Consideration of dielectric relaxation of pure DMSO liquid in different temperatures

•The Kirkwood factor with different conditions needs reinterpretation.•CC model generally depicts molecular cooperative interactions with single channel.•DC model couples multi-channels, including various relaxation modes.

This paper mainly analyzes the relaxation process of both CC model and Davidson–Cole (DC) model, depicting the process by relaxation time, broadening parameter and temperature dependent Kirkwood correlation factor. The Kirkwood correlation factor of CC model in adjustable infinite dielectric constant is more changeable with temperature than DC model. The Kirkwood factor with different conditions needs reinterpretation. CC model generally depicts molecular cooperative interactions with single channel and evaluates once relaxation act of DMSO cluster within a cutoff time. DC model couples multi-channels, including various relaxation modes such as monomeric, dimeric and cluster. So the relaxation time of DC model is higher than CC model.