Preparation and crystal structure of a new uranyl sulfate templated by a bis-isothiouronium cation

Crystals of a new uranyl sulfate /((C_2 N_4H_8 S_2)[UO_2(SO_4)_2] /cdot 0.3H_2O/) (1) templated by a relatively rare bis-isothiouronium cation, were formed upon evaporation of aqueous solutions containing uranyl acetate, thiourea, and excess sulfuric acid. The new compound is orthorhombic, $P{2}_1{2}_1{2}_1$, a = 6.928(2) Å, b = 13.398(3) Å, c = 15.225(3) Å, Z = 2. Its crystal structure is comprised of /([UO_2(SO_4)_2]/) moieties linked by hydrogen bonds formed between the template cations and terminal oxygen atoms of the sulfate tetrahedra. The $C_2{N}_4{H}_8{S}_2^{2+}$ template is most likely formed in situ during a redox reaction between uranyl cation and thiourea in a strongly acidic medium, with $U{O}_2^{2+}$ partially reduced to $U^{4+}$. (© 2020 WILEY‐VCH Verlag GmbH and Co. KGaA, Weinheim)