3 ms·
Again, not a physicist. But my understanding is that on a femptosecond timescale (the duration of the x-ray pulse generated by LCLS-II), effectively no reaction
by eslaught 3y ago
Again, not a physicist. But my understanding is that on a femptosecond timescale (the duration of the x-ray pulse generated by LCLS-II), effectively no reactions occur. The pulse destroys the sample, so that means you have to pump through a steady stream of sample particles to image. So for any given experiment, you'll get a stream of what are effectively snapshots of the reaction occurring at a given moment in time, and then it's up to software post-processing to figure out what you're looking at in a given snapshot and how far progressed the chemical reaction is at that point.
- natechols 3y agoI helped with similar experiments at LCLS-I and the first half of this comment is correct. The chemical reaction is carefully timed on the order of milliseconds, so they get a series of snapshots of the reaction at a specific known state (but previously unknown structure). There isn't enough information in individual snapshots for the processing software to do very much with besides combine it with other snapshots (thousands of them).