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Here, we successfully synthesized a pair of enantiomeric molecular piezoelectric materials by H/F substitution strategy. These compounds show a large piezoelectric coefficient d 33 value of 25 pC N -1 measured by the quasi-static method. A simple energy harvesting device was fabricated based on this crystal, showing great potential in piezoelectric mechanical energy harvesters.

Here, we synthesized a series of cholesteryl-based compounds, whose phases and their transformation can be modulated by temperature and the chain length of the fluoroalkyl moieties. To our knowledge, this is the first time that the phase transition could be modulated with perfluoroalkyl tail engineering in organic single-component ferroelectric crystals.

A novel A-site three-dimensional organic-inorganic halide perovskites (3D OIHP) ferroelectric, methylphosphonium tin triiodide (MPSnI 3 ), featuring a narrow bandgap of 1.43 eV, was synthesized. The integration of ferroelectricity with initially moderate efficiency (2.23%) may afford a promising platform to investigate the ferroelectric photovoltaic effect in organic-inorganic halide perovskite solar cells.

Highly enantioselective palladium-catalyzed dearomative reductive Heck reaction and domino Heck-Suzuki reaction of 2-CF 3 -indoles have been developed. Using Pd(OAc) 2 /( R )-Synphos as the catalyst and Et 3 SiH as a hydride source, a variety of indolines bearing a 2-trifluoromethyl quaternary stereocenter were obtained via a dearomative reductive Heck reaction. Alternatively, using Pd(dba) 2 /phosphoramidite as the catalyst and Ar 4 BNa as a coupling partner, structurally diverse indolines containing two vicinal carbon stereocenters were afforded through the domino dearomative Heck-Suzuki reaction.

We discovered that [(histamine)(18-crown-6) 2 ][BF 4 ] 2 is a high-temperature host-guest inclusion complex that presents decent piezoelectric properties ( d 33 = 5 pC/N), undergoes a phase transition at 406 K, and also possesses potential ferroelectricity. This work provides a new idea for constructing host-guest inclusion piezoelectrics.

A host-guest inclusion compound, 18-crown-6 oxonium tetrachloride-gallium(iii), was shown to undergo a 4/mmmFmm2-type ferroelectric phase transition with four crystallographically equivalent polarization directions at 337 K. To the best of our knowledge, this is the first host-guest inclusion compound shown to be a high-temperature multiaxial molecular ferroelectric.

An organic-inorganic hybrid compound, [NH3(CH2)5NH3]SbCl5, exhibits a switchable second harmonic generation (SHG) effect between SHG-OFF and SHG-ON states and tunable dielectric behaviors between high and low dielectric states, connected with the changes in the dynamics of 1,5-pentanediammonium cations during its centrosymmetric-to-noncentrosymmetric symmetry breaking phase transition at 365.4 K.