Previous research has found that iconic gestures (i.e., gestures that depict the actions, motions or shapes of entities) identify referents that are also lexically specified in the co-occurring speech produced by proficient speakers. This study examines whether concrete deictic gestures (i.e., gestures that point to physical entities) bear a different kind of relation to speech, and whether thi...

We report on a first-principles study of the troilite phase of iron sulfide (FeS). We show that even if, a few decades ago, this material was thought to be ferroelectric, the structural transition from the high P6_{3}/mmc to the low P6[over ¯]2c symmetry phase does not involve polar instabilities, though the space inversion center symmetry is broken. Our calculations and symmetry analysis never...