A molecular gyroscope having phenylene rotator encased in three-spoke silicon-based stator

A molecular gyroscope which has a phenylene rotator encased in three long siloxaalkane spokes was synthesized. The phenylene ring is observed by X-ray crystallography at three rotational positions around the 1,4-axis between 223-303 K. The area in which the phenylene ring is found is significantly reduced at 173 K owing to the deformation of a siloxaalkane spoke; the temperature-dependent phenylene disorder is reversible.