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We report temperature dependent electron paramagnetic resonance (EPR) studies on polycrystalline YCrO₃ samples at X-band (9.46 GHz) in the temperature range of 120 K to 298 K. The EPR spectra exhibit a single broad line across the whole temperature range, attributed to Cr³⁺ ions. The variation of EPR spectra parameters (line width, integrated intensity, and g-factor) as a function of temperature was analyzed to understand the nature of spin-dynamics in the paramagnetic region of YCrO₃. A peak in the g-factor suggests the presence of a new phase within the paramagnetic state at an intermediate point of temperature <i>T</i>_IP ~ 230 K, attributed to the onset of short range canted antiferromagnetic correlations in the material much above 140 K, Néel temperature (<i>T</i>_N) of YCrO₃. The EPR intensity increases with a decrease in temperature up to <i>T</i>_N due to the renormalization of the magnetic moments arising from the appearance of canted antiferromagnetic correlations. Further, temperature dependent dielectric measurements also exhibit an anomaly at ~ 230 K suggesting the presence of magnetodielectric coupling in YCrO₃, with a possibility towards a relatively high temperature magnetodielectric system.

THBP-GFO nanocrystals with novel structural symmetry demonstrate impressive self-cleaning property.

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A total of six TGMS (thermosensitive genic male sterile lines) and nine pollinator lines were subjected to molecular characterization using 48 genome-wide SSR (simple sequence repeat) markers. Cluster analysis revealed clear differentiation among the TGMS lines according to their source of origin. The SSR-based genetic distance between the hybrids of the parental lines ranged from 0.36 to 0.79 suggesting a high degree of genetic divergence. Among a set of 54 hybrids generated using parental lines, 32 showed better parent heterosis (+21.7%) while 19 showed mid-parent heterosis (+15.0%). For the trait yield per plant genetic distance (GD) was negatively correlated with F1 performance (r = -0.202), mid-parent heterosis (r = -0.325*; P < 0.05), and better parent heterosis (r = -0.261), while it was positively correlated with specific combining ability (r = 0.042). Based on the grouped genetic distance (GGD), the hybrid combinations were divided into four groups. The GGD showed linear correlation with hybrid performance within the group (GGD = 40 -50: r = -0.07; GGD = 70 -80: r = 0.32). This information can be utilized in the development of higher yielding, two-line rice hybrids through selection of intermediately diverse parental lines using GGD.

In this paper, we report the X‐ray diffraction studies over the temperature range of 300–900 K and subsequent Rietveld refinement of the diffraction patterns shows that there is no evidence of any structural phase transition in YCrO3 (YCO) across the paraelectric to ferroelectric phase transitions (TC ~ 460 K), and the material retains the orthorhombic structure with Pnma space group. However, a detailed analysis reveals local distortions in the CrO6 octahedra. To probe the local structural distortion, we have carried out temperature‐dependent, unpolarized Raman measurements, from 300 to 600 K. YCrO3 shows a strong anomalous deviation in both phonon wavenumbers and line widths around TC. YCrO3 is reported to possess as an incipient ferroelectric material to show that there are two competing phenomenon—onset of ferroelectricity due to rotation of CrO6 octahedra and displacement of Y atom leading to suppression of ferroelectricity. This competition reveals that although the octahedral rotations favor a lower symmetry state, the Y atom displacement opposes it leaving YCO to exhibit only an incipient ferroelectric state. These results while being in agreement with the earlier theoretical predictions can also help suggest a pathway to a more stable ferroelectric state in these oxides by using a larger cationic substitution at the Y site.

We demonstrate that small but finite ferroelectric polarization (∼0.01 µC/cm 2 ) emerges in orthorhombic LuFeO3 (P nma) at TN (∼600 K) because of commensurate (k = 0) and collinear magnetic structure. The synchrotron x-ray and neutron diffraction data suggest that the polarization could originate from enhanced bond covalency together with subtle contribution from lattice. The theoretical calculations indicate enhancement of bond covalency as well as the possibility of structural transition to the polar P na21 phase below TN . The P na21 phase, in fact, is found to be energetically favorable below TN in orthorhombic LuFeO3 (albeit with very small energy difference) than in isostructural and nonferroelectric LaFeO3 or NdFeO3. Application of electric field induces finite piezostriction in LuFeO3 via electrostriction resulting in clear domain contrast images in piezoresponse force microscopy.

In this manuscript, we report the 89Y NMR measurement as a function of temperature on single phase and pure polycrystalline YCrO3 sample to study the magnetism and relaxation times on a microscopic level across the magnetic transition (T N ≃ 141 K) from paramagnetic to antiferromagnetic state. The NMR peak width broadens abruptly upon crossing T N due to the onset of internal magnetic fields, while peakshift slight decreases. A slight increase and subsequent anomalous decrease in the NMR peak intensity is observed on approaching T N from 300 K. There is also a significant increase in peak width. The temperature dependence of the 89Y NMR spin–lattice relaxation rates 1/T 1 indicates a phase transition at T N which is of magnetic origin due to Cr3+ ions, with an anomalously rise of fluctuations below T N. Above T N, this spin–lattice relaxation rate can be fitted to a power-law scaling behavior 1/T 1 ∼ T β with an exponent factor β ≈ 0.8, indicates low energy spin fluctuations. Moreover, Knight shift and 1/TT 1 scales linear with the bulk susceptibility which suggests the antiferromagnetic spin fluctuation in the YCrO3 system.