Na(CHN)[Zn(PO)(HPO)]: A Short-Wave Ultraviolet Open-Framework Zincophosphate Exhibiting Substantial Optical Dispersion Ability.

The exploration of short-wave ultraviolet (SUV; λ < 280 nm) transparent phosphates with substantial birefringence is crucial for the advancement of SUV laser industry. Despite their SUV transparency and potential for constructing materials with large birefringence, open-framework (OF) phosphates have rarely been explored for their birefringent properties. Herein, through a systematic exploration in this field, a new ethylenediamine-based OF zincophosphate, Na(CHN)[Zn(PO)(HPO)] (NEZPO), has been developed.

From K[ZnBPO] to K[(ZnAl)PO]: Substitution-Induced Microporous Zincoaluminophosphate with a Congruent-Melting Behavior.

An open-frame aluminophosphate, K[(ZnAl)PO] (KZAPO), was rationally designed by a substitution design strategy and synthesized by a high-temperature molten salt method. Compared with the parent crystal of K[ZnBPO], KZAPO was characterized by similar 4 × 8 × 8 networks, a comparable short-wave ultraviolet transparency and a more regular tetrahedral frame with the mixing of (ZnO) and (AlO) anionic groups, highlighting the multifunctional roles that anionic group mixing played in structural and property modulations. In particular, KZAPO was characterized by a high thermal stability (over 850 °C) and a congruent-melting behavior, being conducive to practical applications.

Molten Salt Synthesis of an Open-Frame Aluminum Phosphate BaAlPO with a Rare-Pyramidal AlO Group.

A new open-frame aluminophosphate, BaAlPO, was synthesized by a high-temperature flux method. BaAlPO features discrete [AlPO] chains with rare square-pyramidal AlO groups adopted. Especially, this pyramidal AlO group acts as an ideal "plane builder" or "vacancy inducer" to construct open-frame structures compared with an ordinary trigonal-bipyramidal AlO group.

Deep-Ultraviolet Nonlinear Optical Crystal Cs Al (B O ) O: A Benign Member of the Sr Be (BO ) O Family with [Al (B O ) O] Double Layers.

For the explorations of deep ultraviolet (DUV) nonlinear optical (NLO) borates, a type of important optoelectronic material, the (BO ) group has been long regarded as the sole microscopic optically-active unit, and toxic Be-containing raw materials are frequently-adopted. Herein, a new DUV NLO crystal, Cs Al (B O ) O (CABO), was designed and synthesized by simultaneously replacing the (BO ) groups and Be cations for (B O ) units and Al cations in Sr Be (BO ) O, which possesses a favorable structure, through a chemical co-substitution approach. CABO exhibits a considerable DUV NLO capability because of the wide band gap and large birefringence originating from the [Al (B O ) O] double layers.

BaZn(BO): A Nonlinear-Optical Material with Reinforced Interlayer Connections and Large Second-Harmonic-Generation Response.

A nonlinear-optical crystal BaZn(BO) (BZBO) is obtained that is constructed with [Zn(BO)O] units bridged by planar BO groups along the a axis based on the flexibility of the BO and ZnO groups. The distance between adjacent [Zn(BO)O] layers in BZBO is 5.07 Å, which is much shorter than those of KBeBOF, BaZn(BO), and NaCsBeB5O.