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1. An effective pathway to design and synthesize UV birefringent crystals via rational assembly of π-conjugated [CO ₃ ] ²⁻ and [NO ₃ ] ⁻ triangles

   https://doi.org/10.1039/d2tc05374h  

   Hu, Zhaowei; Liu, Lili; Zhang, Ruixin; Jing, Qun; Wang, Huan; Tian, Jindan; Xu, Jiayue; Halasyamani, P. Shiv (March 2023, Journal of Materials Chemistry C)

   Planar MO 3 (M = B, C, N) units have frequently been considered important structural components of novel birefringent crystal materials. An efficient approach for constructing new functional crystals is to simultaneously assemble multiple structural motifs together. Two compounds, Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O (X = Br and Cl), were synthesized by the integration of three kinds of anionic groups. More interestingly, the [CO 3 ] 2− and [NO 3 ] − groups in Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O are all coplanar with the aid of [NaO 7 ] 13− polyhedra, which can enhance the anisotropic polarizability. Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O have a large theoretical birefringence of ∼0.165 at 1064 nm and possess a short UV cut-off edge of ∼230 nm. Additionally, the two compounds exhibit good crystal growth habits. These properties illustrate that Na 3 Rb 6 (CO 3 ) 3 (NO 3 ) 2 X·6H 2 O are promising UV birefringent crystals. 

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2. Enhanced Silicon Photovoltaic Efficiency by Solar Light Spectral Modulation via Photonically Tuned Porphyrin–Iron Oxide Hybrid Thin Films

   https://doi.org/10.1002/ente.202300144  

   Lyu, Mengyao; Lin, Jou; Wang, Yuxin; Aulakh, Ovais; Ceja, Nathan; Ramesh, Mary Sheryl; Salazar, Elisabeth; Krupczak, John; Shi, Donglu (March 2023, Energy Technology)

   The temperature dependency of photovoltaic power conversion efficiency (PCE) has been a key challenge to solar applications due to intrinsic processes. Herein, an alternative strategy is developed by modulating the solar light spectrum with a series of photonic hybrids. Transparent thin films are synthesized with the solutions of porphyrin compounds and iron oxides which exhibit strong absorptions in the UV and IR regions. These spectral modulating thin films are photonically tuned via compositional optimization to absorb photons near 400 nm and above 1127 nm from solar spectrum to reduce thermalization and sub-bandgap absorption. These spectral modulators are applied in a particular configuration above a commercial silicon panel to partially filter the simulated solar light. The PCE of the silicon panel suffers a significant decrease due to temperature increase from 22.9 to 92.9 °C after 60 min solar irradiation, resulting in a PCE decrease from 25.1% to 16.3%. With the transparent spectral modulators, upon solar irradiation for 60 min, the maximum PCE has maintained at 20.5%. The mechanisms of PCE enhancement are identified based on reduced thermalization and sub-bandgap absorption. 

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3. New germanate and mixed cobalt germanate salt inclusion materials: [(Rb ₆ F)(Rb ₄ F)][Ge ₁₄ O ₃₂ ] and [(Rb ₆ F)(Rb _3.1 Co _0.9 F _0.96 )][Co _3.8 Ge _10.2 O ₃₀ F ₂ ]

   https://doi.org/10.1039/D0CE01099E  

   Carone, Darren; Usman, Mohammad; Klepov, Vladislav V.; Smith, Mark D.; Kocevski, Vancho; Besmann, Theodore M.; zur Loye, Hans-Conrad (December 2020, CrystEngComm)

   null (Ed.)

   Single crystals of two new germanates, [(Rb 6 F)(Rb 4 F)][Ge 14 O 32 ] and [(Rb 6 F)(Rb 3.1 Co 0.9 F 0.96 )][Co 3.8 Ge 10.2 O 30 F 2 ], were synthesized via high temperature RbCl/RbF flux growth. Both compounds crystallize in the cubic space group F 4̄3 m and possess the germanium framework of the previously reported salt inclusion material (SIM), [(Cs 6 F)(Cs 3 AgF)][Ge 14 O 32 ], related to the Ge 7 O 16 zeolitic family. These materials demonstrate the ability to accommodate a variety of salt-inclusions, and exhibit chemical flexibility enabling modifications of the framework through incorporation of Co. Alteration of the salt-inclusion led to intrinsic luminescence of [(Rb 6 F)(Rb 4 F)][Ge 14 O 32 ] while modification of the framework resulted in an unanticipated Rb/Co salt/inclusion in [(Rb 6 F)(Rb 3.1 Co 0.9 F 0.96 )][Co 3.8 Ge 10.2 O 30 F 2 ]. Fluorescence measurements were performed on [(Rb 6 F)(Rb 4 F)][Ge 14 O 32 ]. First-principles calculations in the form of density functional theory (DFT) were performed for [(Rb 6 F)(Rb 3.1 Co 0.9 F 0.96 )][Co 3.8 Ge 10.2 O 30 F 2 ] to elucidate its electronic and magnetic properties, and stability at 0 K. 

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4. Wide‐Bandgap R Ba ₃ (B ₃ O ₆ ) ₃ ( R = Nd, Sm, Tb, Dy, and Er) Single Crystals for Ultraviolet Nonlinear Optics

   https://doi.org/10.1002/adom.202401437  

   Sarker, Saugata; Wang, Yu; Benyacko, Caeli; Guan, Yingdong; Yoshida, Suguru; Yennawar, Hemant; He, Jingyang; Mao, Zhiqiang; Gopalan, Venkatraman (August 2024, Advanced Optical Materials)

   Abstract Discovery of new materials with enhanced optical properties in the visible and UV‐C range can impact applications in lasers, nonlinear optics, and quantum optics. Here, the optical floating zone growth of a family of rare earth borates,RBa₃(B₃O₆)₃(R= Nd, Sm, Tb, Dy, and Er), with promising linear and nonlinear optical (NLO) properties is reported. Although previously identified to be centrosymmetric, the X‐ray analysis combined with optical second harmonic generation (SHG) assigns the noncentrosymmetricPspace group to these crystals. Characterization of linear optical properties reveals a direct bandgap of ≈5.61–5.72 eV and strong photoluminescence in both the visible and mid‐IR regions. Anisotropic linear and nonlinear optical characterization reveals both Type‐I and Type‐II SHG phase matchability, with the highest effective phase‐matched SHG coefficient of 1.2 pm V⁻¹at 800‐nm fundamental wavelength (for DyBa₃(B₃O₆)₃), comparable to β‐BaB₂O₄(phase‐matchedd₂₂≈ 1.9 pm V⁻¹). Laser‐induced surface damage threshold for these environmentally stable crystals is 650–900 GW cm⁻², which is four to five times higher than that of β‐BaB₂O₄, thus providing an opportunity to pump with significantly higher power to generate about six to seven times stronger SHG light. Since the SHG arises from disorder on the Ba‐site, significantly larger SHG coefficients may be realized by “poling” the crystals to align the Ba displacements. These properties motivate further development of this crystal family for laser and wide bandgap NLO applications. 

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5. ND70 Series Basaltic Glass Reference Materials for Volatile Element ( H₂O , CO₂ , S, Cl, F) Measurement and the C Ionisation Efficiency Suppression Effect of Water in Silicate Glasses in SIMS

   https://doi.org/10.1111/ggr.12572  

   Moussallam, Yves; Towbin, William Henry; Plank, Terry; Bureau, Hélène; Khodja, Hicham; Guan, Yunbin; Ma, Chi; Baker, Michael B; Stolper, Edward M; Naab, Fabian U; et al (July 2024, Geostandards and Geoanalytical Research)

   We present a new set of reference materials, the ND70‐series, forin situmeasurement of volatile elements (H₂O, CO₂, S, Cl, F) in silicate glass of basaltic composition. The materials were synthesised in piston cylinders at pressures of 1 to 1.5 GPa under volatile‐undersaturated conditions. They span mass fractions from 0 to 6%m/mH₂O, from 0 to 1.6%m/mCO₂and from 0 to 1%m/mS, Cl and F. The materials were characterised by elastic recoil detection analysis for H₂O, by nuclear reaction analysis for CO₂, by elemental analyser for CO₂, by Fourier transform infrared spectroscopy for H₂O and CO₂, by secondary ion mass spectrometry for H₂O, CO₂, S, Cl and F, and by electron probe microanalysis for CO₂, S, Cl and major elements. Comparison between expected and measured volatile amounts across techniques and institutions is excellent. It was found however that SIMS measurements of CO₂mass fractions using either Cs⁺or O⁻primary beams are strongly affected by the glass H₂O content. Reference materials have been made available to users at ion probe facilities in the US, Europe and Japan. Remaining reference materials are preserved at the Smithsonian National Museum of Natural History where they are freely available on loan to any researcher. 

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