Space groups, metal–oxyhalide unit types, and key properties of NLO metal oxyhalides with mixed halogen anions.
| No. | Crystal | Space group | Metal–oxyhalide unit type | SHGa | E g (eV) | Birefringence | IR cutoff edge (μm) | LDT (MW cm−2) |
|---|---|---|---|---|---|---|---|---|
| 1 | Pb13O6Cl9Br5 (ref. 64) | Fmm2 | Multiple [PbO2ClmBrn] | 0.9× AGS | 3.23 | — | 14.0c | 439e |
| 2 | Pb13O6Cl7Br7 (ref. 64) | Fmm2 | Multiple [PbO2ClmBrn] | 0.8× AGS | 3.13 | — | 6.0b | — |
| 3 | Pb13O6Cl4Br10 (ref. 64) | Fmm2 | Multiple [PbO2ClmBrn] | 0.6× AGS | 3.05 | — | 6.0b | — |
| 4 | Pb18O8Cl15I5 (ref. 65) | Cc | Multiple [PbOClmIn], [PbO2ClmIn], [PbO3ClmIn] | 1.05× AGS | 2.82 | 0.086@636 nm (exp.) | 16.0c | 255e |
| 5 | CsZn2BO3FCl (ref. 32) | R3 | [ZnO3F], [ZnO3Cl] | 3.5× KDP | >6.5 | — | — | — |
| 6 | Cs3Pb2(CH3COO)2Br3I2 (ref. 66) | Amm2 | [PbO2Br2I2] | 9× KDP | 2.70 | 0.27@1064 nm (calc.) | 6.0b | 39d |
| 7 | Pb2TiOF(SeO3)2Cl (ref. 67) | P21 | [PbO5Cl2F], [PbO6Cl], [TiO5F] | 9.6× KDP, 0.65× KTP | 3.34 | — | — | — |
| 8 | Pb2TiFO(SeO3)2Br (ref. 68) | P21 | [PbO5Br2F], [PbO6Br], [TiO5F] | 10× KDP | 3.26 | 0.19@1064 nm (calc.) | 10b | — |
| 9 | Pb2GaF2(SeO3)2Br (ref. 69) | P21 | [PbO5Br2F], [PbO6Br], [GaO3F3] | 4.5× KDP | 3.73 | — | — | — |
| 10 | Pb2GaF2(SeO3)2Cl (ref. 70) | P21 | [PbO5Cl2F], [PbO6Cl], [GaO3F3] | 4.5× KDP | 4.32 | — | 11b | 120d |
a
The SHG intensity was measured at 1064 nm when using KDP as the reference and at ∼2.1 μm when using KTP or AGS as the reference.
b
The IR cutoff edge was preliminarily measured on powder samples.
c
The IR cutoff edge was estimated on single crystals.
d
The LDT was preliminarily measured on powder samples.
e
The LDT was estimated on single crystals.