C NMR of DIPAC and DIPAB organic ferroelectrics.

The diisopropylammonium chloride (CHClN, DIPAC) and diisopropylammonium bromide (CHBrN, DIPAB) molecular crystals are recently discovered ferroelectrics with sufficiently high spontaneous polarization and Curie temperature. We performed first studies of these crystals by C NMR. CP MAS spectra were collected within large temperature ranges covering the Curie points.

Liquid-liquid transition in supercooled gallium alloys under nanoconfinement.

NMR studies of the thermal evolution of the Ga-In-Sn and Ga-In liquid alloys embedded into opal matrices were carried out. Temperature dependences of the gallium lineshape, shift of the resonance frequency (Knight shift), and intensity were obtained upon cooling down to the alloy freezing and subsequent warming. A second high-frequency Ga NMR signal emerged for both alloys upon cooling, the NMR line intensity transferring gradually into this additional signal.