The O-h-[Au-6](2+) cluster exhibits an open-shell 1s(2)1p(2) which trend to a more stable D-2h isomer in 31.5 kcal/mol, as observed in the experimental [Au-6{PC6H4Me-o) pH(2)}(6)] cluster. By taking into account the spin-orbit coupling SOC) in O-h-[Au-6](2+), a resulting 1s(1/2)(2) 1p(1/2)(2) closed-shell superatomic configuration is obtained stabilizing such structure by about 14.7 kcal/mol, decreasing the isomerization barrier. Thus, the spin-orbit term favors the O-h <-> D-2h conformation rearrangement depicting a decrease in the calculated energy difference between both conformations, an interesting consequence which is not obtained in the hypothetical lighter counterparts. (C) 2017 Elsevier B.V. All rights reserved.