Fluorescence mutation and structural evolution of a π-conjugated molecular crystal during phase transition

Two thermodynamically stable crystalline phases (B- and G-phases) were found for a twistable π-conjugated molecule, CN-DSB, condensed from its solution.

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Elastic behavior, phase transition, and pressure induced structural evolution of analcime

American Mineralogist ◽

10.2138/am.2006.1994 ◽

2006 ◽

Vol 91 (4) ◽

pp. 568-578 ◽

Cited By ~ 37

Author(s):

G. D. Gatta ◽

F. Nestola ◽

T. B. Ballaran

Keyword(s):

Phase Transition ◽

Structural Evolution ◽

Elastic Behavior

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Unraveling microstrain-promoted structural evolution and thermally driven phase transition in c−Sc2O3 nanocrystals at high pressure

Physical Review B ◽

10.1103/physrevb.102.214115 ◽

2020 ◽

Vol 102 (21) ◽

Author(s):

Yongtao Zou ◽

Mu Li ◽

Wei Zhang ◽

Cangtao Zhou ◽

Tony Yu ◽

...

Keyword(s):

Phase Transition ◽

High Pressure ◽

Structural Evolution ◽

Thermally Driven

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Effect of Annealing Temperature on Phase Transition of Nanoalumina Synthesized by Auto-Combustion Route

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.41.74 ◽

2016 ◽

Vol 41 ◽

pp. 74-86 ◽

Cited By ~ 3

Author(s):

Muhammad Adil ◽

Hasnah Mohd Zaid ◽

Kean Chuan Lee ◽

Noor Rasyada Ahmad Latiff

Keyword(s):

Phase Transition ◽

Particle Size ◽

Sol Gel ◽

Thermo Gravimetric Analysis ◽

Amorphous State ◽

Specific Area ◽

Combustion Method ◽

Gravimetric Analysis ◽

Crystalline Phases ◽

Auto Combustion

Nanocrystalline Al2O3 powder has been successfully synthesized by a simple and fast sol-gel auto-combustion method. The transformation of crystalline phases of as-synthesized nano powders was investigated through X-ray diffraction in terms of their crystallinity and crystallite size. Subsequently, a detailed transmission electron microscopy (TEM) investigation, including specific area electron diffraction (SAED) analysis revealed the crystallographic alterations and morphological information even at lattice scale which co-include the XRD analysis. The results obtained allow to explain the evolution of an amorphous state into different crystalline phases with increased calcining temperature; and their relation to particle size. The particle size is found to be closely related to phase transition of Al2O3 from γ → δ → θ → κ →α. The existence of distinctive bonds and band energy were studied by employing Fourier-transform infrared spectroscopy (FTIR) and UV-visible spectroscopy, respectively. On the other hand, thermo gravimetric analysis (TGA) had also been performed to confirm the phase purity of nano powder.

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Infrared bands to distinguish amorphous, meso and crystalline phases of poly(lactide)s: Crystallization and phase transition pathways of amorphous, meso and co-crystal phases of poly(ʟ-lactide) in the heating process

Polymer ◽

10.1016/j.polymer.2021.124495 ◽

2021 ◽

pp. 124495

Author(s):

N.M. Praveena ◽

P. Shaiju ◽

R.B.Amal Raj ◽

E. Bhoje Gowd

Keyword(s):

Phase Transition ◽

Heating Process ◽

Crystalline Phases ◽

Transition Pathways ◽

Crystal Phases

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Drastic photoluminescence modulation of an organic molecular crystal with high pressure

Materials Chemistry Frontiers ◽

10.1039/c9qm00082h ◽

2019 ◽

Vol 3 (8) ◽

pp. 1510-1517 ◽

Cited By ~ 7

Author(s):

Junjie Guan ◽

Chunfang Zhang ◽

Dexiang Gao ◽

Xingyu Tang ◽

Xiao Dong ◽

...

Keyword(s):

Phase Transition ◽

High Pressure ◽

Molecular Crystal ◽

Near Infrared ◽

Infrared Region ◽

Photoluminescence Spectra ◽

Organic Molecular Crystal ◽

Greenish Yellow ◽

Near Infrared Region

The pressure-induced phase transition of diphenylfluorenone leads to a drastic redshift of the photoluminescence spectra from greenish-yellow to the near-infrared region.

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High-temperature structural evolution of hexagonal multiferroic YMnO3and YbMnO3

Journal of Applied Crystallography ◽

10.1107/s0021889807025101 ◽

2007 ◽

Vol 40 (4) ◽

pp. 730-734 ◽

Cited By ~ 40

Author(s):

Il-Kyoung Jeong ◽

N. Hur ◽

Th. Proffen

Keyword(s):

Phase Transition ◽

High Temperature ◽

Powder Diffraction ◽

Structural Parameters ◽

Structural Evolution ◽

Neutron Powder Diffraction ◽

Temperature Behaviour ◽

Rietveld Refinements ◽

Polar Structure ◽

Diffraction Patterns

Neutron powder diffraction studies on the structural evolution of hexagonal multiferroic YMnO3and YbMnO3from 1000 K to 1400 K, and from 1000 K to 1350 K, respectively, are presented. The temperature evolution of diffraction patterns suggests that YMnO3undergoes a phase transition to a non-polar structure above 1200 K, while YbMnO3remains ferroelectric up to 1350 K. Detailed structural parameters were obtained as a function of temperature from Rietveld refinements. Based on this result, the distinct differences in temperature behaviour between YMnO3and YbMnO3, and the origin of the ferroelectricity in these hexagonal multiferroics are discussed.

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Investigation of structural phase evolution and dielectric response of Co-doped BaTiO3

Journal of Advanced Dielectrics ◽

10.1142/s2010135x18500248 ◽

2018 ◽

Vol 08 (04) ◽

pp. 1850024 ◽

Cited By ~ 6

Author(s):

Amantulla Mansuri ◽

Ilyas Noor Bhatti ◽

Imtiaz Noor Bhatti ◽

Ashutosh Mishra

Keyword(s):

Phase Transition ◽

Structural Study ◽

Structural Phase ◽

Structural Evolution ◽

Phase Evolution ◽

Dielectric Measurement ◽

Cubic Phase ◽

Tangent Loss ◽

Ionic Radii ◽

Co Doping

In the present study, we have synthesized polycrystalline samples of BaTi[Formula: see text]CoxO3 (BTCO) ([Formula: see text], 0.01, 0.03, 0.05, 0.07 and 0.10) with standard solid state reaction technique. The obtained samples are characterized by X-ray diffraction (XRD) and Raman spectroscopy for structural study. The detailed structural analysis has been performed by Rietveld refinement using Fullprof program. We observed an increase in lattice parameters, which results due to substitution of Co[Formula: see text] with large ionic radii (0.9[Formula: see text]Å) for smaller ionic radii (0.6[Formula: see text]Å) Ti[Formula: see text]. Moreover, peak at 45.5∘ shifts to 45∘ on Co doping, which is due to structure phase transition from tetragonal to cubic. Raman study infers that the intensity of characteristic peaks decreases and line width increases with Co doping. The bands linked with the tetragonal structure (305[Formula: see text]cm[Formula: see text]) decreased due to the tetragonal-to-cubic phase transition with Co doping. Our structural study reveals the expansion of BTCO unit cell and tetragonal-to-cubic phase transformation takes place. The results from different characterization techniques are conclusive and show structural evolution with Co doping. The samples are further characterized by dielectric spectroscopy, dielectric measurement reveals the increase of dielectric constant and transition [Formula: see text]C is observed for Barium titanate (BaTiO3), whereas transition disappears with Co doping. Both temperature and frequency-dependent tangent loss is also studied.

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