Many, if not all, of the compounds listed here have sub-stoichiometric occupation on the (1a) site. The site is reported as fully occupied in InNbS$_{2}$, which is why we and the ICSD choose it as the prototype of the structure, even though (Eppinga, 1980) give it as Tl$_{x}$TaS$_{2}$.
The value $z_{3}$ = 0.32 for the sulfur (2c) site is inferred from the value given for Ta$_{x}$InSe$_{2}$ by (Eppinga, 1980).
$\frac{1}{2}a \,\mathbf{\hat{x}}+\frac{\sqrt{3}}{6}a \,\mathbf{\hat{y}}- c z_{3} \,\mathbf{\hat{z}}$
(2h)
S I
References
R. Eppinga and G. A. Wiegers, A generalized scheme for niobium and tantalum dichalcogenides intercalated with post-transition elements, Physica B+C 99, 121–127 (1980), doi:10.1016/0378-4363(80)90219-3.
Found in
R. Sankar, G. N. Rao, I. P. Muthuselvam, G. Bian, H. Zheng, G. P.-J. Chen, T.-R. Chang, S. Xu, G. S. Murgan, C.-H. Lin, W.-L. Lee, H.-T. Jeng, M. Hasan, and F.-C. Chou, Single crystal growth and physical property characterization of PbTaSe$_{2}$ as a noncentrosymmetric type-II superconductor, doi:10.48550/arXiv.1511.05295. ArXiv:1511.05295 [cond-mat.supr-con] (We have not been able to find an archival reference for this paper. Users who know of such a reference are encouraged to contact us.).
First cited in
N. Anderson, M. J. Mehl, H. Eckert, S. Divilov, X. Campilongo, S. Curtarolo, The AFLOW Library of Crystallographic Prototypes: Part 5. Submitted to Computational Materials Science (2026).