Triple‐Vertex Linkage of (BO4)‐Tetrahedra in a Borosulfate: Synthesis, Crystal Structure, and Quantum‐Chemical Investigation of Sr[B3O(SO4)4(SO4H)]

• Published in: Angewandte Chemie International Edition Vol. 60; no. 36; pp. 19740 - 19743
• Main Authors: Pasqualini, Leonard C., Huppertz, Hubert, Je, Minyeong, Choi, Heechae, Bruns, Jörn
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.09.2021; John Wiley and Sons Inc
• Edition: International ed. in English
• Subjects: borosulfates; Charge density; charge-density calculations; Chemical synthesis; Communication; Communications; Crystal structure; Crystallography; density functional theory; density of states; Electron distribution; Mathematical analysis; solvothermal synthesis; Tetrahedra
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202106337

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 (BO4)‐ and (SO4)‐tetrahedra, whereas bridging between two (SO4)‐ or even between two (BO4)‐tetrahedra is scarce. The herein presented compound Sr[B3O(SO4)4(SO4H)] is the first borosulfate with a triple‐vertex linkage of three (BO4) tetrahedra via one common oxygen atom. DFT calculations complement the experimental studies. Bader charges (calculated for all atoms) as well as charge‐density calculations give hint to the electron distribution within the anionic substructure and density‐of‐states calculations support the interpretation of the bonding situation. Sr[B3O(SO4)4(SO4H)] was obtained under harsh conditions in a specially designed setup. In contrast to silicates and its substitution variants like alumosilicates, the anionic substructure of Sr[B3O(SO4)4(SO4H)] reveals vertex linkage of three (BO4) tetrahedra via a common oxygen atom. DFT calculations help to elucidate the nature of this special bonding situation.