Two Purely Inorganic Cationic Tellurite Materials Based on Group IB Metal Tetrafluoroborates with Similar Lamellar Cationic Layers: [Cu 2 F(Te 2 O 5 )](BF 4 ) and [Ag 18 O 2 (Te 4 O 9 ) 4 (Te 3 O 8 )(BF 4 ) 2 ]·2HBF 4 .

Two new purely inorganic cationic tellurite networks of Group IB metal-based tetrafluoroborates, namely, [Cu 2 F(Te 2 O 5 )](BF 4 ), 1 , and [Ag 18 O 2 (Te 4 O 9 ) 4 (Te 3 O 8 )(BF 4 ) 2 ]·2HBF 4 , 2 , have been hydrothermally synthesized under mild conditions. The prepared materials have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, IR and Raman spectroscopy, SEM-energy-dispersive spectroscopy, UV-vis-NIR diffuse reflectance, magnetic study, and TG analyses. Single-crystal diffraction studies show that both materials have similar cationic Cu/Ag tellurite layers with tetrafluoroborates as interlamellar charge-balancing anions. Magnetic results indicate that [Cu 2 F(Te 2 O 5 )](BF 4 ), 1 , exhibits a mainly short-range antiferromagnetic ordering within the 2D layer, and further detailed analysis of magnetic susceptibility analysis confirms a spin-singlet ground state with an energy gap of 85 K.