27:. The main effect of the absorption of microwaves by dielectric materials is a brief displacement in the permanent dipoles which causes rotational entropy. Since the frequency of the microwave energy is much faster than the electrons can absorb, the resultant energy can cause frictional heating of nearby atoms or molecules. If the material is rigid there will be no release of rotational energy, and therefore no heating. There are no "Non-thermal effects". If the material is not a dielectric material with dipoles or an ionic distribution, there is no interaction with microwaves and no heating. Non-thermal effects in liquids are almost certainly non-existent, as the time for energy redistribution between molecules in a liquid is much less than the period of a microwave
31:. A 2005 review has illustrated this in application to organic chemistry, though clearly supports the existence of non-thermal effects. It has been shown that such non-thermal effects exist in the reaction of O + HCl(DCl) -> OH(OD) + Cl in the gas phase and the authors suggest that some mechanisms may also be present in the condensed phase. Non-thermal effects in solids are still part of an ongoing debate. It is likely that through focusing of
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processes. Debates continued in 2006 about non-thermal effects of microwaves that have been reported in solid-state phase transitions. A 2013 essay concluded the effect did not exist in organic synthesis involving liquid phases. A 2015 perspective discusses the non-thermal microwave effect (a
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