Borosulfatesa re compounds analogoust os ilicates, with heteropolyanionic subunits of vertex-linked (SO 4)and (BO 4)-tetrahedra. In contrastt ot he immense structural diversity of silicates,t he number of borosulfatesi sy et very limited and the extent of their properties is still unknown. This is particularly true for representatives with phyllosilicate and tectosilicate analogue anionic substructures. Herein, we present Ni[B 2 (SO 4) 4 ]a nd Co[B 2 (SO 4) 4 ], two new borosulfates with phyllosilicate analogue topology.W hile the anionic subunits of both structures are homeotypic,t he positions of the charge compensating cations differ significantly:N i II is located between the borosulfate layers,w hile Co II-in contrastis embedded within the layer.D etailed analysis of these two structures based on single-crystal X-ray diffraction, magnetochemicali nvestigations,X-ray photoelectron spectroscopy, and quantum chemical calculations, unveiled the reasonsf or this finding. By in silico comparison with other divalent borosulfates, we uncovered systematic trends for phyllosilicate analogues leading to the prediction of new species.
Borosulfates are a rapidly expanding class of silicate analogue materials, where the structural diversity is expected to be at least as large as known for silicates. However, borosulfates with cross-linking of the anionic network into two or even three dimensions are still very rare. Herein, we present two new representatives with phyllosilicate analogue topology. Through solvothermal reactions of ZnO and MnCl2∙4H2O with boric acid in oleum (65% SO3), we obtained single-crystals of Mn[B2(SO4)4] (monoclinic, P21/n, Z = 2, a = 8.0435(4), b = 7.9174(4), c = 9.3082(4) Å, β = 110.94(1)°, V = 553.63(5) Å3) and Zn[B2(SO4)4] (monoclinic, P21/n, Z = 2, a = 7.8338(4), b = 8.0967(4), c = 9.0399(4) Å, β = 111.26(1)°, V = 534.36(5) Å3). The crystal structures reveal layer-like anionic networks with alternating vierer- and zwölfer-rings formed exclusively by corner-linked (SO4)- and (BO4)-tetrahedra.
Borosulfates consist of heteropolyanionic networks of corner-shared (SO4)- and (BO4)-tetrahedra charge compensated by metal or non-metal cations. The anionic substructures differ significantly, depending on the different branching of the silicate-analogous...
Borosulfates are classified as silicate analogue materials. The number of crystallographically characterized compounds is still limited, whereas the structural diversity is already impressive. The anionic substructures of borosulfates exhibit vertex-connected (BO 4 )-and (SO 4 )-tetrahedra, whereas bridging between two (SO 4 )-or even between two (BO 4 )tetrahedra is scarce. The herein presented compound Sr[B 3 O-(SO 4 ) 4 (SO 4 H)] is the first borosulfate with a triple-vertex linkage of three (BO 4 ) tetrahedra via one common oxygen atom. DFT calculations complement the experimental studies. Bader charges (calculated for all atoms) as well as chargedensity calculations give hint to the electron distribution within the anionic substructure and density-of-states calculations support the interpretation of the bonding situation.Mainly, borosulfates are known as glasses. [1] However, elucidation of their crystal structures gained increasing interest for several applications like solid acid polyelectrolytes or NLO materials during the recent years. [2] Up to now, the number of structurally characterized borosulfates is low compared to silicates. Still, the structural diversity is already impressive. The anionic substructures of borosulfates are similar to silicates, exhibiting soro-, neso-, cyclo-, ino-, phyllo-, and tectosilicates like topologies of vertex connected (BO 4 )and (SO 4 )-tetrahedra. [3] Even the formation of S-O-S [3b,c,e, 4, 5] and B-O-B [3i, 6-9] bonds is not uncommon. This finding is in contrast to the structures of alumosilicates, wherein Al-O-Al bonds are not to be expected according to Loewensteins rule. [10] However, also for borosulfates only vertex linkage of two (SO 4 )-or (BO 4 )-tetrahedra, resulting in the formation of (S 2 O 7 )-and (B 2 O 7 )-subunits, is known.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.