| Date | May 2015 | Marks available | 1 | Reference code | 15M.3.sl.TZ1.9 |
| Level | SL | Paper | 3 | Time zone | TZ1 |
| Command term | Outline | Question number | 9 | Adapted from | N/A |
Question
In 1989 Don Eigler and his team carried out one of the first experiments in nanotechnology.
They spelled out the IBM logo with 35 xenon atoms.
Outline the technique used to manipulate the atoms in this way.
The atomic radius of xenon is \(1.36 \times {10^{ - 10}}{\text{ m}}\). Estimate the approximate length, in m, of the “I” in the original IBM image.
Markscheme
physical;
atoms placed in specific positions;
using a scanning tunnelling microscope/STM / atomic/scanning force microscope/AFM/SFM;
Accept “using a scanning probe/device/instrument”.
any value in the range \({10^{ - 9}}-{10^{ - 8}}{\text{ (m)}}\);
Examiners report
Manipulating the atoms using an atomic force microscope was not well known.
With the help of the given diagram some candidates were able to estimate a reasonable length. The range of length accepted in the markscheme was generous.
