the hydrogen atom is shy; it doesnt like to have its picture taken; but researchers in the netherlands has broken hydrogen out of its bubble, so to speak. they took the first ever picture of hydrogen's electron cloud. these clouds have been imaged before; from nitrogen molecules [2] to Xe atoms [3], the electron cloud has had no escape from the leer of the camera. what sets this study apart is the method of detection.
they isolate a hydrogen atom; shoot it with a 243 nm pulsed laser to excite the atom; shoot it 'fourier-limited tunable' 365 nm laser to release the electrons; these electrons are now called photoelectrons; they are accelerated by a 808 V/cm electric field (perpendicular to the detector); they move across an einzel lens that magnifies it by one order of magnitude; they stick onto a phosphor screen with microchannel plates; where it is recorded using a CCD camera. [1]
this detection method accurately depicts the distribution of electrons around the hydrogen atom. as it turns out, the electron mapping correlates well with the schrodinger's equation for the system, thus providing (the first?) experimental evidence for the wave function of hydrogen. the concept for this experiment has been in the literature for 30 years [4]; everything from the use of ionized hydrogen to the position of the detector perpendicular to the electric field was proposed long before the experiments where conducted.
this just goes to show that we need more people willing to do these impotent experiments, so we can get things done in a timely fashion. of course no blame is to be made to the 9 people conducting this experiment, they did an excellent job and jolly good for them but in the future we should strive to conduct experiments right after the theoretical predictions are made public. that is the way forward for science, and that is the right way to detect electron clouds.
-josh mitri
-josh mitri
No comments:
Post a Comment