Using Born-Oppenheimer DFT molecular dynamics we address the stability and non-harmonic vibra-tional effects of the three isomers of hexasulfane at 300 K and 700 K. Both branched structures are stable and dynamic effects introduce large changes to the SAS distances due to the oscillating behavior between ASAS@SASA and ASASAS@SA structures. The largest non-harmonic effects (40%) are found for isomer B in the low frequency region corresponding to the torsional mode coupling the two HS3-S3H moieties. The simultaneous detection of the peaks shifts in the 250 and 800 cm À1 regions could be used to unequivocally characterize these branched hexasulfane isomers in sulfur melts.