The rigid rotor and rotational spectroscopy - Real Chemistry

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In this video you will be introduced to the rigid rotor as a model system for rotational spectroscopy. Specifically we will look at the energy eigenvalues for the 3-D rigid rotor and examine how these impact the absorption peaks observed in microwave spectroscopy. We will examine a microwave absorption spectrum in terms of the rotational constant B.
In another video we go through a specific example of calculating bond length from a rational constant:
• Using the rotational c...

[@goldminutes]

This video was really helpful! Your explanations are very clear and straightforward. My lecturer is really great but sometimes it's useful to hear a concept explained in a slightly different way. Thanks

[@RealChemistryVideos]

Glad it was helpful!

[@tunneltrance]

this is a genius video. please make sure it's never deleted from TH-cam

[@Everydaynewsodia]

under rated video

[@calebanderson5309]

How did you determine the 1.5e-9 ev term?

[@liamthompson5787]

Thanks Seth Rogan!

[@tunneltrance]

How is it possible to have condensation inside of a microwave? If you cook a baked potato in a microwave, when your done the walls will have condensation... shouldn't the water vapor inside be most exposed to microwave light... so there won't be any losing of energy to condense on the walls? Because as the microwave is running, you can see condensation build up on the inside glass on the other side of the metal screen

[@JayAyyWhy1231]

Here's my first, nonGoogle-confirmed take: Prior to turning on the microwave, there is some water in the air already as vapor and some in the food as liquid (or ice, if frozen). When the microwave is turned on and water within the food heated, some water molecules near the food surface will gain sufficient energy to escape as vapor and join the ambient vapor. Since now the the vapor content is more saturated than usual, there are more water molecules colliding with the relatively cool glass surface (which also is probably outside the region of peak microwave intensities, which are designed to appear as standing waves at the position of your rotating food). This increases the probability that some will have insufficient energy to reflect from the surface and hence those become bound; more water molecules do this, and added with the tendency for cohesion, condensation begins. I suspect also that an enhancement of the process is not only that there is more water present as vapor, but that out of all the vapors that do escape the food, there are many still close to the liquid-phase binding energy (those which first escaped first with just the minimum acquired energy to do so), rendering them more susceptible for recombination at a surface upon collision.

[@addypharris]

how can I get the bond length if I have the rotational spectra intervals in Hz

[@RealChemistryVideos]

Hi Patrick,
You can use the same process used here, you just need to first covert to wavenumbers. Here is a link to a pdf with the proper equations. Remember if you use the speed of light in m/s that your wavenumbers will come out in m^-1. www2.chemistry.msu.edu/faculty/harrison/cem483/wavenumbers.pdf

[@kirubaharijayakumar5201]

Super video.... I learnt a lot in this video

[@ertanissever7047]

More than excellent.

[@mustakim2144]

Thank you!