The driving power of the quantum superposition principle for molecule-machines

To work, a unimolecular machine will ultimately depend on its preparation in a non-stationary superposition of its quantum states. We provide a description of the possible unimolecular devices or machineries for mechanics, information transmission, molecular electronics and molecular transduction. Experimenting on each category of machines must help to identify the physics behind the quantum superposition principle which is the driving force of most of those machines. This will help in optimizing their design and efficiency in such areas as the motive power for unimolecular mechanical machines, the capacity for molecular transmission channels, the computing power, speed and dissipated energy for molecular electronics and the sensitivity and response time for a unimolecular transducer.