Exploration of structural, thermal and vibrational properties of new noncentrosymmetric double borate Rb3Tm2B3O9

Double borate Rb3Tm2B3O9 was newly synthesized by solid-state reaction. The crystal structure of Rb3Tm2B3O9 was refined by Rietveld's method: Pna2(1), alpha = 8.6648(1), b = 9.5238(1), c = 12.1722(1) angstrom, Z = 4. The crystal structure of Rb3Tm2B3O9 consists of -[Tm2O9](infinity)- chains along the a axis. BO3 triangles linked chains in a threedimensional framework. Rubidium atoms occupied empty ones in channels. The thermal behavior of Rb3Tm2B3O9 was studied in detail in between 25 and 1200 degrees C by DSC and TG methods. Rb3Tm2B3O9 was congruently melted at 886 degrees C. The band gap is found as E-g similar to 5.14 eV. Nonlinear optical response of Rb3Tm2B3O9 tested via SHG is estimated to be lower than that of KDP. The existence of BO3 groups in Rb3Tm2B3O9 crystal structure has been confirmed by an IR analysis.

Automated summary

In this study, the double borate Rb3Tm2B3O9 was successfully synthesized by solid-state reaction, and its crystal structure and thermal behavior were extensively investigated. The compound exhibited a large band gap energy and a lower nonlinear optical response compared to KDP, with the presence of BO3 groups confirmed through IR analysis.