Although I briefly alluded to this in a previous post, it bears some splash on how funny technology and science discussions go. If you want to have fun at some of the public back and forth, read this news flash on microwave heating in organic chemistry, particularly as it applies to polar and non-polar media. I am familiar with the works of all the chemists commenting and publishing. The crux of the biscuit is that one groups says microwave only gives thermal heating while the other groups says there might be other energies involved. Here’s my take on it: 1) for solution phase organic chemistry we have a pretty good handle on measuring temperature changes real time; 2) for heterogenous organic reactions systems (with and without a variety of microwave absorbing metal catalysts) we do not have a predictable way to to measure temperature on the surfaces and rely heavily on the temperature of the bulk media —– well, you can make a career out of saying one thing and later discover that you were wrong one day, but you still made a career…….we are really still trying to couple measurement with phenomenon and for that there is still some handwaving.  Although “the community” has accepted something, as long as there is a clean discrepancy between reaction and measurement, I will keep my cards face down but let all know that I get it.  3) and here is where it is less clean — for inorganic synthesis, we tend to see SUPERHEATING in an exaggerated scale compared with the organikers….of course, my intuition says still that it is still heating and that each new entity (or mix of entities) simply absorb and react under a strict set of rules. It’s headscratching at an all time high…….there is microwave absorption, heterogeneity, kinetics, nucleation events at temperatures greater than the medium, but when all is said and done, the only way to be for sure, is that we have to be able to measure the surfaces of the non-homogeous systems to be completely sure. After all, there is a lot of published work indicating that some crystals formed under microwave conditions can not be duplicated conventionally (thermal, kinetic, superheating, handwaving or should we just wait for the kinetics to catch up on scale).

Schrödinger would be proud of such an exercise. I am going to resolve myself, since I can’t see inside my closed-vessel microwave reactions (I tend to use higher pressure teflon) that someone might be inside doing weird things to my reaction so that we have something to talk about at ACS meetings.

Thermal or something different? Magic behind the closed door

Thermal or something different? Magic behind the closed door

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