Explorations of new second harmonic generation materials in Ag⁺-Hg²⁺/Bi³⁺-selenites systems afforded three new silver selenium oxides, namely, Ag₄Hg(SeO₃)₂(SeO₄) (1), Ag₂Bi₂(SeO₃)₃(SeO₄) (2) and Ag₅Bi(SeO₃)₄ (3). They exhibit flexible crystal chemistry. Compounds 1 and 2 are mixed valence selenium oxides containing Se(IV) and Se(VI) cations simultaneously. Compounds 1 and 3 exhibit a 3D open framework with 4-, 6- and 8-member polyhedral ring tunnels along a, b and c axes. Compound 1 crystallized in a polar space group and could display a subtle frequency doubling efficiency about 35% of the commercial KH₂PO₄ (KDP). UV-vis-NIR spectra reveal that compounds 1–3 are wide-band semiconductors with the optical bandgaps of 3.11, 3.65, 3.58 eV respectively. Theoretical calculations disclose that compounds 2 and 3 are indirect band gap structures and their bandgaps are determined by Ag, Bi, Se and O atoms together.

在Ag ⁺ -Hg ²⁺ / Bi ^3+-硒铁矿体系中探索新的二次谐波产生材料，得到了三种新的银硒氧化物，分别为Ag ₄ Hg（SeO ₃）₂（SeO ₄）（1），Ag ₂ Bi ₂（SeO ₃）₃（SeO ₄）（2）和Ag ₅ Bi（SeO ₃）₄（3）。它们表现出灵活的晶体化学性质。化合物1和2是同时含有Se（IV）和Se（VI）阳离子的混合价硒氧化物。化合物1和3表现出3D开放框架，沿着a，b和c轴具有4、6和8元多面体环隧道。化合物1在极性空间群中结晶，可以显示出微弱的倍频效率，约为商用KH ₂ PO ₄（KDP）的35％。UV-vis-NIR光谱表明，化合物1-3是宽带半导体，其光学带隙分别为3.11、3.65和3.58 eV。理论计算表明，化合物2和3为间接带隙结构，其带隙由Ag，Bi，Se和O原子共同确定。