KBa3M2F14Cl (M = Zr, Hf): novel short-wavelength mixed metal halides with the largest second-harmonic generation responses contributed by mixed functional moieties

First phase-matchable metal mixed halides with deep-ultraviolet transmittance, KBa 3 M 2 F 14 Cl (M = Zr, Hf), show largest SHG effects coming from isolated MF 7 units, Ba 2+ and Cl − cations. And the optimally aligning MF 7 units work for large birefringence.