Crystal Growth & Design最新文献

{"title":"Impact of Isomerization of Diphenothiazine Derivatives on Photophysical Properties, Crystal Structure, and Force-Stimulus Response","authors":"He Zhao, Xiuguang Wang, Siwen Hu, Meng Liang, Pengchong Xue","doi":"10.1021/acs.cgd.4c00687","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00687","url":null,"abstract":"Two D-A-D diphenothiazine derivatives, 24DPTCN and 26DPTCN, were prepared to investigate the impact of molecular isomerization on the luminescent behaviors in solution and crystalline states and the response to the external force stimuli. It was found that the two compounds had two emission bands in solutions. The quantum chemical calculations suggest that the coexistence of two configurations results in two emission bands, the short-wavelength bands are from the axial–equatorial (<i>ax-eq</i>) form for 24DPTCN and 26DPTCN, and the long-wavelength emission bands are ascribed to those molecules in equatorial–equatorial (<i>eq-eq</i>) form. In the crystalline phase, 24DPTCN adopts an <i>ax-eq</i> form and emits very weak blue fluorescence, and 26DPTCN has an <i>eq-eq</i> conformation and emits green fluorescence. More importantly, they also possess distinct response to force stimulus. 24DPTCN had a large redshift of 85 nm in the emission band under mild force stimulus, accompanied by an enhancement in the emission intensity because of the configuration conversion from <i>ax-eq</i> to <i>eq-eq</i>. On the other hand, only a shift of 28 nm was observed, and the fluorescence weakened after 26DPTCN crystals were ground because a small number of <i>eq-eq</i> 26DPTCN transferred into <i>ax-eq</i> ones.","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194586","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":"Ag(I)···π-Influenced, Anion-Controlled Structural Variation in Coordination Networks of E-3-Pyridylvinyl Benzoxazole: Sunlight-Driven Regioselective Photodimerization in the Solid State","authors":"Shyamvarnan Baskar,&nbsp; and ,&nbsp;Goutam Kumar Kole*,&nbsp;","doi":"10.1021/acs.cgd.4c0108010.1021/acs.cgd.4c01080","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01080https://doi.org/10.1021/acs.cgd.4c01080","url":null,"abstract":"<p >The coordination chemistry of the flexible <i>N</i>-donor ligand <i>E</i>-3-pyridylvinyl benzoxazole (<b>3-PVBO</b>) with various silver salts has been investigated for the first time. Four novel coordination compounds of silver(I), namely, {[Ag₂(<b>3-PVBO</b>)](BF₄)} (<b>1</b>), {[Ag(<b>3-PVBO</b>)](CF₃SO₃)}_∞¹ (<b>2</b>), {[Ag(<b>3-PVBO</b>)(CF₃CO₂)]}_∞¹ (<b>3</b>), and {[Ag₂(<b>3-PVBO</b>)](SbF₆)}_∞¹ (<b>4</b>), have been synthesized and structurally characterized. <b>3-PVBO</b> adopts two different configurations, i.e., <i>syn</i>- and <i>anti-</i>, and offers structural variation in the series with different anions. In both <b>1</b> and <b>2</b>, it adopts <i>syn-</i>configuration, and thus, 16-membered metallacycles are formed. In <b>3</b>, with the trifluoroacetate anion, it adopts <i>anti</i>-configuration, and thus, a zigzag 1D coordination polymeric network is formed. However, in <b>4</b> with the SbF₆^– anion, despite it adopting the <i>syn-</i>configuration, instead of a metallacycle, a 1D coordination polymeric network is observed. More interestingly, <b>3-PVBO</b> ligands were found to stack parallel in <b>3</b> and <b>4</b>, suitable for the photodimerization reaction in the solid state. <b>3</b> exhibited photodimerization in the <i>head-to-tail</i> fashion, leading to the formation of the coordination polymer, {[Ag(<i>rctt</i>-HT-<b>PBOCB</b>)(CF₃CO₂)]}_∞² (<b>5</b>), where <b>PBOCB</b> = 1,3-bis(benzoxazole)-2,4-bis(3′-pyridyl) cyclobutane. However, <b>4</b> underwent photodimerization in the <i>head-to-head</i> fashion. Thus, varying the anions achieved a regioselective synthesis of functional cyclobutane derivatives. No argentophilic but Ag(I)···π interaction was observed in this series.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142237334","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":"Why Hexanitrobenzene (HNB) Molecules Are Parallelly Stacked along Their Benzene Ring Planes","authors":"Shitai Guo,&nbsp;Kairui Xue,&nbsp;Chunjie Zuo,&nbsp;Weihua Zhu and Chaoyang Zhang*,&nbsp;","doi":"10.1021/acs.cgd.4c0102610.1021/acs.cgd.4c01026","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01026https://doi.org/10.1021/acs.cgd.4c01026","url":null,"abstract":"<p >Understanding the molecular structure-crystal packing structure relationship is one of the core objectives of crystal engineering. Hexanitrobenzene (HNB) is a sensitive high-energy compound and presents a surprising molecular stacking structure, i.e., the parallel stacking along their benzene ring planes in crystal seems counterintuitive. HNB molecules each contain six NO₂ and a central frame of benzene ring surrounded by the NO₂ and feature a same sign-charged molecular edge. Given the electrostatic repulsion among the NO₂ groups of adjacent HNB molecules in the crystal, it can hardly make the parallel molecular stacking, as observed experimentally. In the present work, we confirm that the twist of NO₂ and the exposure of the molecular frame around the molecular edge are responsible for the aforementioned stacking pattern. Thereon, six negative and six positive electrostatic potential (ESP) regions alternately occur, belonging to the NO₂ and exposed molecular frame, respectively. It satisfies a necessary requirement of intralayer molecular arrangement, i.e., the alternate distribution of negative and positive ESP regions on the molecular edge. Meanwhile, the n−π interaction of the NO₂·benzene ring governs the interlayer intermolecular interactions. This work is expected to enrich the insight into molecular structure-crystal packing structure relationships.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142237306","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":"Ag(I)···π-Influenced, Anion-Controlled Structural Variation in Coordination Networks of E-3-Pyridylvinyl Benzoxazole: Sunlight-Driven Regioselective Photodimerization in the Solid State","authors":"Shyamvarnan Baskar, Goutam Kumar Kole","doi":"10.1021/acs.cgd.4c01080","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01080","url":null,"abstract":"The coordination chemistry of the flexible <i>N</i>-donor ligand <i>E</i>-3-pyridylvinyl benzoxazole (<b>3-PVBO</b>) with various silver salts has been investigated for the first time. Four novel coordination compounds of silver(I), namely, {[Ag₂(<b>3-PVBO</b>)](BF₄)} (<b>1</b>), {[Ag(<b>3-PVBO</b>)](CF₃SO₃)}_∞¹ (<b>2</b>), {[Ag(<b>3-PVBO</b>)(CF₃CO₂)]}_∞¹ (<b>3</b>), and {[Ag₂(<b>3-PVBO</b>)](SbF₆)}_∞¹ (<b>4</b>), have been synthesized and structurally characterized. <b>3-PVBO</b> adopts two different configurations, i.e., <i>syn</i>- and <i>anti-</i>, and offers structural variation in the series with different anions. In both <b>1</b> and <b>2</b>, it adopts <i>syn-</i>configuration, and thus, 16-membered metallacycles are formed. In <b>3</b>, with the trifluoroacetate anion, it adopts <i>anti</i>-configuration, and thus, a zigzag 1D coordination polymeric network is formed. However, in <b>4</b> with the SbF₆^– anion, despite it adopting the <i>syn-</i>configuration, instead of a metallacycle, a 1D coordination polymeric network is observed. More interestingly, <b>3-PVBO</b> ligands were found to stack parallel in <b>3</b> and <b>4</b>, suitable for the photodimerization reaction in the solid state. <b>3</b> exhibited photodimerization in the <i>head-to-tail</i> fashion, leading to the formation of the coordination polymer, {[Ag(<i>rctt</i>-HT-<b>PBOCB</b>)(CF₃CO₂)]}_∞² (<b>5</b>), where <b>PBOCB</b> = 1,3-bis(benzoxazole)-2,4-bis(3′-pyridyl) cyclobutane. However, <b>4</b> underwent photodimerization in the <i>head-to-head</i> fashion. Thus, varying the anions achieved a regioselective synthesis of functional cyclobutane derivatives. No argentophilic but Ag(I)···π interaction was observed in this series.","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194590","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":"Lattice Polarity Manipulation of AlN Films on SiC Substrates for N-Polar GaN HEMTs","authors":"Yunfei Niu,&nbsp;Gaoqiang Deng*,&nbsp;Tao Wang,&nbsp;Haotian Ma,&nbsp;Shixu Yang,&nbsp;Jiaqi Yu,&nbsp;Lidong Zhang,&nbsp;Yusen Wang,&nbsp;Changcai Zuo,&nbsp;Bin Duan,&nbsp;Baolin Zhang,&nbsp;Guoxing Li,&nbsp;Xiaojuan Sun,&nbsp;Dabing Li and Yuantao Zhang*,&nbsp;","doi":"10.1021/acs.cgd.4c0058510.1021/acs.cgd.4c00585","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00585https://doi.org/10.1021/acs.cgd.4c00585","url":null,"abstract":"<p >Realization of nitrogen-polar (N-polar) AlN on SiC is important for the development of high-performance GaN high-electron mobility transistors (HEMTs). However, AlN films grown on SiC substrates are mostly metal-polar, and it is difficult to achieve an N-polar AlN on them. In this work, we manipulated the lattice polarity of AlN grown on SiC by varying the V/III ratio. Our results show that AlN films grown at a low V/III ratio undergo lattice polarity reversal from N-polarity to metal-polarity near the AlN/SiC interface. This occurs because oxygen enrichment occurs in AlN, forming a thin AlON layer close to the interface. Importantly, we suppress the oxygen enrichment and thus the formation of AlON in AlN under a high V/III ratio, i.e., an N-rich growth condition, and finally achieve an N-polar AlN film on SiC. We also find that the threshold V/III ratio that realizes N-polar AlN on SiC without lattice polarity reversal is ∼6000. Furthermore, we prepared a GaN/AlGaN HEMT structure based on the obtained N-polar AlN, and the 2-dimensional electron gas density and mobility at the heterostructure interface are 1.5 × 10¹³ cm^–2 and 923 cm²/V·s, respectively. This work is expected to promote the development of N-polar GaN HEMTs on SiC.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142237336","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":"Why Hexanitrobenzene (HNB) Molecules Are Parallelly Stacked along Their Benzene Ring Planes","authors":"Shitai Guo, Kairui Xue, Chunjie Zuo, Weihua Zhu, Chaoyang Zhang","doi":"10.1021/acs.cgd.4c01026","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c01026","url":null,"abstract":"Understanding the molecular structure-crystal packing structure relationship is one of the core objectives of crystal engineering. Hexanitrobenzene (HNB) is a sensitive high-energy compound and presents a surprising molecular stacking structure, i.e., the parallel stacking along their benzene ring planes in crystal seems counterintuitive. HNB molecules each contain six NO₂ and a central frame of benzene ring surrounded by the NO₂ and feature a same sign-charged molecular edge. Given the electrostatic repulsion among the NO₂ groups of adjacent HNB molecules in the crystal, it can hardly make the parallel molecular stacking, as observed experimentally. In the present work, we confirm that the twist of NO₂ and the exposure of the molecular frame around the molecular edge are responsible for the aforementioned stacking pattern. Thereon, six negative and six positive electrostatic potential (ESP) regions alternately occur, belonging to the NO₂ and exposed molecular frame, respectively. It satisfies a necessary requirement of intralayer molecular arrangement, i.e., the alternate distribution of negative and positive ESP regions on the molecular edge. Meanwhile, the n−π interaction of the NO₂·benzene ring governs the interlayer intermolecular interactions. This work is expected to enrich the insight into molecular structure-crystal packing structure relationships.","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194588","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":"Lattice Polarity Manipulation of AlN Films on SiC Substrates for N-Polar GaN HEMTs","authors":"Yunfei Niu, Gaoqiang Deng, Tao Wang, Haotian Ma, Shixu Yang, Jiaqi Yu, Lidong Zhang, Yusen Wang, Changcai Zuo, Bin Duan, Baolin Zhang, Guoxing Li, Xiaojuan Sun, Dabing Li, Yuantao Zhang","doi":"10.1021/acs.cgd.4c00585","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00585","url":null,"abstract":"Realization of nitrogen-polar (N-polar) AlN on SiC is important for the development of high-performance GaN high-electron mobility transistors (HEMTs). However, AlN films grown on SiC substrates are mostly metal-polar, and it is difficult to achieve an N-polar AlN on them. In this work, we manipulated the lattice polarity of AlN grown on SiC by varying the V/III ratio. Our results show that AlN films grown at a low V/III ratio undergo lattice polarity reversal from N-polarity to metal-polarity near the AlN/SiC interface. This occurs because oxygen enrichment occurs in AlN, forming a thin AlON layer close to the interface. Importantly, we suppress the oxygen enrichment and thus the formation of AlON in AlN under a high V/III ratio, i.e., an N-rich growth condition, and finally achieve an N-polar AlN film on SiC. We also find that the threshold V/III ratio that realizes N-polar AlN on SiC without lattice polarity reversal is ∼6000. Furthermore, we prepared a GaN/AlGaN HEMT structure based on the obtained N-polar AlN, and the 2-dimensional electron gas density and mobility at the heterostructure interface are 1.5 × 10¹³ cm^–2 and 923 cm²/V·s, respectively. This work is expected to promote the development of N-polar GaN HEMTs on SiC.","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194589","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":"Isothiocyanate Sulfur Atom as an Acceptor Site for Halogen-Bonded Cocrystallization of Werner Ni(II) Coordination Compounds and Perfluorinated Iodobenzenes","authors":"Lidija Posavec, Dominik Cinčić","doi":"10.1021/acs.cgd.4c00697","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00697","url":null,"abstract":"We explore the halogen bond acceptor potential of the isothiocyanate sulfur atom in the synthesis of cocrystals involving metal–organic building blocks by using Werner Ni(II) coordination compounds whose pendant isothiocyanate group enables halogen bonding. A series of 14 cocrystals involving octahedral Ni(L)₄(NCS)₂ coordination compounds (L = pyridine or 4-methylpyridine) has been prepared by both crystallization from solution and liquid-assisted grinding. The effectiveness of this strategy is demonstrated by the assembly of a large family of cocrystals involving five perfluorinated iodobenzenes. For both coordination compounds, we generally obtained one cocrystal with each donor; in one case, we obtained an additional two stoichiomorphs, and in another, we obtained three additional solvates. Single-crystal X-ray diffraction experiments revealed that building units in all cocrystals are connected via S···I halogen bonds involving the donor iodine atom and the isothiocyanate sulfur atom, which is an acceptor of two and, in some cases, even three halogen bonds. Consequently, both coordination compounds act as multitopic acceptors that can form multiple halogen bonds leading to the formation of one-, two-, and three-dimensional halogen-bonded architectures. The relative shortenings of S···I distances are from 7 to 15%, while the S···I–C angles are in the range from 160 to 180°.","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142194593","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":"Effect of Alkyl Substituents on Molecular Packing and Luminescence Properties of Crystalline Thioxanthone Derivatives","authors":"Yating Wen,&nbsp;Shuaiqiang Zhao,&nbsp;Zhongzhao Yang,&nbsp;Zhiqiang Yang,&nbsp;Fan Zhang,&nbsp;Yuxiang Dai,&nbsp;Shitong Zhang,&nbsp;Haichao Liu* and Bing Yang*,&nbsp;","doi":"10.1021/acs.cgd.4c0002410.1021/acs.cgd.4c00024","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00024https://doi.org/10.1021/acs.cgd.4c00024","url":null,"abstract":"<p >Thioxanthone (TX) and its derivatives as important triplet sensitizers and photoinitiators have attracted a great deal of interest in photochemical studies; however, their luminescence properties receive less attention, which limits the understanding of the correlation between their structures and properties. Here, a series of alkyl chains (methyl (Me), ethyl (Et), propyl (<i>n</i>-Pr), and isopropyl (<i>i</i>-Pr)) are introduced on the 2-position and 4-position of TX to mainly investigate the correlation between the packing structure and the luminescence property of the resulting crystals. The alkyl substituents are found to have a negligible effect on the photophysical properties of <b>TX-2-alkyl</b> and <b>TX-4-alkyl</b> compounds in their dispersed states; however, single-crystal X-ray diffraction analysis and photophysical measurement demonstrate that the <b>TX-2-alkyl</b> and <b>TX-4-alkyl</b> crystals present distinctive packing motifs, leading to different luminescence properties. The <b>TX-2-Me</b>, <b>TX-4-Me</b>, <b>TX-4-</b><i><b>n</b></i><b>-Pr</b>, and <b>TX-4-</b><i><b>i</b></i><b>-Pr</b> crystals show a dimeric π–π packing motif; the <b>TX-2-</b><i><b>n</b></i><b>-Pr</b> and <b>TX-4-Et</b> crystals exhibit a long-range π–π monomer packing motif and the <b>TX-2-Et</b> and <b>TX-2-</b><i><b>i</b></i><b>-Pr</b> crystals display a herringbone packing motif. It is found that a change in molecular packing motif from dimeric π–π packing and monomeric π–π packing to herringbone packing generally corresponds to a gradually blue-shifted fluorescence and room-temperature phosphorescence (RTP) emission wavelengths. This work will provide a comprehensive understanding of the effect of the alkyl substituents on the packing structures and luminescence properties of the TX luminophore.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142237523","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":"Mechanisms of Three-Dimensional Solid-Phase Epitaxial Crystallization of Strontium Titanate","authors":"Tesia D. Janicki,&nbsp;Rui Liu,&nbsp;Soohyun Im,&nbsp;Zhongyi Wan,&nbsp;Serkan Butun,&nbsp;Shaoning Lu,&nbsp;Nasir Basit,&nbsp;Paul M. Voyles,&nbsp;Paul G. Evans and J. R. Schmidt*,&nbsp;","doi":"10.1021/acs.cgd.4c0008110.1021/acs.cgd.4c00081","DOIUrl":"https://doi.org/10.1021/acs.cgd.4c00081https://doi.org/10.1021/acs.cgd.4c00081","url":null,"abstract":"<p >Strontium titanate (SrTiO₃, STO) is a complex metal oxide with a cubic perovskite crystal structure. Due to its easily described and understood crystal structure in the cubic phase, STO is an ideal model system for exploring the mechanistic details of solid-phase epitaxy (SPE) in complex oxides. SPE is a crystallization approach that aims to guide crystal growth at low homologous temperatures to achieve targeted microstructures. Beyond planar thin films, SPE can also exploit the addition of a chemically inert, noncrystallizing, amorphous obstacle in the path of crystallization to generate complex three-dimensional structures. The introduction of this mask fundamentally alters the SPE process, inducing a transition from two- to three-dimensional geometries and from vertical to lateral crystal growth under the influence of the crystal/mask/amorphous boundary. Using a combination of molecular dynamics simulations and experiments, we identify several unique phenomena in the nanoscale growth behaviors in both conventional (unmasked) and masked SPE. Examining conventional SPE of STO, we find that crystallization at the interface is strongly correlated to, and potentially driven by, density fluctuations in the region of the amorphous STO near the crystalline/amorphous interface with a strong facet dependence. In the masked case, we find that the crystalline growth front becomes nonplanar near contact with the mask. We also observe a minimum vertical growth requirement prior to lateral crystallization. Both phenomena depend on the relative bulk and interfacial free energies of the three-phase (crystal/mask/amorphous) system.</p>","PeriodicalId":34,"journal":{"name":"Crystal Growth & Design","volume":null,"pages":null},"PeriodicalIF":3.2,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142237456","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}