keywords BARRIERS COMPLEXES CORANNULENE DISPLACEMENT-REACTIONS DYNAMIC-BEHAVIOR INVERSION Multidisciplinary Sciences RAY CRYSTAL-STRUCTURE ROTATION SILATROPIC SHIFTS Science & Technology Science & Technology - Other Topics TRANSITION-METAL alkene rotations corannulenes diastereotopic groups hexaalkylbenzenes indenylsilanes mixed metal clusters molecular brakes polyphenylated rings sigmatropic and haptotropic shifts tripodal rotations triptycenes