Fang Yuan-Bin, Fu Rui-Biao, Tang Hong-Xin, Shui Qi-Rui, Ma Zu-Ju, Wu Xin-Tao
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, Fujian, P. R. China.
University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Inorg Chem. 2021 Apr 19;60(8):5821-5828. doi: 10.1021/acs.inorgchem.1c00158. Epub 2021 Mar 29.
Nonlinear-optical (NLO) crystal is an important photoelectric functional material. In this work, a new NLO titanium iodate, (HO)Ti(IO), along with Ti(IO) has been synthesized under facile conditions. The space group of (HO)Ti(IO) is the chiral noncentrosymmetric group 3 (No. 146), with an interesting three-dimensional framework, while that of Ti(IO) is the centrosymmetric space group 1̅ (No. 2) containing one-dimensional chains. Thermogravimetric analysis shows that (HO)Ti(IO) and Ti(IO) have no weight loss below 220 and 390 °C, respectively. In addition, (HO)Ti(IO) not only is thermally stable up to 200 °C in an air atmosphere but also is stable in water. (HO)Ti(IO) has a moderate-intensity second-harmonic-generation (SHG) response (1.4×KDP), a large laser-induced damage threshold (46×AgGaS), and high transmittance in the wavelength ranges of 0.5-1.4 and 2.5-10 μm. Both local dipole moment and systematic theoretical calculations reveal that the SHG response of (HO)Ti(IO) is mainly because of the combined effect of [TiO] octahedra and IO and IO units. In a word, (HO)Ti(IO) exhibits good NLO performances, as well as water resistance and facile growth of a single crystal with high quality, indicating its potential application as NLO materials in the visible and mid-IR regions, especially the visible region.
非线性光学（NLO）晶体是一种重要的光电功能材料。在本工作中，一种新型的NLO碘酸钛（HO）Ti(IO)以及Ti(IO)在简便的条件下被合成出来。（HO）Ti(IO)的空间群是手性非中心对称群3（编号146），具有一个有趣的三维框架，而Ti(IO)的空间群是包含一维链的中心对称空间群1̅（编号2）。热重分析表明，（HO）Ti(IO)和Ti(IO)分别在220和390℃以下没有失重。此外，（HO）Ti(IO)不仅在空气气氛中在高达20℃时热稳定，而且在水中也稳定。（HO）Ti(IO)具有中等强度的二次谐波产生（SHG）响应（1.4×KDP）、较大的激光损伤阈值（46×AgGaS）以及在0.5 - 1.4和2.5 - 10μm波长范围内的高透过率。局部偶极矩和系统理论计算均表明，（HO）Ti(IO)的SHG响应主要是由于[TiO]八面体与IO和IO单元的综合作用。总之，（HO）Ti(IO)表现出良好的NLO性能，以及耐水性和高质量单晶的易生长性，表明其在可见光和中红外区域，特别是可见光区域作为NLO材料具有潜在应用。
