Alabarse Frederico G, Baptiste Benoît, Guarnelli Yoann, Joseph Boby, Haines Julien
Elettra Sincrotrone Trieste, Trieste 34149, Italy.
Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, (IMPMC), UMR 7590 CNRS-Sorbonne Université-IRD-MNHN, 4 place Jussieu, 75252 Paris, Cedex 5, France.
J Phys Chem C Nanomater Interfaces. 2023 Jul 18;127(29):14528-14533. doi: 10.1021/acs.jpcc.3c03513. eCollection 2023 Jul 27.
The porous aluminophosphate AlPO-17 with a hexagonal erionite structure, exhibiting very strong negative thermal expansion, anomalous compressibility, and pressure-induced amorphization, was studied at high pressure by single-crystal and powder X-ray diffraction in the penetrating pressure transmitting media N, O, and Ar. Under pressure, these guest species were confirmed to enter the pores of AlPO-17, thus completely modifying its behavior. Pressure-induced collapse in the plane of AlPO-17 no longer occurred, and this plane exhibited close to zero area compressibility. Pressure-induced amorphization was also suppressed as the elastic instability in the plane was removed. Crystal structure refinements at a pressure of 5.5 GPa indicate that up to 28 guest molecules are inserted per unit cell and that this insertion is responsible for the reduced compressibility observed at high pressure. A phase transition to a new hexagonal structure with cell doubling along the direction was observed above 4.4 GPa in fluid O.
具有六方菱沸石结构的多孔磷酸铝AlPO-17表现出非常强的负热膨胀、异常压缩性和压力诱导非晶化，在高压下通过在穿透压力传递介质N、O和Ar中的单晶和粉末X射线衍射对其进行了研究。在压力下，证实这些客体物种进入AlPO-17的孔中，从而完全改变了其行为。AlPO-17在 平面上由压力诱导的塌陷不再发生，并且该平面表现出接近零的面积压缩性。由于 平面中的弹性不稳定性被消除，压力诱导非晶化也受到抑制。在5.5 GPa压力下的晶体结构精修表明，每个晶胞中插入多达28个客体分子，并且这种插入是高压下观察到的压缩性降低的原因。在流体O中，在4.4 GPa以上观察到向沿 方向晶胞加倍的新六方结构的相变。
