Q2. What is the reason for the mixed clusters?
A filling of the first solvation shell results in an abrupt decrease of the binding en-ergy as is manifested by a pronounced intensity step at n= 12 (i.e. for 13 atoms).
Q3. What is the basic idea of the pulsed arc cluster ion source?
there is still the need to have a laser to excite the source, i.e. discharge energy is transformed into light, which carries the energy into the source and produces the plasma.
Q4. What is the basic idea of the PACIS?
the basic idea of the PACIS is the replacement of the vaporizing laser by a pulsed high-current arc between two electrodes in a pulse of carrier gas, which flushes the nascent plasma through a channel and conical nozzle into high vacuum.
Q5. What is the voltage of the pulsed arc cluster?
The applied voltage ranges from 300 to 1200 V. A pulsed carrier gas valve (General Valve, Ser. 9, backing pressure z 15 bar) is attached to the ceramic block and flushes the resulting plasma through a 2 mm wide and 20 mm long channel into a conical nozzle (IO”, 30-60 mm long).
Q6. What was the first method of producing clusters?
For high melting point materials the production of “cold” clusters was not possible until Bondybey and English [4] and Dietz et al. [ 51 introduced the concept of laser vaporization (of nearly any solid material) and subsequent cluster growth in a stream of a cold carrier gas.
Q7. What is the effect of the ion pulse on the mass of the tungsten?
This setup turned out to induce nearly no mass discrimination, i.e. the whole ion pulse can be mass analyzed by timeof-flight measurement without the need of correction fields [ 7,8 1.
Q8. What is the description of the clusters?
These measurements strongly support the close packing model for argon and krypton clusters containing a central ion “ solvated” by the surrounding atoms.