Microwave dipolar water molecule rotation

Microwaves are a form of electromagnetic radiation produced in magnetrons, which can be absorbed by a process called dielectric heating. Dipolar molecules, e.g., water, undergo rotation in order to try to align... 

Aromatic plants are usually constituted from cellulose, essential oil, and water. If these three compounds are heated by microwaves at a fixed radiation power and for a set time, the heating rate will be the highest for water, followed by essential oil and cellulose, respectively. One of the interactions of the microwave energy with the matrix is called the dipolar polarization mechanism. A substance can generate heat when irradiated with microwaves if it has a dipole moment, for example that of the water molecule. A dipole is sensitive to external electric fields and will attempt to align itself with the field by rotation. 

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