Variable dimensionality of the anion framework in four new borophosphates and fluoroborophosphates with short cutoff edges

Abstract

Two new borophosphates Cs3B3P4O16, Li(NH4)2B3P4O16, and two new fluoroborophosphates K4B2P2O9F2 and Rb3B2PO5F4 have been obtained via high-temperature solution method. Single-crystal X-ray diffraction indicates that all of them exhibit various anion...

Exploring Short-Wavelength Phase-Matching Nonlinear Optical Crystals by Employing KBe2BO3F2 as the Template

“…The infrared peak positions for K 2 B 4 SO 10 , Rb 2 B 4 SO 10 , and Cs 2 B 4 SO 10 do not differ much (Figure S4a). According to the literature studies, , the asymmetric and symmetric stretching vibrations (ν asym and ν sym ) of the [BO 3 ] units are observed at 1363–1375 and 944–950 cm –1 , respectively. The vibrational peaks of 803–813 and 582–584 cm –1 are caused by the out-of-plane bending [δ­(O–B–O)] of the [BO 3 ] groups.…”

“…The mixed-anionic compounds are attractive hunting grounds for probing NLO crystals due to their interesting physiochemical properties which are usually associated with their structural varieties. − Belonging to the mixed-anionic system, borosulfates and fluoroborophosphates are rich in crystal structures that are benefited from the interconnection of B–O groups with the [SO 4 ] or [PO 4 ] groups, respectively. − However, the small optical anisotropy of the rigid tetrahedra leads to non-phase-matching (NPM) properties that limit their application as novel NLO crystals in the short-wavelength UV area. , In the recent work from our group, an attempt was made to introduce planar π-conjugated [BO 3 ] groups into these systems to optimize their birefringence, and two cases of boron-rich borosulfate and fluoroborophosphate UV/deep-UV NLO crystals were successfully obtained. , Nevertheless, comprehensive research on the structure–properties relationships and a systematic exploration of these mixed-anionic borosulfates and fluoroborophosphates are still lacking. In this regard, by employing the KBBF structure as the template, we performed further research to explore promising unexampled UV/deep-UV NLO crystals in the borosulfate and fluoroborophosphate systems.…”

“…The infrared peak positions for K 2 B 4 SO 10 , Rb 2 B 4 SO 10 , and Cs 2 B 4 SO 10 do not differ much (Figure S4a). According to the literature studies, 45,47 S8). 52,53 In the principal planes, the effective nonlinearity (d eff ) expressions exist with three tensors d these four compounds are in the identical order of magnitude as the measured powder SHG effect (0.9−1.7 × KDP).…”

Hydroxyl-Driven Enhanced Birefringence in Borophosphates

“…To investigate the coordination geometry of anionic groups, the IR spectra of K 2 B 2 P 2 O 9 and (NH 4 ) 2 BP 2 O 7 (OH) are measured (Figure S7), they exhibit similar trend, aligning with the IR spectra commonly observed in other borophosphates. 30,53 The [PO 4 ] groups exhibit groups appear at 589−718 and 523−530 cm −1 , respectively. It is important to highlight that in the (NH 4 ) 2 BP 2 O 7 (OH) spectrum, certain peaks associated with hydroxyl groups are closely positioned to NH 4 + , which may pose a challenge in their differentiation (Table S8).…”

BaB2P2O8F2: A Fluoroborophosphate with [B2P2O8F2]∞ Layers and Deep-Ultraviolet Cutoff Edge

“…All of the peaks are also consistent with the previously reported works. 58,71,73,74 The UV−vis−near-IR (NIR) diffuse-reflectance spectrum of the samples is shown in Figure 2c, and it is clear that the cutoff edge of BaB 2 P 2 O 8 F 2 is below 200 nm, which indicates that BaB 2 P 2 O 8 F 2 can be used as a DUV optical material. The thermal properties were investigated by thermogravimetry and differential scanning calorimetry (TG−DSC) measurement (Figure 2d).…”