# Naming this iron complex: Fe2Cl6[H2O]5

This is the iron complex in question:

$$\ce{Fe2Cl6[H2O]5}$$

I'm pretty sure according to the nomenclature it should be: pentaaquahexachloroiron(III) but I wanted to check somewhere to be sure.

In coordination chemistry square brackets denote inner coordination sphere; $$\ce{[H2O]5}$$ makes little sense in this context. It looks like the correct molecular formula for this compound appears to be $$\ce{[FeCl2(H2O)4]+[FeCl4]- * H2O}$$ according to the crystal structure determined by Szymański [1].
Figure 1. Asymmetric unit $$\ce{[FeCl2(H2O)4]+[FeCl4]- * H2O}$$ (ICSD-8198) with added hydrogen atoms. Color code: $$\color{#EEEEEE}{\Large\bullet}~\ce{H}$$; $$\color{#FF0D0D}{\Large\bullet}~\ce{O}$$; $$\color{#1FF01F}{\Large\bullet}~\ce{Cl}$$; $$\color{#E06633}{\Large\bullet}~\ce{Fe}$$.
1. Szymański, J. T. The Crystal Structure of Tetraaqua-cis-Dichloroiron(III) Tetrachloroferrate(III) Monohydrate (Ferric Chloride $$2\frac 1 2$$-Hydrate). Acta Cryst. B 1979, B35 (9), 1958–1963. https://doi.org/10.1107/S0567740879008244.