*3.1. Structure Descriptions*

The crystal structure of **1** contained one crystallographically nonequivalent U6<sup>+</sup> atom with two short U6<sup>+</sup> <sup>≡</sup> O2<sup>−</sup> bonds (1.768(5) Å), forming nearly linear UO2 <sup>2</sup><sup>+</sup> uranyl ion (*Ur*), which was coordinated by another five oxygen atoms < U1–O*eq* > = 2.356 Å that were arranged in the equatorial plane of the UO7 pentagonal bipyramid. Three of those O*eq* atoms belonged to sulfate tetrahedra, while the other two *cis*-O atoms made an edge shared with the neighbor pentagonal bipyramid, thus forming a dimer. In addition, both O atoms from the shared edge were protonated to form OH− groups. There was one

crystallographically nonequivalent S6<sup>+</sup> atom tetrahedrally coordinated by four O2<sup>−</sup> atoms. U dimers and S-centered tetrahedra shared common vertices to form a layered [(UO2)(SO4)(OH)]<sup>−</sup> complexes (Figure 2a). Being 3-connected, sulfate tetrahedra had the fourth non-shared vertex oriented either *up* or *down* relative to the plane of the layer, which gave rise to geometric isomerism with various orientations of the sulfate tetrahedra. To distinguish the isomers, their orientation matrices were assigned using symbols **u** (*up*) and **d** (*down*). There were two nonequivalent Cs<sup>+</sup> atoms in the structure of **1**, occupying special positions on a mirror plane and arranged in the interlayer space along with substantially vacant and disordered over two sites H2O molecule.

**Figure 2.** 1D and 2D complexes and their respective topologies in the structures of **1** (**a**,**b**), **2** (**c**,**d**), **3** (**e**,**f**), and **4** (**g**,**h**). Legend: U-bearing coordination polyhedra = yellow; S-centered tetrahedra = orange; O atoms = red; H atoms = light grey; black nodes = U atoms, white nodes = S atoms.

There were two crystallographically nonequivalent U6<sup>+</sup> atoms in the structure of **3** with two short U6<sup>+</sup> <sup>≡</sup> O2<sup>−</sup> bonds (1.76(2)–1.80(2) Å), forming *Ur*. The *Ur* cations were coordinated by five oxygen atoms < *Ur*-O*eq* > = 2.35 and 2.37 Å (for U1 and U2, respectively), which belonged to sulfate tetrahedra that were arranged in the equatorial plane of the UO7 pentagonal bipyramid. There were five S6<sup>+</sup> atoms in the structure of **3**, tetrahedrally coordinated by four O2<sup>−</sup> atoms each. All sulfate tetrahedra were 2-connected, having only two vertices shared with the uranyl bipyramids, while the other two vertices were left non-shared. But if S1-, S3-, and S5-centered tetrahedra shared two of their vertices with two *Ur* polyhedra, S2- and S4-centered tetrahedra linked to the single bipyramid via sharing a common edge. U and S coordination polyhedra shared common vertices and edges to form wave-like infinite chains of [(UO2)2(SO4)5] <sup>6</sup><sup>−</sup> composition (Figure 2e). Besides, the linkage of coordination polyhedra inside the chain occurred only via corner-sharing, while edge-shared sulfate tetrahedra decorated the exterior of the chain. Uranyl sulfate chains were interlinked into the pseudo layered structure via an H-bonding system involving H2O molecules. The negative charge of the uranyl sulfate complex was compensated by six Cs<sup>+</sup> cations arranged in between the pseudo layers. It should be noted that three sites occupied by H2O molecules were localized only in the voids arranged in the plane of the chains but not between the pseudo-2D complexes.

There was one crystallographically nonequivalent U6<sup>+</sup> atom in the structure of **4** with two short bonds (< U1–O*Ur* > = 1.772 Å) forming Ur, which was coordinated by five oxygen atoms < *Ur*-O*eq* > = 2.38 Å, belonging to sulfate tetrahedra and arranged in the equatorial plane of the pentagonal bipyramid. Two nonequivalent S6<sup>+</sup> atoms were tetrahedrally coordinated by four O2<sup>−</sup> atoms each. There were two types of sulfate oxyanions: [S1O4] <sup>2</sup><sup>−</sup> were 2-connected, sharing two vertices with two adjacent *Ur* polyhedra, and [S2O4] <sup>2</sup><sup>−</sup> were 3-connected (chelating-bridging), sharing vertex with one uranyl bipyramid and an edge with the neighbor one. The structure of **4** was based on the layered complexes of [(UO2)(SO4)2] <sup>2</sup><sup>−</sup> composition (Figure 2g), interlinked by the two non-equivalent Cs<sup>+</sup> cations.
