  Density functional theory (DFT) primarily provides a good description of the
electronic structure. Thus, DFT primarily deals with length scales as those of
a chemical bond, i.e. 10^-10 meter, and with time scales of the order of atomic
vibrations, i.e. 10^-13 seconds. However, several interesting phenomena happen
and/or become observable on different scales, namely meso- or macroscopic
lengths and on time scales of seconds or even minutes. To bridge the gap
between 10^-13 seconds and a second or between 10^-10 meter and 10 and more
nano meters is one of the important challenges we are facing today. In this
paper we show how we are overcoming these time and size problems for the
example of crystal growth and the evolution of nano-scale structures. The key
is a kinetic Monte Carlo approach with detailed input from DFT calculations of
the relevant atomistic processes.
