.cgd.4c01742","url":null,"abstract":"<p >2,4,5-triphenyl-1H-imidazole (TPI), also known as lophine, has been widely studied for its luminescence properties. With both hydrogen bond donor (N–H) and acceptor (N) sites, lophine molecules self-assemble to form 1D helices via N–H···N hydrogen bonding. Herein, crystal engineering studies of halogen-substituted 2,4,5-triphenyl-1H-imidazole (TPI) derivatives are explored to understand their supramolecular self-assembly and photophysical properties. Three classes of TPI derivatives are synthesized and studied: monoprotic (<b>1</b>–<b>4</b>), <i>N</i>-methylated aprotic (<b>1M</b>–<b>3M</b>), and biprotic salts with nitrate anions (<b>1H</b>–<b>3H</b>). Monoprotic derivatives form helices through N–H···N hydrogen bonding, while aprotic derivatives exhibit corrugated layers stabilized by halogen···π and halogen···halogen interactions. Biprotic salts form cation···π stacks that assemble into two-dimensional layers via hydrogen bonding with nitrate ions. Notably, compounds within and across classes demonstrate isostructural features and distinct intermolecular interactions that are influenced by halogen substitutions. Photophysical studies reveal absorption bands in the 243–352 nm range in solid state and 292–313 nm in solution, with fluorescence emissions spanning 377–416 and 450–470 nm upon excitation at 300 and 340 nm, respectively. These findings highlight the role of noncovalent interactions in directing crystal packing and their impact on the photophysical properties of TPI derivatives.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":"25 6","pages":"1880–1891 1880–1891"},"PeriodicalIF":3.2,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143641652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}