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Organic single-component ferroelectrics with low molecular mass have drawn great attention for applications in organic electronics. However, the discovery of high-Tc single-component organic ferroelectrics has been very scarce. Herein, we report a pair of homochiral single-component organic ferroelectrics (R)-10-camphorsulfonylimine and (S)-10-camphorsulfonylimine under the guidance of ferroelectric chiral chemistry. They crystallize in chiral-polar space group P21, and their mirror image relations have been identified by vibrational circular dichroism spectra. They both exhibit 422F2 multiaxial ferroelectricity with Tc as high as 429 K. Besides, they possess superior acoustic impedance characteristic with the value of 2.45×106 kg·s-1·m-2, lower than that of PVDF. To our knowledge, enantiomeric (R and S)-10-camphorsulfonylimine show the highest Tc among the known organic single-component ferroelectrics and the low acoustic impedance well matching with the bodily tissues. This work promotes the development of high-performance organic single-component ferroelectrics and is of great inspiration to explore the applications in next-generation flexible smart devices.

H/F substitution successfully constructs unprecedented switchable C–F–K coordination bonds in a three-dimensional cyano-bridged double perovskite ferroelastic [(CH3)3NCH2F]2[KFe(CN)6].

Chirality exists everywhere from natural amino acids to particle physics. The introduction of point chirality has recently been shown to be an efficient strategy for the construction of molecular ferroelectrics. In contrast to point chirality, however, axial chirality is rarely used to design ferroelectrics so far. Here, based on optically active 1,1'-bi-2-naphthol (BINOL), which has been applied extensively as a versatile chiral reagent in asymmetric catalysis, chiral recognition, and optics, we successfully design a pair of axial-chiral BINOL multiferroics, (

The optical manipulation of polarization has gained widespread attention because it offers a promising route to new contactless memories and switches. However, the current research basically focuses on the photocontrol of data storage rather than data reading, which cannot realize the whole process of contactless write-read-erase data storage. Here, we present a pair of enantiomorphic diarylethene derivative ferroelectric crystals, showing a light-driven phase transition triggered by photoisomerization between the open and closed forms. Under the visible light, they exhibit a binary-domain state in the open form with white color and the band gap of 3.26 eV, while they show a single-domain state in the closed form with blue color and the band gap of 1.68 eV after UV irradiation of 254/365 nm. In addition to writing and erasing ferroelectric domains with light, we can also use light to read their color to determine the polarization state of domains. Moreover, diarylethene derivatives have better thermal stability, higher photoexcited conversion efficiency, and larger changes of the absorption wavelength between two isomers than those in salicylideneaniline derivatives. This work not only discovers the first diarylethene-based ferroelectric crystals but also successfully realizes completely contactless manipulation of write-read-erase data storage in the organic ferroelectric semiconductors.

Many indexes have been demonstrated to evaluate the lodging resistance of rice, but most of them are complex or not representative. Thus, we propose a simple and low-cost index, called relative culm wall thickness (RCWT), which can be calculated as the ratio of the basal internode wall thickness to its diameter, to measure the lodging characteristics of rice. A field experiment with 20 indica hybrid rice varieties was conducted in Dayi, Sichuan, China, in 2017 and 2018. The results show that RCWT was significantly negatively correlated with the lodging index, visual lodging rate, plant inclination angle, and bending moment, while it was significantly positively correlated with culm wall thickness, breaking resistance, cellulose, and lignin. Compared with the middle and low RCWT types, the high RCWT type had a lower plant height and center of gravity. Meanwhile, the short basal internodes, thick culm wall thickness, and small pith diameter increased the fullness of the stem, which increased the content of cellulose and lignin in the stem, and thus enhanced the bending resistance and decreased lodging index of the stem. These results indicate that the RCWT can be used as an important index to evaluate the lodging resistance of rice.

A ferroelectric/ferroelastic is a material whose spontaneous polarization/strain can be switched by applying an external electric field/mechanical stress. However, the optical control of spontaneous polarization/strain remains relatively unexplored in crystalline materials, although photoirradiation stands out as a nondestructive, noncontact, and remote-controlled stimulus beyond stress or electric field. Here, we present two new organic single-component homochiral photochromic multiferroics, (