High-Pressure Raman Study of [2.2]Paracyclophane

Li, Wei; Sui, Zhilei; Liu, Huarong; Zhang, Zengming; Liu, Hewen

doi:10.1021/jp504390u

Cited by 11 publications

(11 citation statements)

References 41 publications

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“…An extensive literature survey shows that ball milling has been used to synthesize several ferroelectric and multiferroic materials [6][7][8][9]. However, very few reports are available on the synthesis and extensive characterization of Ba 1-x Sr x TiO 3 via ball milling.…”

Section: Introductionmentioning

confidence: 99%

Structural, dielectric and ferroelectric studies of Ba1−xSrxTiO3 ceramics prepared by mechanochemical activation technique

Jain

Panwar

Jha

2016

J Mater Sci: Mater Electron

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In the present study, specimens of composition Ba 1-x Sr x TiO 3 (x = 0.0, 0.05, 0.075, 0.10 & 0.15) were synthesized using mechanochemical activation technique and their structural, dielectric and ferroelectric characteristics were investigated for the major applications such as a multi-layered ceramic capacitor (MLCC) and microwave tunable devices. Structural analysis using X-ray diffraction pattern of the systems by Rietveld refinement confirms the formation of tetragonal phase with P4 mm space group. The intensity ratio of bonds and wave number shift in Raman spectra suggests little structural changes with strontium content. Microstructural investigation reveals that there is no appreciable change in grain size with increasing strontium concentration. The results on the variation of dielectric constant with temperature suggest the shifting of Curie temperature to lower temperature side with increasing strontium concentration. Current-voltage characteristics reveal that with increasing strontium content current increases which can be correlated with the observed variation of activation energy of the studied samples, which also decreases with the increasing concentration of strontium.

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Section: Introductionmentioning

confidence: 99%

Structural, dielectric and ferroelectric studies of Ba1−xSrxTiO3 ceramics prepared by mechanochemical activation technique

Jain

Panwar

Jha

2016

J Mater Sci: Mater Electron

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“…[2,2]-Paracyclophane and its reactivity are of great interest to the synthetic chemist as paracyclophanes and their derivatives are widely used reagents in synthetic chemistry (de Meijere & Kö nig, 1997;Elacqua & MacGillivray, 2010;Paradies, 2011;Chang et al, 2012;Elacqua et al, 2012;Vö gtle, 1990;Hopf & Gleiter, 2004;Hopf, 2012;Li et al, 2014;Meyer-Eppler et al, 2014). To obtain the most information on the structure/reactivity relationship a charge density investigation is unequivocally the most informative course of action (Stalke, 2011(Stalke, , 2012aGatti & Macchi, 2012).…”

Section: Introductionmentioning

confidence: 99%

Charge density investigations on [2,2]-paracyclophane – in data we trust

Wolf

Jørgensen

Chen

et al. 2015

Acta Crystallogr Sect B

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Four datasets on [2,2]-paracyclophane were collected in-house and at the Advanced Photon Source at two different temperatures for charge density investigation. Global data quality indicators such as high resolution, high I/σ(I) values, low merging R values and high multiplicity were matched for all four datasets. The structural parameters did not show significant differences, but the synchrotron data depicted deficiencies in the topological analysis. In retrospect these deficiencies could be assigned to the low quality of the innermost data, which could have been identified by e.g. merging R values for only these reflections. In the multipole refinement these deficiencies could be monitored using DRK-plot and residual density analysis. In this particular example the differences in the topological parameters were relatively small but significant.

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“…In a very recent publication, Li et al. observed a similar behavior only in the opposite direction when paracyclophane was subjected to high pressure at room temperature 25…”

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confidence: 84%

Direct Spectroscopic Evidence of the Mechanism behind the Phase Transition of [2,2]‐Paracyclophane

Wolf

Lock

Parker

2015

Chemistry A European J

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[2,2]-Paracyclophane undergoes phase transitions at 45 and 60 K. Based on simultaneous Raman spectroscopy and inelastic neutron scattering experiments (12-70 K), it was shown that a twisting motion of the ethylene bridge perpendicular to the plane of the aromatic rings drives the phase transition. The low-temperature (<45 K) and high-temperature (>60 K) conformers only differ by this twisting motion, which freezes out below 45 K and is thermally averaged above 60 K. Between 45 and 60 K, the system gains energy until the phase transition is complete.

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High-Pressure Raman Study of [2.2]Paracyclophane

Cited by 11 publications

References 41 publications

Structural, dielectric and ferroelectric studies of Ba1−xSrxTiO3 ceramics prepared by mechanochemical activation technique

Structural, dielectric and ferroelectric studies of Ba1−xSrxTiO3 ceramics prepared by mechanochemical activation technique

Charge density investigations on [2,2]-paracyclophane – in data we trust

Direct Spectroscopic Evidence of the Mechanism behind the Phase Transition of [2,2]‐Paracyclophane

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