Interface calc_elastic_constants

this -- type(MetaPotential), intent(inout)

at -- type(Atoms), intent(inout)

Atoms object for which to compute $C_{ij}$

fd -- real(dp), intent(in), optional

Finite strain to apply. Default $10^{-3}$.

args_str -- character(len=*), intent(in), optional

Optional args_str to pass to minim

c -- real(dp), intent(out), optional, dimension(6,6)

Elastic constants (with relaxation)

c0 -- real(dp), intent(out), optional, dimension(6,6)

Elastic constants (without relaxation)

relax_initial -- logical, optional

Should the initial cell be relaxed?

return_relaxed -- logical, optional

If true, overwrite at with relaxed positions and lattice (default false)

Graphene_Elastic subroutine