求助高氯酸根（ClO4-）无序处理的描述？

晶体结构中有个高氯酸根无序了，结构见附件，我对精修过程做了描述，如下：

Specially, the uncoordinated ClO4- in 1 was modelled to be rotationally disordered about Cl1–O3 bond, and then it was divided into two parts, in which O1, O2 and O4 was limited to be 1/2 occupancy for refinement.

审稿意见回来后，审稿人的意思好像是说描述的不对？意见如下，不知道应该如何描述才对？

(c) The disorder of ClO4- is about a special position (2-fold axis);