Microwave chemistry primarily focuses on the efficient use of energy and can enhance reaction rates, often improving atom economy and safety. In this context, the principle that does NOT align well with microwave chemistry from the provided options is:
D. Safer chemicals and products
While microwave chemistry can indeed aid in producing safer chemicals and products by allowing for milder reaction conditions and minimized byproducts, this principle is more about the inherent safety of the chemicals used and the end products rather than a direct feature of microwave technology itself. The other principles—maximizing atom economy, safer solvents, and increasing energy efficiency—are more closely tied to the advantages brought by microwave-assisted reactions.