Be2(BO3)(IO3): The First Anion-mixed Van der Waals Member in the KBe2BO3F2 Family with a Very Strong Second Harmonic Generation Response

To obtain new nonlinear optical (NLO) materials with a large second harmonic generation (SHG) effect has always been a great challenge. We have synthesized the first metal borate-iodate NLO crystal, Be-2(BO3)(IO3) (BBIO), by multicomponent modification of KBe2BO3F2 (KBBF), in which the structural features of KBBF were maintained and (IO3)(-) groups were connected to honeycomb [Be2BO3O2](infinity) layers. As the first KBBF family member with mixed anionic groups, BBIO benefited from the synergistic effect of (IO3)(-), (BO3)(3-) and (BeO4)(6-) groups, and exhibited a very strong SHG response of approximate to 7.2xKH(2)PO(4) (KDP, @1064 nm) and a large birefringence (Delta n) of 0.172 at 1064 nm. BBIO may, unexpectedly, optimize growth habits via van der Waals forces. This study presents borate-iodate as a new NLO material and it demonstrates opportunities in KBBF structural engineering.

Automated summary

A new metal borate-iodate NLO crystal, BBIO, was synthesized with strong SHG response and large birefringence. The study also suggests that BBIO may optimize growth habits via van der Waals forces. Opportunities in KBBF structural engineering were demonstrated in this research.