Crystal structures of (a) Fe2(MoO4)3and (b) A2Fe2(MoO4)3. (c) Formation energies ofAxFe2(MoO4)3at differentxvalues (A= Li or Na). Optimized lattice parameters of (d) LixFe2(MoO4)3and (e) NaxFe2(MoO4)3at differentxvalues.[81]