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| Atomic Physics » Research » Gas phase fullerenes and clusters | ||
| Equipment The main tool that we use to study the dynamics of excited fullerenes is a reflectron time-of-flight mass spectrometer (ReToF). In the ReToF we can excite fullerenes evaporated from an oven and mass separate the produced ions. To find out more about the mass spectrometer click here. The Cold Source We also have the possibility to produce vibrationally cold fullerenes or clusters of fullerenes (or clusters of other molecules too for that matter). This is done in a gas aggregation source called the Cold Source. The cold molcules can then be excited and analyzed in the ReToF. More about the Cold Source here. 
Lasers
To excite our fullerenes we mainly use pulsed lasers. At our disposal we have one N2 laser which gives a wavelength of 337 nm (3.7 eV), an ArF laser which gives 193 nm (6.4 eV), an OPO system which can be tuned between 230 and 2000 nm and a femto second laser system. The ArF laser, which is an excimer laser, can also be used with a F2 gas mix and then gives 157 nm (7.9 eV). With such a high photon energy it is possible to one photon ionise C60 (which has an ionisation energy of 7.6 eV). The fs laser system can work at the fundamental, ca 800 nm, plus the second and third harmonic producing pulses of ca 150 fs. We also have a NOPA which makes it possible to the wavelength from ca 250-1600 nm. The output from the NOPA has a pulselength of ca 20-30 fs. In addition to the lasers we have a filament which emits electrons making it possible to excite and ionise fullerenes by electron impact. |
