Euler symmetry not implemented with MPI #38
Description
Currently, the only parts of the Hamiltonian contraction (and I assume some other steps) which can be run using MPI are those corresponding to k-based symmetry, the symmetry used in the H2CO benchmark, for example. The CH4 benchmark fails due to its use of the Euler symmetry, which is not currently supported in the MPI implementation.
Specifically in the Hamiltonian contraction stage (approx line 7740 in perturbation.f90) the function used when euler symmetry is enabled, symm_mat_element_vector, is not MPI-ed while the k-based symmetry version symm_mat_element_vector_k is. Comparing the two functions suggests it would be a few hours worth of work to MPI-ify symm_mat_element_vector. The only other function I can see in perturbation.f90 which is only called when rotsym euler is present is PTrot_contracted_matelem_class.