Dimensionality–Band Gap–Third-Harmonic Generation Property Relationship in Novel Main-Group Metal Iodates

Abstract

Three new main-group metal iodates, i.e., AgGa­(IO3)4, AgIn­(IO3)4, and Ag3In­(IO3)6, have been successfully synthesized by hydrothermal reactions at different temperatures. Single crystal X-ray diffraction analysis suggests that AgGa­(IO3)4 and AgIn­(IO3)4 exhibit unidimensional (1D) structures consisting of IO3 trigonal pyramids, MO6 (M = Ga and In) octahedra, and Ag+ counter cations. Ag3In­(IO3)6, however, exhibits a zero-dimensional (0D) structure composed of IO3 trigonal pyramids, InO6 octahedra, and Ag+ counter cations. The metal iodate compounds were further investigated by employing various characterization tools such as spectroscopic analysis, thermogravimetric analysis, density functional theory calculations, and local dipole moment calculations. In addition, the nonlinear optical (NLO) properties such as third-harmonic generation (THG) and two-photon absorption (2PA) of the reported iodates were assessed. The THG measurements on polycrystalline samples of the title compounds reveal that their third-order susceptibility (χ(3)) values are three to five times larger than that of α-SiO2. Based on the experimental 2PA coefficient (β) and laser-induced damage threshold of the metal iodates, it was demonstrated that the optical breakdown arises from NLO light–matter interaction. A comparison of the nonlinear figures of merit (χ(3)/β) for several related main-group iodates indicates that the 0D iodates are better than the 1D iodates and the In iodates are better than the Ga iodates. The results suggest a novel design principle for maximizing the NLO performance of this class of materials in terms of dimensionality, polarizability, and band gap.

Bi3(SeO3)3(Se2O5)F: A Polar Bismuth Selenite Fluoride with Polyhedra of Highly Distortive Lone Pair Cations and Strong Second-Harmonic Generation Response

“…The LIDT was estimated based upon the intensity in which the data points start to deviate from the dashed line in Figure . The LIDT of α-SiO 2 is ∼3.84 GW/cm 2 , which is consistent with our previous one measured at a slightly different wavelength (1500 nm) . The LIDT of Bi 3 (SeO 3 ) 3 (Se 2 O 5 )­F is ∼1.37 GW/cm 2 , which is about 2.8 times smaller than that of the reference.…”

“…The LIDT of Bi 3 (SeO 3 ) 3 (Se 2 O 5 )­F is ∼1.37 GW/cm 2 , which is about 2.8 times smaller than that of the reference. It is noteworthy that this value is higher than those for novel main-group metal iodates . Considering the pulse width of our laser (30 ps), multiphoton absorption is the essential mechanism for laser-induced damage for the sample .…”

Third Harmonic Upconversion and Self-Trapped Excitonic Emission in 1D Pyridinium Lead Iodide

“…14 The pump power where the THG response deviates from the cubic behavior determines the LIDT of the sample (Note 1 of the Supporting Information). 51 Materials with a high LIDT and THG efficiency are desired for potential applications. The LIDT for PyPbI 3 single crystals turns out to be ∼33 GW/cm 2 , which is nearly threefold larger than that of the benchmark 2D lead halides.…”

Chiral Ligand‐Driven Systematic Synthesis of Coordination Polymers with Non‐centrosymmetric Structures

“…A successful synthetic method to increase the possibility of NCS structures is introducing several NCS chromophores such as second‐order Jahn‐Teller (SOJT) distortive cations, highly polarizable d 10 metal cations, and π‐delocalized anionic groups [2] . Although it is true that the synthetic strategy has contributed significantly to the formation of NCS structures, the observed major products are still CS structures because the introduced asymmetric groups are easily aligned in an antiparallel manner [3] . Thus, it is an ongoing challenge to synthesize rationally designed solid‐state materials with macroscopic NCS structures systematically.…”

“…[2] Although it is true that the synthetic strategy has contributed significantly to the formation of NCS structures, the observed major products are still CS structures because the introduced asymmetric groups are easily aligned in an antiparallel manner. [3] Thus, it is an ongoing challenge to synthesize rationally designed solidstate materials with macroscopic NCS structures systematically. Quite a few novel hybrid materials with NCS structures have been successfully discovered by introducing a variety of chiral building blocks into the reaction media.…”