The Exact Schrödinger Equation
The computer-aided calculation of the physical properties of solids is based on the solution of the Schrödinger equation for many electrons ("many-particle problem"):
H Ψ = E Ψ
Unfortunately, even on the best supercomputers it is no longer directly solvable for systems with a few electrons: the wavefunction Ψ of only 10 electrons requires more storage space than is available worldwide.
So how do we deal with millions of electrons in solids?
Research
In the further development of the VASP features, we concentrate on modern methods from quantum field theory and quantum chemistry.
However, the basis for most applications is and remains Walter Kohn's density functional theory. This groundbreaking method allows us to calculate systems with up to several thousand atoms on powerful parallel computers.