  A definition of quantum mechanical work is introduced in this dissertation,
preserving the mathematical structure of the Classical Mechanics concept of
work without, however, in any way invoking the notion of trajectory. By use of
Gaussian states and the Caldirola-Kanai model, a case study is conducted
through which the proposed quantum work is compared with another Quantum
Thermodynamics well-known definition, both in quantum and semiclassical
regimes, showing promising results. Finally the new definition is investigated
in comparison with a classical-statistical approach for superposition and mixed
states.
