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Name: Brittany
Status: student
Age: 17
Location: N/A
Country: N/A
Date: 1999 

How can one measure the change in the EM field around an atom when it absorbs light?

I am trying to do this for a project. I found a cool concept but i don't know if it could work. I came up with the idea based on this website

Basically it says " an atom behaves as an electromagnetic resonator similar to a coil/capacitor tank circuit, and if the resonant frequency of the "atom/circuit" is the same as the frequency of the light, then the atom will absorb a tiny bit of an incoming light wave and store it as a region of oscillating EM fields. These fields would surround the atom. Oddly, these fields strongly interact with the incoming light because they are naturally phase-locked to it. "

Would this work? Could i make different solutions with different compounds and explore how much light can be it can absorb in these region of oscillating EM fields if i have atoms of greater radius, molecule with high energy bonds, changing variables around.

Basically make different solutions then use a spectrophotometer to see how much light is absorb. (naturally i would you colorless compounds). Or does that not work, are the spectrophotometer dependant on a color change? Or are they not that sensetive? is a uv spectrophotmeter more sensetive? Since it creates a EM field, is there another way i could measure it?

Basically, this "electromagnetic resonator" explanation just is another way of describing how atoms and molecules absorb light. The energy from the absorbed light excites electrons to higher energy states, in which their magnetic properties are different. I don't understand exactly what you would be measuring in your proposed experiments. Measuring light absorption is easy with a spectrophotometer; that's what they do. I don't get what you'll be doing with the EM fields.

If you want your solutions to absorb light, you'll need to use colored compounds. Colorless compounds simply don't absorb light. That's why they're colorless.

I don't think I've fully answered your question, but I'm not quite certain where I need to begin explaining the principles of photochemistry to you. Clarify and ask again, if you wish.

Richard E. Barrans Jr., Ph. D.

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