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Energy capture photochemistry with ionizing radiation?

Chlorophyll mediates a photochemical reaction: energy from a visible light photon is used to reduce CO2 to CHO, and the energy from that photon can later be recovered when CHO is oxidized back to CO2 in an organism.Is there any analogous photochemical reaction where energy from shorter wavelength ionizing radiation (like Xrays or gamma rays) is captured in a molecule such that it can later be recovered chemically to do work? I do not think any biochemistry happens along these lines but maybe synthetic corroles or porphyrins have been made that...Read more

photochemistry - What fluorescent materials absorb visible light and emit UVC light?

What fluorescent materials, if any, exhibit anti-stokes shift such that they absorb visible light and emit ultraviolet light in the range of 250-285 nm? I'm interested in particular in materials that are efficient in their conversion and not difficult to acquire....Read more

photochemistry - Kinetics energy expression of photon

I need to calculate the kinetics energy of a photon and I'm trying to deduce a correct expression for calculating it. So we have that $K= \frac{1}{2} m_fv_f^2$So $v_f= c$For De Broglie equation we have that $m_f = \frac{h}{\lambda c}$And then $K = \frac{hc}{2 \lambda}$But apparently the correct expression is: $K = \frac{hc}{\lambda}$Can someone help me figure out what I'm doing wrong?Thanks!...Read more

photochemistry - Why does a smaller bandgap correlate to increased absorption of visible light?

I am currently involved in a project on metal organic frameworks in my AP chemistry class, and specifically their applications in $\ce{CO2}$ reduction into formate. All the explanations we can find on why a smaller bandgap correlates to higher absorption and quantum yields refers to PhD-level chemistry, e.g. the Density Functional Theory. Can someone provide a simplified version of this?...Read more

photochemistry - Effect of direct exposure to sunlight on various drugs

Today, we were discussing optical activity in class and our teacher said that some drugs are kept in dark coloured bottles to avoid direct exposure to sunlight. Same is the case with some other drugs in which it's written that the direct exposure to sunlight should be avoided.The reason he gave for the above was that the one form of isomer can get converted to other form in direct sunlight. But as far as i know, photolytic decomposition can happen. Is the conversion of d to l isomer and vice versa possible in sunlight?...Read more

photochemistry - How much heat is created by absorbent-type sunscreens?

I have a friend who claims her dermatologist told her than sunscreen was what was burning her skin. (I think it's much more likely that her rash/burn was either a sunburn, a skin reaction to some other product, or a "sun poisoning" type rash from using a sunscreen that doesn't block UVA -- my wife gets that.)Said doctor told her it's because sunscreen converts the light energy to heat, and that heat was burning her skin. I know this is technically the way those organic sunscreen ingredients work, but can anyone quantify how much heat would actu...Read more

photochemistry - How can I tell if a liquid is (not) emitting light?

I found an image of Nuka Cola Quantim, a soft drink from the Fallout video game series, which depicts the bottle as glowing, but it doesn't feel quite real:Then I also saw this video of a chemiluminescent reaction of luminol:https://youtu.be/TJj7t2mrpxcExperienced chemists and/or photo editors might tell right away which is real and which is fake. What hints should I look for when determining if a liquid itself is glowing or is being lit by a different light source?...Read more