Abstract: Through reductive addition of phLi to μ-S₂Fe₂(CO)₆ and nucleophilic substitution between RXand (μ-PhS)(μ-LiS)Fe₂(CO)₆ nine clusters of (μ-PhS)(μ-RS)Fe₂(CO)₆ series (Ⅰ) -(Ⅸ) have been synthesized successfully.It is shown that yields of clusters (Ⅰ) -(Ⅸ) and reactivities of RXin nucleophilic reactions depend on both structures of Rand nature of X.And according to chemical shift and integrated values of related signals of ¹HNMRpossible isomers and isomcr ratios of some clusters have been determined.In addition, it is suggested that diamagnetic aniso-tropic effects of C = Oand orientations of unshared electron pairs are likely responsible for systematic variations in δ CH₃-Sand δ CH₂-Sof cluster isomers.