Relativistic magnetic quadrupole transitions in Be-like ions

The multiconfiguration Dirac-Fock method, based on the extended optimal level approximation, is used to calculate magnetic quadrupole transitions (M2) from 2s2p(P-3(2)) to 2s(2)(S-1(0)) states in berylliumlike ions. The calculation of this transition for Z>6 uses the Dirac-Fock Hamiltonian which is necessary for highly ionized atoms. The Breit interaction is treated as a first-order perturbation, and;its non-negligible contributions to the excitation energies for heavier ions are highlighted. Some of the M2 transition probabilities results presented in this paper are calculated for the first time, to our knowledge.