Crystal Structure Transformation Research Articles

Preparation, characterization, stability, and antioxidant of quercetin-loaded hyaluronic acid complexes via pH-induced co-assembly

The purpose of this study was to investigate the feasibility of constructing an oral delivery system for quercetin (QUT) using hyaluronic acid (HA) as the wall material. The findings revealed that when the mass ratio of QUT to HA was 1:10, the prepared QUT-HA complexes exhibited excellent stability (particle size of 802 nm, zeta potential of -36 mV) and QUT loading capacity (encapsulation efficiency of 79.77%, loading capacity of 89.65 mg/g). The characterization of QUT-HA complex confirmed the formation of hydrogen bond between QUT and HA, resulting in a homogeneously dispersed coral-like complex and leading to the transformation of QUT's crystal structure into an amorphous state. Environmental stability analysis demonstrated that the QUT-HA complex maintains good stability within an ionic concentration range of 0-500 mM, a pH range of 3-8, and at temperatures of 50-90°C. In vitro simulations of gastrointestinal digestion indicated that the QUT-HA complex aggregates during simulated gastric fluid digestion and dissociates following simulated intestinal fluid digestion, effectively enhancing the bioaccessibility of QUT. Antioxidant assays showed that the scavenging ability of QUT against DPPH and ABTS radicals was significantly improved by complex loading. Therefore, the QUT-HA complex developed in this study possesses a high QUT loading capacity, excellent processing and digestive stability, and can effectively enhance the bioaccessibility and antioxidant activity of QUT, making it a promising candidate for use as an oral nutritional supplement in the field of functional foods.

Deformation mechanism and microstructure evolution of newly developed Ti-42.5Al-4Nb-0.5Mo-0.1B-(C, W, Y) alloy

A novel Ti-42.5Al-0.5Mo-0.1B-0.2W-0.25C-0.05Y alloy with a nearly lamellar structure was explored to better understand the deformation behavior and microstructure evolution during hot compression test at a high strain rate of 10s-1. Cylindrical samples were compressed in the temperature range of 1373K to 1523K, with the true strain reaching 69%. The results show that the crystal structure and phase transformation have an influence on the deformation mechanisms. Regarding the Tα2→α transformation within the deformation temperature range of 1373K - 1473K, the nucleation and growth of dynamically recrystallized (DRXed) γ and α grains can alternate in dominating the hot deformation of the present alloy. When the deformation temperature is 1523K, the softening mechanism mainly is the dynamic recovery (DRV) of the α phase. Moreover, the deformation temperature also has a significant effect on phase fractions and the critical values of dynamic recrystallization. Specifically, as the temperature rises, the proportion of the α phase increases, the proportion of the γ phase decreases sharply, the content of the β phase remains stable, and the critical values of dynamic recrystallization decrease. Additionally, fine equiaxed α2 grains with an average size of 8 μm were obtained at 1523K and 10s-1, which provided a reference for obtaining a fine near-lamellar or full-lamellar microstructure in TiAl alloys.

The mechanism of the impact of Li2MnO3 with dual-edged sword functionality on the cyclic performance of lithium-rich manganese-based cathode materials

The Li2MnO3 phase is a double-edged sword hanging over lithium-rich manganese-based cathode materials (LLOs). It provides a theoretical specific capacity of over 300mAh/g for LLOs, but it is also the main source of issues such as low Initial Coulombic efficiency (ICE), poor rate performance, and voltage decay. In recent years, related research has primarily focused on the lattice oxygen. From the perspective related to the Li2MnO3 phase, this study achieves different activation degrees of Li2MnO3 phase through ingenious electrochemical methods. It conducts a detailed analysis of the phase transition and polarization of Li2MnO3 phase under high and low rates, and delves into the different mechanisms that cause the electrochemical performance degradation of LLOs under high and low rates. The results show that during low-rate cycling, the more Li2MnO3 phase in LLOs, the more transformation of crystal structure from layered to spinel phase occurs during cycling, and the structural transformation of the material will ultimately lead to the degradation of cycle performance and voltage decay. During high-rate cycling, due to the intrinsic conductivity difference of Li2MnO3 phase, the large polarization effect of LLOs can lead to severe decomposition of the electrolyte at high voltages, resulting in the degradation of cycle performance. Therefore, conducting research on LLOs focused on the Li2MnO3 phase may be an effective approach, providing a new modification idea for achieving more excellent cycling performance of LLOs.

Structural characteristics of Bi2O2CO3 nanosheets synthesized by nano-pulsed discharges in water

A comprehensive analysis of Bi2O2CO3 nanosheets, which were synthesized using nanosecond-pulsed discharges in water between bismuth electrodes, was conducted in order to investigate the crystallographic features of this material. Electron diffraction, X-ray diffraction and electron energy-loss spectrometry techniques revealed the presence of a stoichiometric tetragonal Bi2O2CO3 structure, labelled BOC in this study. It crystallizes in the body-centred tetragonal Bravais lattice and belongs to the I4/mmm space group (No. 139), with the following lattice parameters: a = 3.91, c = 13.77 Å. The nanosheets adopt square shapes. This shape is dictated by the symmetry elements of its point group (4/mmm) under the prevailing local conditions. From the energetic point of view, this shape, dictated by the 4/m2/m2/m point group and therefore a pinacoid, corresponds to an absolute extremum, an indicator of the stability of these BOC nanosheets. Most nanosheets are crossed by equal-inclination fringes or bend contours. These bend contours reflect the fact that the BOC nanosheets contain crystal defects and/or are so thin that they bend elastically, leading to rotation of the lattice planes towards the diffracting Bragg position. The diffraction patterns corresponding to bend contours intersecting along the [001] zone axis have been studied in detail. Extra reflections are superimposed on the diffraction pattern of the BOC crystallographic structure. These extra reflections are essentially attributed to two phenomena: multiple diffraction and local disorder–order transformations of the BOC crystal structure, passing from a body-centred tetragonal to a primitive Bravais lattice. A mechanism related to the ledge mechanism (kinks and jogs), explaining the formation of nanosheets in a metallic matrix, has been adapted and proposed for the formation of BOC nanosheets in water. When the nanosheets are removed from the water, they become carbonated once in the air, leading to the formation of BOC that inherits the nanosheet morphology.

Fabricating highly stable and reliable vanadium dioxide thin films: Insights from radio frequency magnetron sputtering

This study establishes an optimization protocol to fabricate a stoichiometric VO2 thin film onto the glass substrate using a single process step in RF magnetron sputtering. An interplay between the substrate temperature and the oxygen-to-argon ratio in process gas is shown to achieve a range of VOx composition (from oxygen-rich to oxygen-deficient phases). The re-sputtering phenomenon is found to be crucial at higher temperature (T ≥ 873 K), leading to a shift in stoichiometry from V2O5 to V2O3. Moreover, a process model for the fabrication of various VOx compounds in thin film form is also established in this study. The crystal structure transformation from M1 to R phase for these VO2 thin films deposited over a range of process conditions is found to be 339 ± 1 K, in close agreement with the reported value for the bulk VO2. In spite of the microstructural variations, these films are found to show consistent phase transition behavior, excellent stability, and reliability in repeated thermal cycles. These films show a semiconductor-to-metal transition, which is correlated to their structural phase transformation temperature. Moreover, this study also establishes a correlation between various external stimuli, widening the usage of this material in a range of applications.

Terahertz characterization of organic crystals using paraffin as dilution matrix

Terahertz waves exhibit excellent performance in molecular information detection of substances. Since natural materials exhibit weak absorption of terahertz waves, it's conventional to involve mixing analyte with polymer diluents and pressing them into pellets, or enhance the light-material interaction through coupling systems of natural materials with metamaterials. However, both pressure-induced metastable crystal structure transformations and spatial overlap between the analyte and metasurfaces can impact the absorption of terahertz waves by organic crystals. This paper proposes a novel analytical approach using paraffin as a dilution matrix for qualitatively and quantitatively characterizing organic crystals with THz spectroscopy. The featureless refractive index spectra and negligible absorption demonstrated the feasibility of paraffin as a diluting analyte. The analytical process was further demonstrated with well-studied lactose by being diluted in molten paraffin at different mass-ratios and solidified as pellets under room temperature and ambient pressure. A continuous wave terahertz frequency domain spectroscopy system (THz-FDS) is used for spectral acquisition over 0.4–1.3 THz. The experimental results reveal a significant linear correlation between the absorption coefficient peak areas and molar concentration of lactose, with a correlation coefficient R2 of 0.9678. Our method provides an additional optional dilution matrix for terahertz spectroscopy characterization of organic crystals, enabling non-destructive, rapid, and direct measurement of metastable crystals. Furthermore, this study on paraffin as a binder material holds potential for enhancing spatial overlap between natural materials and metamaterials in the field of metasurface-enhanced sensing.

Anatase to rutile transition in TiO2 thin films: Role of tantalum and oxygen

The present study discusses the optimal solubility limit of tantalum in anatase TiO2 thin films (dopant solubility limit) and its effect on crystal structure transformation to the rutile phase. The study also focuses on the role of lattice oxygen in this structural phase transition. The detailed chemical composition, constitution, and phase of these sputter-deposited thin films are correlated with their electrical and optical properties to understand the disparity between total impurity concentration in these films and actual impurity substitution into the host lattice sites (dopant content). Reduced oxygen vacancies from the oxygen lattice sites and/or Ta substitution in Ti lattice sites are found to hinder the anatase to rutile phase transformation in TiO2 thin films. Our experimental data indicates the solubility limit of Ta being < 5 at% in TiO2. Similar behavior is seen when Ta is replaced with Nb in TiO2 thin films. Moreover, an increased oxygen and/or impurity concentration is found to lead to impurity-rich-oxides in these films, degrading the electrical conductivity.

Ball-milling preparation of La2O3/AgI nanocomposite with enhanced photocatalytic activity

La2O3/AgI nanocomposite was prepared using ball-milling, resulting in the transformation of AgI crystal structure and the formation of heterostructure with La2O3. The nanocomposite showed enhanced photocatalytic performance in degrading antibiotics and dehydrogenating organic compounds. The influence of AgI content on the photocatalytic performance was examined, and all composites showed improved catalytic activity compared to individual La2O3 and AgI. The enhanced activity is attributed to smaller particle size, heterostructure formation, build-in electric field, effective charge carrier separation and transfer. Active species trapping experiment and EPR measurement revealed that superoxide radicals and photogenerated holes are the main active species.

The structural and digestive properties of indica rice starch-fatty acid complexes

The structural and digestive properties of indica rice starch-fatty acid complexes and the effects of lipoxygenase on the structural and digestive properties of the complexes were examined in this study. The complexes were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy and Raman spectroscopy. The results showed that indica rice starch had the highest molecular chain order and the highest crystallinity, and the crystallization disappeared after gelatinization, and the formation of indica rice starch-fatty acid complexes promoted the transformation of starch crystal structure from A-type to V-type. Lipoxygenase reduced the regularity of starch molecular crystal structure in the complexes, while enzyme protein improved the order of starch molecular structure in the complexes. The regularity of starch crystal structure in the complexes could improve with the increase of composite temperature and the increase of fatty acid unsaturation. In vitro digestibility and in vitro digestion kinetics showed that the formation of indica rice starch-fatty acid complexes reduced the digestibility of indica rice starch to a certain extent. The RDS content of indica rice starch was 66.42 ± 0.39 %, and lipoxygenase reduced the reduction of rapidly digested starch content during complexes digestion, while enzyme protein increased the content of resistant starch.

Revaling the mechanism of microscopic kinking phenomena in Hf6Ta2O17 superstructures

As a promising candidate for a new-generation thermal barrier coating material, Hf6Ta2O17 is characterized by its unique long-period superstructures and excellent mechanical properties. In this study, the unique "kinking" phenomenon of the atomic arrangement in Hf6Ta2O17 crystals is directly visualized via high-resolution transmission electron microscopy for the first time. The evolution of the microstructure, and particularly the micro-mechanism of the "kinking" phenomenon, have been further explored by first-principles calculations. The study suggests that this phenomenon is primarily triggered by the rotation of the polyhedral structure, resulting from the partial elongation or shortening of the Ta-O bond length. These structural alterations are believed to directly influence the macroscopic mechanical properties and can improve the tensile properties of the Hf6Ta2O17 crystals. The findings of this study provide an important microscopic perspective for understanding the strain-induced crystal structure transformation. The quantitative analysis of the strengths of Ta-O and Hf-O bonds in different coordination polyhedra reveals the electronic structure changes behind the crystal structure transition, thus providing a new theoretical basis for an in-depth understanding of the behavior of crystals under the external stress.

Preparation of Al2O3 thin films by RS-ALD and edge passivation application for TOPCon half solar cells

A rotary spatial atomic layer deposition (RS-ALD) method is proposed for the preparation of high-quality Al2O3 thin films and its application to the edge passivation of tunnel-oxide passivated contact (TOPCon) half solar cells. The high- quality Al2O3 thin films were prepared on silicon wafers by optimizing the process conditions with a process pressure of 4 Torr and a trimethylaluminum (TMA, (CH3)3Al) flow rate of 300 sccm. The Al2O3 thin films were annealed to analyse the transformation of the film crystal structure, surface morphology, and passivation properties. Compared to the half solar cells without edge passivation, the efficiency of the cell with only deposited Al2O3 increased by 0.098 %, and the module power increased by 3.08 W. The efficiency of the cell with deposited Al2O3 + annealing increased by a further 0.021–0.119 %, and the module power increased by a further 0.68–3.76 W.

Investigation of Microstructure, Mechanical, and Tribological Behavior of Nano‐Y2O3, TiO2, ZrO2‐Dispersed W–Ni–Nb–Mo–Zr Alloys Fabricated by Spark Plasma Sintering

W–Ni–Nb–Mo–Zr alloys with 1.0 weight% (wt%) Y2O3 (alloy A), TiO2 (alloy B), ZrO2 (alloy C) dispersion synthesized by mechanical alloying for 20 h have been subjected to spark plasma sintering at 1150 °C with 65 MPa pressure and 5 min holding time. X‐ray diffraction analysis reveals the occurrence of intermetallics (W2Zr, NiNb, Ni10Zr7, MoNi), which improves the strength of the alloys. Field‐emission scanning electron microscopy analysis shows that the grain size of alloy A is less compared to alloy B and C. Energy‐dispersive spectroscopy reveals the presence of oxides at the matrix interface. Maximum % relative sintered density, ultrahigh hardness, excellent compressive strength, % compressive strain at the maximum compressive load of 99.5%, 20.42 GPa of 2.55 GPa, 9.7%, respectively, have been recorded for alloy A. Maximum texture intensity of 1.5 is recorded for alloy A which supports the superior mechanical properties. The specific wear rate of alloy A is around 2.78 times less compared to alloy C. The crystal structure transformation of ZrO2 from monoclinic to tetragonal after sintering deteriorates the mechanical properties and wear resistance in alloy C. The article also reports the operative wear mechanism in the studied oxide dispersion‐strengthened alloy.

Disposal of spent V2O5-WO3/TiO2 catalysts: A regeneration principle based on structure-activity relationships from carrier transformations

Characterization and evaluation of hazardous spent V2O5-WO3/TiO2 catalysts are critical to determining their treatment or final disposal. This study employs a thermal approach to simulate the preparation of spent catalysts derived from commercial V2O5-WO3/TiO2 catalysts and investigate the structure-activity relationship of the carrier changes during the deactivation process. The results indicate that the catalyst carrier undergoes two processes: an increase in grain size and a transformation in crystal structure. Both structural and catalytic investigations demonstrate that the grain size for catalyst deactivation is 24.62 nm, and the formation of CaWO4 occurs before the crystalline transformation. The specific surface area is susceptible to an increase in grain size. The reactions of selective catalytic reduction involve the participation of both Brønsted acid and Lewis acid sites. The deactivation process of the carrier initially affects Brønsted acid sites, followed by a reduction in Lewis acid sites, resulting in a decline in NH3 adsorption capacity and oxidation. Correlation analysis reveals that changes in the physicochemical properties of the catalyst reduce the NO conversion, with the order being The grain size > Total acid amount > The surface area. It is recommended to recycle the spent catalyst if the carrier grain size is less than 25 nm. The findings of this investigation contribute to expanding the database for evaluating and understanding the physicochemical properties of spent catalysts for disposal.

Ca substitution effects on structure transformation and physical properties of (Eu,Ca)FeAs2 co-doped with La and Co

In this study, Ca substitution and carrier doping effect on phase formation temperature and physical/superconducting properties of (Eu0.9-xCaxLa0.1)(Fe0.97Co0.03)As2 ((Eu,Ca)112, x = 0–0.4) compounds were investigated. The best synthesis condition for obtaining pure phases vary (850–900 °C) depending on the Ca substitution amount. Ca substitution in the EuFeAs2 structure induced a structural transformation from orthorhombic I2mm to monoclinic P21/m symmetry. Single crystals of EuFeAs2 and (Eu0.9La0.1)FeAs2 were grown and their crystal structures were determined. Density functional theory calculations confirmed the transformation and stability of the La-doped Eu112 crystal structure with Ca substitution. Compared with the parent compound EuFeAs2, the effective substitution of Ca reduced the lattice constants. The magnetic and transport properties of (Eu0.9-xCaxLa0.1)(Fe0.97Co0.03)As2 compounds were studied using the temperature and field dependence of the magnetization and electrical resistivity measurements. Ca substitution suppressed the magnetic ordering of Eu and gradually reduced the Néel temperature TNEu. As determined by the magnetization and electrical resistivity data, the onset of critical temperature (Tc) values increased with Ca substitution increment from 26 K to 32.2 K and 31 K–34.8 K, respectively. Ca substitution slightly increased the upper critical field values, while the coherence length ξ values were slightly decreased. The Ca substitution and sintering temperature dependence of superconductivity, upper critical fields, lower critical fields, and Eu-related magnetic transitions were extracted. The new series of Eu-containing iron-based superconductors with high Tc provides an interesting playground in this field.

Effect of Al and Si content on properties of Ti(1-x-y)AlxSiyN coating materials: First-principles calculation

This paper investigates the effect of Al and Si atomic doping on the Ti(1-x-y)AlxSiyN alloy using density functional theory (DFT). The results indicate that the phase structure stability of the alloy decreases with increasing Al and Si doping content. Particularly, excessive doping leads to the transformation of crystal structure from rocksalt to wurtzite structure with lower mechanical properties. The bulk modulus of the alloy decreases with the increase of doping content. Specifically, Al atom doping initially reduces and then increases the shear modulus and Young's modulus of Ti1-xAlxN, while Si atom doping causes the shear modulus and Young's modulus of Ti0.375-yAl0.625SiyN to increase first and then decrease. In terms of hardness, the hardness of Ti1-xAlxN increases with the increase of Al doping, but the toughness decreases. Si atom doping further enhances the alloy's hardness, reaching a maximum of 29.8 GPa, consistent with the trends observed in experimental results. Electronic structure analysis reveals that Al and Si doping induces orbital hybridization, enhancing the bonding ability and chemical bond strength between atoms. The results confirm that the ionic bonds, metal bonds and covalent bonds in multi-component nitride jointly determine the mechanical properties of the alloy.

Effect of crystal orientation on surface/subsurface damage characteristics of nano-cutting Ni-based single crystal superalloy

In ultra-precision machining, material anisotropy has an essential impact on surface generation and subsurface damage. In this work, the molecular dynamics method is applied to create the diamond nano-cutting models of Ni-based single crystal (NBSX) superalloy workpieces with different crystal orientations, and the surface/subsurface damage characteristics, crystal structure changes, cutting force, and atomic temperature and stress are discussed. The results show significant differences in surface/subsurface quality, crystal structure transformation, cutting force, atomic temperature and stress distributions and dislocation density obtained from nano-cutting workpieces along different crystal orientations. In four groups of workpieces, the surface/subsurface quality is used as an evaluation index, which shows that the [110](001) crystal orientation has the best cutting effect, and the [111](1‾ 10) crystal orientation is the worst cutting direction. This work reveals the damage generation mechanism of the machined surface/subsurface of NBSX superalloy on an atomic scale, which provides technical support for improving machining quality and optimizing machining parameters.

Solvent and Dihalide Substituent Effects on Crystal Structure, Spin‐Crossover Behavior and Conductivity of the Cationic Mn(III) Complexes with Electroactive TCNQ Counteranions

AbstractCationic Mn(III) complexes with 3,5‐Hal‐sal2323 (Hal=diCl, diBr, BrCl) ligands containing electroactive TCNQ anions as counterions have been synthesized: [Mn(3,5‐diCl‐sal2323)](TCNQ)2 (1), [Mn(3,5‐diBr‐sal2323)]2(TCNQ)3⋅6CH3CN (2), and [Mn(3,5‐Br,Cl‐sal2323)]2(TCNQ)3⋅6CH3CN (3). The crystal structures, magnetic and conducting properties of the obtained compounds have been investigated. In 1, an incomplete spin transition from the low‐spin (LS) state at 100 K to the high‐spin (HS) state upon heating to 400 K is observed. Isostructural complexes 2 and 3 contain 6 molecules of solvated acetonitrile, which is lost upon heating, accompanied by the crystal structure transformation. As a result, desolvated complexes jump to the HS state. The temperature dependences of resistivity 2 and 3 show resistivity jumps associated with the loss of lattice solvent.

Analysis of the Dissolution Behavior of Theophylline and Its Cocrystal Using ATR-FTIR Spectroscopic Imaging.

Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopic imaging is a powerful tool to visualize the distribution of components, and it has been used to analyze drug release from tablets. In this work, ATR-FTIR spectroscopic imaging was applied for observing the dissolution of molecular crystals from tablet compacts. The IR spectra provided chemically specific information about the transformation of crystal structures during the dissolution experiments. Theophylline (TPL) anhydrate and its cocrystals were used as model systems of molecular crystals. The IR spectra during the dissolution of TPL revealed information about the crystal structure of TPL, which transformed from anhydrate to monohydrate in water. During a dissolution test of a model cocrystal system, it was suggested that an active pharmaceutical ingredient (API) and a coformer were dissolved in water simultaneously. The IR spectra that were acquired during the dissolution of a cocrystal tablet showed new spectral bands attributed to the API after 5 min. This suggested that the precipitation of API was observed during the dissolution experiment. Measurements from ATR-FTIR spectroscopic imaging can visualize the drug release from the tablet and determine the transformation of molecular crystals during their dissolution. These results will have an impact on clarifying the dissolution mechanism of molecular crystals.

Effect of stabilization and carbonization treatment on the chemical and physical transformation of polyacrylonitrile (PAN) based electrospun carbon nanofibers

The present study delves into the production of carbon nanofibers (CNFs) utilising electrospun polyacrylonitrile (PAN) nanofiber mats, with a specific focus on the influence of oxidative stabilisation and carbonisation treatments. This research aims to thoroughly understand how variations in stabilisation time and temperature, as well as carbonisation temperature, impact the CNFs properties. These properties include fiber size, morphology, chemical and crystal structure transformation, thermal behaviour, and surface characteristics. Our methodology involved a detailed examination of the thermal treatment processes, where we observed a significant decrease in fiber size, though the surface morphology of the fibers remained largely unaffected. We employed Fourier-transform infrared (FTIR) spectroscopy to track the transformation of nitrile groups in PAN to imine groups, which indicated the progression of cyclisation reactions. Complementary analyses through differential scanning calorimetry (DSC) confirmed a high degree of these reactions, particularly at stabilisation temperatures extending to 250 °C and beyond. The cyclisation process was found to be complete during the carbonisation phase, at temperatures reaching 450 °C and above. Further, x-ray diffraction (XRD) patterns offered insight into the changes in the crystal structure, particularly in the packing of the d(002) spacing because of the stabilisation and carbonisation processes. This findings from this study not only elucidate the intricate process of CNFs production from electrospun PAN nanofiber mats but also highlight the critical factors that influence their final properties. These insights are invaluable for the development of advanced CNFs with tailored properties suitable for a range of applications, including but not limited to energy storage, electronics, and as supporting materials in various technological domains.

Expanded Stability of Layered SnSe-PbSe Alloys and Evidence of Displacive Phase Transformation from Rocksalt in Heteroepitaxial Thin Films.

Bulk PbSnSe has a two-phase region, or miscibility gap, as the crystal changes from a van der Waals-bonded orthorhombic 2D layered structure in SnSe-rich compositions to the related 3D-bonded rocksalt structure in PbSe-rich compositions. This structural transition drives a large contrast in the electrical, optical, and thermal properties. We realize low temperature direct growth of epitaxial PbSnSe thin films on GaAs via molecular beam epitaxy using an in situ PbSe surface treatment and show a significantly reduced two-phase region by stabilizing the Pnma layered structure out to Pb0.45Sn0.55Se, beyond the bulk limit around Pb0.25Sn0.75Se at low temperatures. Pushing further, we directly access metastable two-phase films of layered and rocksalt grains that are nearly identical in composition around Pb0.50Sn0.50Se and entirely circumvent the miscibility gap. We present microstructural and compositional evidence for an incomplete displacive transformation from a rocksalt to layered structure in these films, which we speculate occurs during the sample cooling to room temperature after synthesis. In situ temperature-cycling experiments on a Pb0.58Sn0.42Se rocksalt film reproduce characteristic attributes of a displacive transition and show a modulation in electronic properties. We find well-defined orientation relationships between the phases formed and reveal unconventional strain relief mechanisms involved in the crystal structure transformation using transmission electron microscopy. Overall, our work adds a scalable thin film integration route to harness the dramatic contrast in material properties in PbSnSe across a potentially ultrafast crystalline-crystalline structural transition.