Abstract
The development of nonlinear optical (NLO) materials has been hindered by competing microstructure requirements: the need to simultaneously engineer a large hyperpolarizability (a large second-harmonic generation (SHG)) and a wide HOMO-LUMO gap (a wide band gap). Herein, a non-centrosymmetric transition-metal (TM) oxyfluoride K5 (NbOF4 )(NbF7 )2 (KNOF) with an extremely high F/O ratio is constructed in high yield. KNOF exhibits an extremely wide band gap (5.88 eV) and a strong powder SHG response (4.0×KH2 PO4 )-both being the largest values for TM-centered oxyfluorides-as well as a birefringence sufficient for applications. The dominant roles of the partially fluorinated [NbO2 F4 ] and totally fluorinated [NbF7 ] groups in achieving the enlarged band gap in KNOF have been clarified by first-principles calculations. Our results suggest that maximizing the fluorine content of oxyfluorides may unlock the promise of short-wavelength-transparent materials with exceptional NLO performance.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.