Our previously reported implementation of SOC calculations within the EOM-CCSD framework enables calculations between the selected target EOM states. In a typical non-relativistic EOM-CC calculation (and in many other excited-state calculations), one computes only one component of the target multiplet because other components are exactly degenerate. For example, traditionally only M s =0 components of triplet states are computed. This is obviously insufficient for computing the full SOCC matrix. One possible strategy is to explicitly compute two other components (M s =±1), which requires additional coding efforts and increases the cost of the calculations. In addition, a special care needs to be taken to synchronize the phases of all computed states . Alternatively, one can apply coordinate rotations (which is equivalent to changing the quantization axis) and extract the SOC matrix elements in the original coordinate frame from the matrix elements in the rotated frames. However, practical application of this approach is also complicated by the phase problem mentioned above: the phases of the wave functions computed in different coordinate frames are arbitrary. In addition, frame rotations may require disabling point-group symmetry, thus further increasing the cost of calculations.