K₂Na₃[{B₆O₁₀(OH)}{B₃O₄(OH)₃}] ⋅ H₂O: A Layered Borate Built by Mixed Oxoboron Clusters with Nonlinear‐Optical Property

Abstract

A new acentric borate, K2Na3[{B6O10(OH)}‐{B3O4(OH)3}] ⋅ H2O (1) has been made under solvothermal condition. 1 has layered structure made by B6O13(OH)‐based chains and B3O5(OH)3‐bridging clusters. Second‐harmonic generation (SHG) measurements reveal that 1 is a phase‐matchable nonlinear optical (NLO) material, showing the SHG signal intensity of 1.8 times that of KDP (KH2PO4). Besides, UV‐Vis diffuse reflectance spectrum shows that 1 has the short deep UV (DUV) absorption cutoff edge of 198 nm. Thermogravimetric analysis reveals it has good thermal stability. Also 1 represents firstly mixed oxoboron clusters‐made 2D layered borate with NLO property.

KCs2[GaB5O10](OH): A Zeolitic Galloborate Framework with a Nonlinear Optical Property

“…Besides, the lack of d-d and f-f electron transitions would result in a wide transparency in UV and deep-UV regions, greatly increasing the application ranges of NLO materials. Besides the typical β-BaB 2 O 4 (BBO), LiB 3 O 5 (LBO), and CsLiB 6 O 10 (CLBO), − a large number of NLO borates with short cutoff edges have been synthesized with inorganic cations in recent years, including LiBa 3 (OH)­[B 9 O 16 ]­[B­(OH) 4 ], K 2 Na 3 [{B 6 O 10 (OH)}­{B 3 O 4 (OH) 3 }]·H 2 O, and MgB 5 O 7 F 3 . − …”

Syntheses, structures and optical properties of two B3O7 cluster-based borates

“…Additionally, the high UV transparency of the B–O bond enables them to be applied in UV and even deep UV (DUV) regions. 11–13 From a structural point of view, boron shows flexible coordination geometries, namely the BO 3 triangle and BO 4 tetrahedron, which can connect via corner–/edge-sharing to form various oxoboron polyanionic clusters. 14–17 These diverse cluster units normally arrange in an orderly manner in the crystal lattice and interact with each other through covalent bonds or H-bonds to make up discrete clusters, 1D chains, 2D layers and 3D frameworks.…”

“…38,39 Additionally, the spherical coordination of alkali and alkaline earth metals can increase the possibility of acentric structures by reducing the symmetrical influences from centrosymmetric guest templates to acentric host frameworks. 11 Up to date, most of the UV/DUV NLO borates are alkali and alkaline earth metal borates, including the typical β-BaB 2 O 4 (BBO), LiB 3 O 5 (LBO) and CsLiB 6 O 10 (CLBO), 40–42 and the newly reported LiBa 3 (OH)[B 9 O 16 ][B(OH) 4 ], 2 Li 2 CsB 7 O 10 (OH) 4 (ref. 12) and MgB 5 O 7 F 3 .…”

CsB3O4(OH)2: a new deep-ultraviolet birefringent crystal with [B3O4(OH)2] anionic group

“…S3. † The absorption bands observed in the range of 1203-1535 cm −1 and 981 cm −1 can be ascribed to the stretching vibration of [BO 3 ] and [BO 4 ] groups, 30 respectively, while bands around 555-800 cm −1 are likely to stem from bending vibrations of the [BO 3 ] and [BO 4 ] groups, 24,39 respectively. In addition, the broad absorption peaks that appear at 3180-3480 cm −1 are indicative of the stretching vibrations of [OH] − groups.…”

“…According to previous research, the introduction of OH can eliminate the dangling bond of the terminal O atom, thereby increasing the band gaps. 6–8,21,23–26 It can also effectively increase the anisotropic polarization of [BO 3 ] units, leading to the delocation of π-electrons. For example, LiB 5 O 5 F 2 (OH) 4 , 6 Na[B 3 O 3 F 2 (OH) 2 ]·[B(OH) 3 ], 8 NH 4 B 11 O 16 (OH) 2 , 7 CaBO 3 H, 27 and NH 4 (B 6 PO 10 (OH) 4 )·H 2 O, 28 have been reported showing large birefringence.…”