A Facile Synthetic Route to a New SHG Material with Two Types of Parallel π‐Conjugated Planar Triangular Units

Abstract

A new SHG material, namely, Pb2(BO3)(NO3), which contains parallel π-conjugated nitrate and borate anions, was obtained through a facile hydrothermal reaction by using Pb(NO3)2 and Mg(BO2)2⋅H2O as starting materials. Its structure contains honeycomb [Pb2(BO3)]∞ layers with noncoordination [NO3](-) anions located at the interlayer space. Pb2(BO3)(NO3) shows a remarkable strong SHG response of approximately 9.0 times that of potassium dihydrogen phosphate (KDP) and the material is also phase-matchable. The large SHG coefficient of Pb2(BO3)(NO3) arises from the synergistic effect of the stereoactive lone pairs on Pb(2+) cations and parallel alignment of π-conjugated BO3 and NO3 units. Based on its unique properties, Pb2(BO3)(NO3) may have great potential as a high performance NLO material in photonic applications.

Na2Mg1−xZnxSiO4 (0 ≤ x ≤ 1): Noncentrosymmetric Sodium Metal Silicate Solid Solutions with Ultraviolet Nonlinear Optical Properties

“…Attributed to the nature's symmetry preference, major forms of naturally occurring and synthetically obtained crystalline materials are centrosymmetric. Thus far, however, several NCS chromophores that can facilitate macroscopic NCS space groups have been successfully proposed, which includes (1) two families of cations with second‐order Jahn–Teller distortions, namely, asymmetric lone pair cations and d 0 transition metal cations, (2) highly polarizable d 10 transition metal ions, and (3) anions in trigonal structures with π‐delocalized electrons such as nitrates, carbonates, and borates . Among them, a variety of interesting UV or deep‐UV NLO materials have been recently developed from π‐orbital anionic groups .…”

Structure and Properties of the Non‐Centrosymmetric Manganese(II) Borate Mn5(BO3)3OH

“…A large class of NCS compounds is constituted by borates, especially interesting as NLO materials with enhanced second harmonic generation (SHG) response, like for example β ‐BaB 2 O 4 (BBO), LiB 3 O 5 (LBO), Li 3 B 5 O 8 (OH) 2 , Pb 2 Ba 3 (BO 3 ) 3 Cl, Pb 2 (BO 3 )(NO 3 ), Se 2 (B 2 O 7 ), and Pb 2 BO 3 I . They offer the advantage of high UV transmittance and a high damage threshold, as well as chemical and mechanical stability, making them attractive for application as UV and deep‐UV lasers …”

Syntheses, Crystal Structures, and Properties of Two Quaternary Selenite/Tellurite‐Nitrates with Formula of Bi(SeO3)(NO3) and Bi3(μ3‐OH)(TeO3)3(NO3)2

“…Typically, CsPbCO 3 F has a large SHG response of ∼13.4×KDP, originating from enhancement via p‐π interaction between Pb 2+ and π‐conjugated [CO 3 ] 2– unit within the [Pb(CO 3 )] layers . Recently we have reported that a series of lead compounds containing two types of π‐conjugated planar triangular units, for example, Pb 2 (BO 3 )(NO 3 ) exhibits response of ∼9.0 times that of KDP, which is attributed to the presence of multiple SCALP cation and π‐conjugated unit, improving the SHG response. Geng et al reported one new lead‐selenite‐nitrate, namely, Pb 2 (SeO 3 )(NO 3 ) 2 , has a SHG response approximately 2.0×KDP .…”