Non-centrosymmetric chalcogenides are attracting considerable attention as highly promising infrared nonlinear optical (IR-NLO) candidates, but it is challenging to simultaneously achieve sufficient second-harmonic-generation coefficient (deff > 0.5 × AgGaS2) and large energy gap (Eg > 3.5 eV). In this work, a novel ternary chalcogenide, Cs5Ga9S16 with an ultra-wide Eg of 4.05 eV, has been successfully obtained. This sulfide belongs to the monoclinic space group Pn (No. 7) with a novel 3D anionic [Ga9S16]5– framework that is formed by super-polyhedral [Ga9S23] units through corner-sharing S atoms. Such a unique crystal structure displays desirable characteristics which indicate a promising IR-NLO candidate: favourable phase-matching feature, sufficient deff (0.7 × AgGaS2), ultrahigh laser-induced damage threshold (31.6 × AgGaS2) and broad transparent region (0.27−14.96 µm). In addition, systematic theoretical studies and structural analysis suggest that the desirable IR-NLO performances can be attributed to the super-polyhedral building blocks. This finding may provide useful insight into the understanding and designing other high-performance IR-NLO candidates with super-polyhedral-built structures.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |