  Anharmonicity of the inter-atomic potential is taken into account for the
quantitative simulation of the conduction and valence band offsets for
highly-strained semiconductor heterostructures. The anharmonicity leads to a
weaker compressive hydrostatic strain than that obtained with the commonly used
quasi-harmonic approximation of the Keating model. Inclusion of the
anharmonicity in the simulation of strained InAs/GaAs nanostructures results in
an improvement of the electron band offset computed on an atomistic level by up
to 100 meV compared to experiment.
