A Python code for calculating the mean-value (Baldereschi's) point for any crystal structure

Abstract

A python code (mvp.py) is presented for computing the mean-value point (MVP) in the Brillouin zone first introduced by Baldereschi [1]. The code allows calculations of the MVP for any input crystal structure. Having MVP allows approximating the Brillouin zone integrals of relatively smooth, periodic functions defined in the reciprocal space by the value of the same function at only one, mean-value, k-point. This approximation decreases computational cost at a relatively small decrease in accuracy. The MVP coordinates for the 14 Bravais lattices are evaluated and the underlying theory is discussed.